Re: Profiling the memory in D
On Wednesday, 4 December 2019 at 22:51:45 UTC, Steven
Schveighoffer wrote:
I localized that the leak was actually being caused by
websockets. I want to write down my experience because I did some
weird stuff which seems to be working but I want to learn how it
actually make sense and works.
I had a fancy work flow which caused by that bug
https://github.com/vibe-d/vibe.d/issues/2169 which disallowed to
open multiple sockets from my main process.
I solved that by lunching multiple process and using one web
socket by one process. And communicated this process and my main
process via zmqd.
My suggestion is; don't do that. Don't be super creative with
current Vibe websockets. I had this unidentifable leak which took
to much time to localize.
The bug I created around one year ago is solved now so I left
creating processes approach and put web sockets in to a list.
Next problem I had while listening 300 websocket was I got some
crushes within
webSocket.dataAvailableForRead() function, I am not sure if it is
a bug or my misusage some how so I haven't created a bug yet. But
my question to vibe forum can be seen
https://forum.rejectedsoftware.com/groups/rejectedsoftware.vibed/thread/112309/
I solved that ( I hope ) by using something like:
if ( webSocket.waitForData(0.msecs) &&
webSocket.dataAvailableForRead() )
I know it looks so wierd to wait for 0.msecs but things seems to
be working :/ .
The last problem I had was with closing the socket because this
sockets are getting disconnected time to time. I need to close
and reopen. When I call
webSocket.close() directly, after my program runs about 1 day it
was freezing in a function called epoll while calling
webSocket.close().
I also find another weird solution to that problem :
while ( true )
{
auto future = vibe.core.concurrency.async( {
socket.socket.close(); return true;} );
vibe.core.core.sleep(100.msecs);
if ( future.ready() )
break;
writeln( " Couldn't close the socket retring ");
}
sockets.remove(uniqStreamName);// BTW order of this removal
matters if you remove
//from your list before closing the ticket you are screwed.
Which seems to be working with 300 websockets around 2 days
without any leak nor crush neither freeze.
As I pointed in the beginning I don't have any question or
problems now but I am very open to feedback if you guys have any.
Erdemdem
Re: const and immutable values, D vs C++?
On Wednesday, 4 December 2019 at 14:44:43 UTC, Ola Fosheim
Grøstad wrote:
When is there a noticable difference when using const values
instead of immutable values in a function body? And when should
immutable be used instead of const?
f(){
const x = g();
immutable y = g();
... do stuff with x and y …
}
I'm comparing D to C++ and I get the following mapping:
D:
enum constant = number
C++:
enum : decltype(number) { constant = number }
D:
auto p = g()
C++:
auto p = g()
D:
const p = g()
C++:
const auto p = g()
D:
immutable p = g()
C++:
hmmm...
Has anyone done a feature by feature comparison with C++? It
would be interesting to see what it looks like.
Unfortunately I am not yet good with D to answer your question .
But Ali Çehreli made some comparesions with C++.
https://dconf.org/2013/talks/cehreli.pdf
And I think you will find the answers of your questions in it
also.
Re: Profiling the memory in D
On Wednesday, 4 December 2019 at 15:38:36 UTC, Steven Schveighoffer wrote: On 12/4/19 3:10 AM, Erdem wrote: I am used to have cool tools like valgrid massif to visualize the memory usage from C++ but in D it seems I am blind folded looking for the problem. Until now I tried: --vgc option which show million things which makes it not useful --build=profile-gc which seems to slow down my program like *200 times and I have some operation depending on time which makes creating the real case of the application impossible. The observation itself effect the experiment very badly. Since this options are not useful for me, I tried to put debug logs in critical places to estimate where I am losing memory. I couldn't find a D native call to get the memory usage of the program. I had to call a shell command which also slows down the app. This slow down causes me to not be able to put this debug log too many places or in critical loops. I manage to narrow it down a bit. Than I wanted to check the object instances to find out which objects are getting bigger. I tried GC.sizeOf(&object) which always prints 0. GC.sizeOf also does not works with associative arrays , I don't see any usefull case than GC.sizeOf(array.ptr). That is the background of my questions and my questions are: Is there a better way to visualize the memory in D something like valgrid massif? profile-gc literally makes to program not do anything due to slow down is there any way to profile-gc in a faster fashion? Is there a native function which will return the memory usage of my program? If it's total GC memory only you are interested in, then try the D runtime switch for the GC: --DRT-gcopt=profile:1 This will print out a summary of GC usage at the end of your program, and shouldn't significantly affect runtime. Is there a function to return sizes of AAs and even class instances ? Class instances have a compiler-defined size. Try __traits(classInstanceSize, SomeClass) This is the compile-time size of that specific type. If you have a class instance, and you want the actual class size, in the case of a derived instance, you may retrieve that using typeid(classInstance).initializer.length. Note also that this is not necessarily the size consumed from the GC! If you want *that* size, you need to use GC.sizeof(cast(void*)object) (you were almost correct, what you did was get the GC size of the *class reference* which is really a pointer, and really lives on the stack, hence the 0). -Steve GC.sizeof(cast(void*)object) will be super useful. I will use that. I also tried GC: --DRT-gcopt=profile:1 already. It provides so little information. I need to find out which member AA or array of which object is causing this memory problem of mine.I am ending up around 2GB of ram usage in a single day. Is there any way to manipulate profile-gc flag on run time? Like I will start my program without it somehow and after the my program initializes I will turn it on. One last thing in my program I am getting a message from vibe sometimes like "leaking eventcore driver because there are still active handles". I use websockets and do web requests. I wanted to add that because I saw you fixed something with Redis about that in https://github.com/vibe-d/vibe.d/issues/2245. Thanks for your help and replies Steve.
Referance usage in async function
I have simplified my problem which can be seen below.
import std.stdio;
import vibe.core.core;
import vibe.core.concurrency;
import vibe.data.json;
void main()
{
int[] list;
bool ListManipulator(ref int[] list)
{
list ~= 2;
list ~= 4;
return true;
}
bool ListManipulatorPointer( int[]* list)
{
*list ~= 2;
*list ~= 4;
return true;
}
auto future = vibe.core.concurrency.async(&ListManipulator,
list);
future.getResult();
writeln(list); > prints empty list
future = vibe.core.concurrency.async(&ListManipulatorPointer,
&list);
future.getResult();
writeln(list); > prints [2,4]
}
Why passing the pointer works meanwhile passing as reference does
nothing? I feel that is more D issue than vibe.d which I can
learn something I hope.
Erdem
Re: What is the replacement for deprecated array removal
On Monday, 18 November 2019 at 21:14:53 UTC, Steven Schveighoffer wrote: On 11/18/19 3:53 PM, kerdemdemir wrote: Is there any way to remove list of elements efficiently with a dynamical array? It seems kind of silly that it's not allowed, but maybe it will be possible after the deprecation is removed. But you could do something like this: list = list.remove!(a => removeList.canFind(a)); This is going to suck. Because it's O(n^2). Should be O(n + m) way to do it (assuming you have a sorted index list). Or is there anyway converting a dynamical array into a form which is like a AliasSeq? An AliasSeq is a compile-time construct, and cannot be created from a runtime array. -Steve Thanks for awesome answers man , Yes that sucks real hard because unlike that dummy example in my real case == compression will be too expensive I can't simply use canFind on every index. I guess I need to recreate a new dynamical array each time which is also horrible. It is a bit weird that such a general case like removing list of elements does not work. And I really do not know the real use of [0,1,2,3].remove(1,2,3). I mean in unit test it looks cool but in real life you will have dynamically calculated indexes. Erdem
Re: What is the replacement for deprecated array removal
On Monday, 18 November 2019 at 20:48:40 UTC, kerdemdemir wrote: On Monday, 18 November 2019 at 20:37:50 UTC, Steven Schveighoffer wrote: If I follow the code correctly, it's treating your array as a tuple of pos/len to remove. So it looks like your code is equivalent to remove(tuple(0, 2)); Which is probably not what you want. This probably explains why it's being deprecated, it's too confusing to the compiler. And looking at git blame goes back to this PR: https://github.com/dlang/phobos/pull/6154 -Steve Sorry to be horrible at explaining but remove(tuple(0, 2)); is not what I want. I have an array which goes from 0 to 5. And I want to remove odd numbers. remove(tuple(0, 2)); defines a starting index and a ending index but I need to delete not consecutive elements. In the case of odd number from 0 to 5 that will be 1, 3 and 5 . It is so weird when you type it is allowed like remove(1, 3, 5) but unexpectedly remove([1,3,5]) does not work the same way. I think if I can convert [1,3,5] to a AliasSeq that could be ok also. Erdem I read your message again now and I see that you weren't suggesting remove(tuple(0, 2)) but you were pointing out it is not what I want as well. Is there any way to remove list of elements efficiently with a dynamical array? Or is there anyway converting a dynamical array into a form which is like a AliasSeq? Erdem
Re: What is the replacement for deprecated array removal
On Monday, 18 November 2019 at 20:37:50 UTC, Steven Schveighoffer wrote: If I follow the code correctly, it's treating your array as a tuple of pos/len to remove. So it looks like your code is equivalent to remove(tuple(0, 2)); Which is probably not what you want. This probably explains why it's being deprecated, it's too confusing to the compiler. And looking at git blame goes back to this PR: https://github.com/dlang/phobos/pull/6154 -Steve Sorry to be horrible at explaining but remove(tuple(0, 2)); is not what I want. I have an array which goes from 0 to 5. And I want to remove odd numbers. remove(tuple(0, 2)); defines a starting index and a ending index but I need to delete not consecutive elements. In the case of odd number from 0 to 5 that will be 1, 3 and 5 . It is so weird when you type it is allowed like remove(1, 3, 5) but unexpectedly remove([1,3,5]) does not work the same way. I think if I can convert [1,3,5] to a AliasSeq that could be ok also. Erdem
Re: What is the replacement for deprecated array removal
int[] removeList;
for ( int i = 0; i < tempMap[0].length; i++ )
{
if ( i%2 == 0 )
removeList ~=i;
}
writeln(removeList); (prints 0,2,4)
tempMap[1].remove(0,2,4);
tempMap[2].remove(removeList);
tempMap[3].remove(tuple(0,1),tuple(2,3),tuple(4,5) );
Even weirder(at least for me)
int[] removeList is [0,2,4]
And .remove returns different results for .remove(0,2,4); and
.remove(removeList)
Is there anyway to convert int[] to a sequence like 0,2,4
Erdem
What is the replacement for deprecated array removal
I know my example can be shortened but please excuse me that I am
pasting directly
import std.stdio;
import std.math;
import std.range;
import std.algorithm;
import std.typecons;
int[][4] tempMap;
void main()
{
int[] temp = [ 1, 2, 3 , 4 ,5 ];
tempMap[0] = temp.dup;
tempMap[1] = temp.dup;
tempMap[2] = temp.dup;
tempMap[3] = temp.dup;
int[] removeList;
for ( int i = 0; i < tempMap.length; i++ )
{
if ( i%2)
removeList ~=i;
}
tempMap[1].remove(removeList);
writeln(tempMap);
}
Results with that warning:
onlineapp.d(24): Deprecation: function
std.algorithm.mutation.remove!(cast(SwapStrategy)2, int[],
int[]).remove is deprecated
How can I remove a list of indexes with remove ?
Erdem
ggplotd Fixed ratio between x and y axes
How can I configure a fixed ratio between x and y axes in ggplotd ? I easily found what I am looking for in ggplot which ggplotd inspires a lot. http://www.cookbook-r.com/Graphs/Axes_(ggplot2)/ But ggplotd documentation does not have any info about that. Even I go through the source code spend around half a hour I couldn't figure out how to achieve: sp <- ggplot(dat, aes(xval, yval)) + geom_point() sp + coord_fixed(ratio=1/3) Erdem
Re: Applying a function each respective 2 elements of an array
On Sunday, 10 March 2019 at 09:43:59 UTC, Dennis wrote: On Sunday, 10 March 2019 at 08:59:59 UTC, kerdemdemir wrote: Can I avoid for loops and solve my problem with std algorithms or ranges ? Try slide: https://dlang.org/phobos/std_range.html#slide And then use map. I think that will work that is exactly what I am looking for thanks Erdem
Applying a function each respective 2 elements of an array
I have an array like(In my real problem my data structs is more
complex ) :
auto a = [2,3,4,5,6,7];
I want to apply a operation in a fashion like :
[ 2 , 3 ] --> apply foo and get return result -1
[ 3 , 4 ] ---> -1
[ 4 , 5 ] ---> -1
and so on...
operation might be :
int foo ( int a, int b)
{
return a - b;
}
So my expected result is [-1,-1,-1,-1,-1]
I tried fold but fold add up the result of the last operation.
Range utilities like "chunks" does not help because "chunks"
transforms the array into a range like [2,3],[4,5],[6,7].
Can I avoid for loops and solve my problem with std algorithms or
ranges ?
Removing the precision from double
I have two numbers
First The price = 0.0016123
Second Maximum allowed precision = 0.0001(it can be only
0.001, 0.0001, 0.1, ..., 0.01 bunch of zeros and than
a one that is it)
Anything more precise than the allow precision should truncated.
So in this case 0.0016123 should turn into 0.0016.
I coded this which in my tests have no problem :
double NormalizeThePrice( double price, double tickSize)
{
import std.math : floor;
double inverseTickSize = 1.0/tickSize;
return floor(price * inverseTickSize) * tickSize;
}
writeln(NormalizeThePrice(0.0016123, 0.0001));
Returns 1.6e-07 as excepted.
I am doing trading and super scared of suprices like mathematical
errors during the multiplications(or division 1/tickSize) since
market will reject my orders even if there is a small mistake.
Is this safe? Or is there a better way of doing that ?
Erdemdem
Re: Is there websocket client implementation for D
Hi
vibe.d has a client implementation.
http://vibed.org/api/vibe.http.websockets/WebSocket
It is as simple as :
auto ws_url =
URL("wss://stream.binance.com:9443/ws/ethbtc@aggTrade");
auto ws = connectWebSocket(ws_url);
if ( !ws.connected )
return;
while ( true )
{
if (ws && ws.dataAvailableForRead())
{
writeln("Recieve", ws.receiveText());
}
sleep(100.msecs);
}
Connecting two web sockets at the same time with vibe.d
I am blocked in my project because of an issue while using
websockets.
I can simplify my problem like :
auto ws_url =
URL("wss://stream.binance.com:9443/ws/ethbtc@aggTrade");
auto ws = connectWebSocket(ws_url);
if ( !ws.connected )
return;
sleep(2.seconds);
ws_url = URL("wss://stream.binance.com:9443/ws/iotabtc@depth");
auto ws2 = connectWebSocket(ws_url);
if ( !ws2.connected )
return;
If I don't close the first socket before opening the second one I
am getting two different exceptions which can be seen in my
question which I already ask in vibe.d's forum :
https://forum.rejectedsoftware.com/groups/rejectedsoftware.vibed/thread/52273/
Since I am blocked I am open to any suggestions. Or if some one
knows an alternative socket implementation I may have to switch
to another library.
So do you guys have any suggestions or an alternative library for
socket handling?
Erdem
Finding the last executed line by checking dmd core
After a big refactor my code crushes I have no idea where. I am only getting : Program exited with code -11 And a core file. I used to use gdb for c++ coredumps. With what program&option I can check dmd core file? Erdemdem
Re: How to customize vibe.data.json
On Friday, 30 March 2018 at 17:58:23 UTC, Seb wrote:
On Friday, 30 March 2018 at 16:47:52 UTC, kerdemdemir wrote:
Hi,
In vibe's web
page(http://vibed.org/api/vibe.data.json/serializeToJson) it
is told that I should implement
[...]
I think you are looking for this -
https://github.com/vibe-d/vibe.d/pull/2088
Feel free to ping the people there ;-)
struct RESTTime {
SysTime time;
alias time this;
static RESTTime fromString(string v) { return
RESTTime(SysTime.fromSimpleString(v)); }
string toString() const { return time.toSimpleString(); }
}
struct TradeData
{
UUID sellOrderID;
UUID buyOrderID;
SysTime buyOrderTime;
SysTime sellOrderTime;
}
void main() {
TradeData t;
Json jsonResult = t.serializeToJson();
writeln(jsonResult.toString());
}
Unfortunately what is shown in the forum is not working with
SysTime.
My program is being terminated in
std.datetime.SysTime.toISOExtString() function by code -11.
I hope it does not sound like spoon feeding but do you know any
solution for SysTime. I am working on it in parallel.
Erdem
Re: How to customize vibe.data.json
On Friday, 30 March 2018 at 17:58:23 UTC, Seb wrote: On Friday, 30 March 2018 at 16:47:52 UTC, kerdemdemir wrote: Hi, In vibe's web page(http://vibed.org/api/vibe.data.json/serializeToJson) it is told that I should implement [...] I think you are looking for this - https://github.com/vibe-d/vibe.d/pull/2088 Feel free to ping the people there ;-) Exactly :)
How to customize vibe.data.json
Hi,
In vibe's web
page(http://vibed.org/api/vibe.data.json/serializeToJson) it is
told that I should implement
Json toJson() const;
static T fromJson(Json src);
string toString() const;
static T fromString(string src);
I think I should implement those as member functions(I am not
sure).
I have a struct like:
struct TradeData
{
import std.uuid : UUID;
import std.datetime : SysTime;
UUID sellOrderID;
UUID buyOrderID;
SysTime buyOrderTime;
SysTime sellOrderTime;
}
What I want is automatically json conversion of UUID and SysTime
classes by returning UUID.toString() and SysTime.toSimpleString()
methods when serializeToJson() is being called. Since these are
std classes I don't know how can I manipulate them.
Can you please tell me how should I use toJson(), fromJson()
functions for customizing user defined objects.
Erdem
Making mir.random.ndvariable.multivariateNormalVar create bigger data sets than 2
I need a classifier in my project. Since it is I believe most easy to implement I am trying to implement logistic regression. I am trying to do the same as the python example: https://beckernick.github.io/logistic-regression-from-scratch/ I need to data sets with which I will test. This works(https://run.dlang.io/is/yGa4a0) : double[2] x1; Random* gen = threadLocalPtr!Random; auto mu = [0.0, 0.0].sliced; auto sigma = [1.0, 0.75, 0.75, 1].sliced(2,2); auto rv = multivariateNormalVar(mu, sigma); rv(gen, x1[]); writeln(x1); But when I increase my data set size from double[2] to double[100] I am getting an assert : mir-random-0.4.3/mir-random/source/mir/random/ndvariable.d(378): Assertion failure which is: assert(result.length == n); How can I have a result vector which has size like 5000 something? Erdemdem
opCmp with double values
In documentation and forums I found some example for overloading
opCmp for int values. But I couldn't see any examples for double
values.
That is what I come up with my own:
struct AdjustableVal ( T = double )
{
this ( T initVal )
{
curVal = initVal;
initialVal = initVal;
}
int opCmp( T rhs ) const {
auto diff = curVal - rhs;
if ( fabs(diff) < 0.0001 )
return 0;
else if ( diff < 0 )
return -1;
else
return 1;
}
T curVal;
T initialVal;
}
Do you guys see any problem with it or any suggestions?
Secondly if the value type(T) does not have "-" operator, is it
possible to still get my code compiled somehow with static_if?
Erdem
Re: Finding equivalent of C++ feature in D documentation.
On Saturday, 23 December 2017 at 15:58:27 UTC, Seb wrote: On Saturday, 23 December 2017 at 15:45:33 UTC, Mike Franklin wrote: On Saturday, 23 December 2017 at 15:04:30 UTC, kerdemdemir wrote: Is there any better way for me to search C/C++ equivalent features? As a humble suggestion would it make sense to make a table with feature names and corresponding name of the same feature in other languages ? Try this: https://wiki.dlang.org/Programming_in_D_for_C%2B%2B_Programmers ... and potentially this: https://wiki.dlang.org/Coming_From Those resources are community maintained. When I was first learning D, if I encountered a problem and struggled to a solution, I would make an attempt to documented it on the D wiki to try and save others from having to go through the same difficulty. I encourage you to do the same. Mike There are these two pages: https://dlang.org/ctod.html https://dlang.org/cpptod.html Thanks guys both pages are good. @Mike I really want to add this case about M.I.L syntax in to wiki page. But since I am not a D pro; I am shy and also I am not sure if I have the permission to modify this page. Do you suggest me to try adding this spesific to the wiki page?
Finding equivalent of C++ feature in D documentation.
I needed to find equivalent of member initialization list in D. After searching ~10 minutes I found D has very elegant solution (https://dlang.org/spec/class.html#field-init) after reading through whole constructor page. My question is not technical this time I have my solution. But I think when I google "Member inilization in D" I am expecting to be directed to correct documentation. This unfortunately happens a lot to me. And this minutes sum into hours and inefficiency. Is there any better way for me to search C/C++ equivalent features? As a humble suggestion would it make sense to make a table with feature names and corresponding name of the same feature in other languages ? Erdem
Re: One liner for creating an array filled by a factory method
On Friday, 22 December 2017 at 23:33:55 UTC, Mengu wrote:
On Thursday, 21 December 2017 at 21:11:58 UTC, Steven
Schveighoffer wrote:
On 12/21/17 4:00 PM, kerdemdemir wrote:
I have a case like :
http://rextester.com/NFS28102
I have a factory method, I am creating some instances given
some enums.
My question is about :
void PushIntoVector( BaseEnum[] baseEnumList )
{
Base[] baseList;
foreach ( tempEnum; baseEnumList )
{
baseList ~= Factory(tempEnum);
}
}
I don't want to use "foreach" loop. Is there any cool std
function that I can call ?
Something like baseEnumList.CoolStdFunc!( a=> Factory(a)
)(baseList);
https://dlang.org/phobos/std_algorithm_iteration.html#map
-Steve
so basically it becomes:
Base[] baseList = baseEnumList.map!(el => Factory(el));
there's also a parallel version of map [0] if you ever need to
map the list concurrently.
[0] https://dlang.org/phobos/std_parallelism.html#.TaskPool.map
Yeah that was very easy and I used to use map for this purposed a
lot already. I don't know why I get confused. Thanks guys for
correction. I began to think like map could transform but it
can't create vector of elements and this confused me.
Converting member variables to strings with using reflection from base class
I want to make a logging function for member variables by using
reflection.
import std.stdio;
class D : B
{
override void foo() {
a = 4.0;
b = 3.0;
}
double a;
double b;
}
class B
{
void Log()
{
auto a = [__traits(derivedMembers, D)];
foreach(memberName; a) {
// Somehow write only member variables with their
names
// Result should be : a = 4.0, b = 3.0
}
}
void foo()
{
}
}
void main()
{
auto b = new D;
b.Log();
}
As I wrote in the comments I want to see member variable's name
and its value.
What is the best way to achieve that?
Erdem
One liner for creating an array filled by a factory method
I have a case like :
http://rextester.com/NFS28102
I have a factory method, I am creating some instances given some
enums.
My question is about :
void PushIntoVector( BaseEnum[] baseEnumList )
{
Base[] baseList;
foreach ( tempEnum; baseEnumList )
{
baseList ~= Factory(tempEnum);
}
}
I don't want to use "foreach" loop. Is there any cool std
function that I can call ?
Something like baseEnumList.CoolStdFunc!( a=> Factory(a)
)(baseList);
Erdem
Re: Passing anonymous enums as function parameters
enum
{
a = "foo",
b = "bar",
c = "baz";
}
is identical to
enum a = "foo";
enum b = "bar";
enum c = "baz";
Thanks Jonathan I think that changes my point of perspective.
And Jacob Carlborg I like the third option a lot with aliases
good to know that
enum Foo : string
{
KErdem
Ali
Zafer
Salih
//etc...
}
alias KErdem = Foo.KErdem
alias Ali = Foo.Ali
// etc...
Erdem
Re: Passing anonymous enums as function parameters
What I meant with anonymous enums was:
https://dlang.org/spec/enum.html#anonymous_enums. Maybe I
couldn't explain well but I believe D have anonymous enums. I am
sorry I have forgotten to remove " :string" in my example from
the "enum : string". Please stretch out ": string" part my
problem is not related with that.
I am not sure if it is a good one but I found a solution for my
problem
double ReturnCoolNess(U)( U enumVal )
{
switch (enumVal)
{
case KErdem:
{
return 0.0
}
case Ali:
{
return 100.0;
}
case Salih:
{
return 100.0;
}
// etc..
}
}
ReturnCoolNess(KErdem); ---> Compiles
D does not have anonymous enums. Either you're declaring an
enum which creates a new type and therefore has a name and a
base type, or you're just creating manifest constants that
don't create a new type. e.g.
enum MyEnum : string
{
a = "hello",
b = "foo",
c = "dog",
d = "cat"
}
vs
enum string a = "hello";
enum string b = "foo";
enum string c = "dog";
enum string d = "cat";
or
enum a = "hello";
enum b = "foo";
enum c = "dog";
enum d = "cat";
If you want a function to accept values that aren't tied to a
specific enum, then just have the function take the base type.
Now, within sections of code, you can use the with statement to
reduce how often you have to use the enum type's name, e.g.
with(MyEnum) switch(enumVal)
{
case a: { .. }
case b: { .. }
case c: { .. }
case d: { .. }
}
but you can't have an enum without a name or just choose not to
use an enum's name. With how enums work in D, there's really no
point in having them if you're not going to treat them as their
own type or refer to them via the enum type's name. If that's
what you want to do, then just create a bunch of manifest
constants.
- Jonathan M Davis
Passing anonymous enums as function parameters
I have an enum statement :
enum : string
{
KErdem
Ali
Zafer
Salih
//etc...
}
I don't want to give a name to my enum class since I am accessing
this variables very often.
But I also have a function like:
double ReturnCoolNess( /* Is there any way? */ enumVal )
{
switch (enumVal)
{
case KErdem:
{
return 0.0
}
case Ali:
{
return 100.0;
}
case Salih:
{
return 100.0;
}
// etc..
}
}
Is there any way I still keep my enum anonymous and be able to
call functions with different enumarations. Or is there any other
way to call named enums without type name ?
Re: Scope failure is not preventing application crush in case of uncaught exceptions
On Saturday, 16 December 2017 at 20:56:26 UTC, ketmar wrote: kerdemdemir wrote: As far as I know scope(failure) should be collecting all failure cases. nope. `failure` scope won't stop exception propagation, it is just called before exception leaves your function, to give you a last chance to do some immediate cleanup. Than do I still need to catch'em all? For me it doesn't matter the which exception it is. It is more important for me to not pollute my code with so many exception related lines. What is the most compact way for me to catch'em all?
Scope failure is not preventing application crush in case of uncaught exceptions
While calling this function :
bool PublicMarketCall( ref Json result )
{
string fullUrl =
"https://bittrex.com/api/v1.1/public/getmarketsummaries";;
Json data;
try
{
requestHTTP(fullUrl,
(scope req) {
req.method = HTTPMethod.GET;
},
(scope res) {
data = parseJsonString(res.bodyReader.readAllUTF8());
}
);
}
catch ( std.json.JSONException e )
{
writeln("Exception was caught while making the public call: ",
fullUrl);
return false;
}
scope(failure)
writeln("Exception was caught while public data: ", fullUrl);
return false;
}
Very rarely (I am calling this function thousands of times in a
day) like once in a day I am getting a crush while calling
requestHTTP function :
object.Exception@../../../.dub/packages/vibe-d-0.8.1/vibe-d/core/vibe/core/drivers/libevent2.d(375):
Failed to connect to host 104.17.154.108:443: 7FF703F4F617
??:? [0x606cee]
??:? [0x60ceb2]
exception.d:421 [0x4644a3]
exception.d:388 [0x41396d]
libevent2.d:375 [0x59002b]
net.d:129 [0x5be726]
client.d:610 [0x4a8ed4]
client.d:528 [0x4a7224]
client.d:462 [0x4a5a3f]
client.d:157 [0x4a5819]
client.d:133 [0x4a52bf]
--> Some files belonging my function
app.d:41 [0x43b947]
??:? [0x612f3e]
??:? [0x612efd]
??:? [0x612df8]
__entrypoint.d:8 [0x43be54]
??:? __libc_start_main [0x3de282f]
??:? [0x406fb8]
Program exited with code 1
As far as I know scope(failure) should be collecting all failure
cases. And my application shouldn't crush with uncaught
exceptions. What I am missing?
Problem with digest Hmac sha256 method and another problem while using openssl hmac
Hi,
I need to have the same result while using :
openssl dgst -sha256 -hmac "somestring"
But the server rejecting my generated hmac with the code below .
auto hmac = HMAC!SHA256("somestring".representation);
hmac.put(url.representation);
auto generatedHmac = hmac.finish();
string generatedHmacStr =
std.digest.digest.toHexString(generatedHmac);
Saying generatedHmac is not correct.
Than I wanted to give a try with deimos-openssl like:
ubyte[32] hmac_sha256( string key, string data) {
HMAC_CTX *ctx = new HMAC_CTX;
HMAC_CTX_init(ctx);
auto digest = HMAC(EVP_sha256(),
cast(void *) key,
cast(int) key.length,
cast(ubyte*) data,
cast(int) data.length,
null,null);
ubyte[32] array = digest[0..32];
return array;
}
But I am getting a linking error :
undefined reference to
`_D6deimos7openssl3evp13env_md_ctx_st6__initZ'
My dependencies in dub.json file is like:
"dependencies": {
"openssl": "~>1.1.6+1.0.1g",
"vibe-d": "~>0.8.1",
}
I really want to solve linking error first. I tried installing
openssl it didn't help. Any suggestions?
Regards
Erdem
One liner alternatives for initing and pushing some values into array
I need to init and push some values into a array something like:
//DMD64 D Compiler 2.072.2
import std.stdio;
import std.array;
void main()
{
bool a = true;
bool b = false;
bool c = false;
bool[] boolList;
auto boolListAppender = boolList.appender();
boolListAppender ~= [ a, b, c];
}
Live example : http://rextester.com/TJLIXU71426
My question is about
bool[] boolList;
auto boolListAppender = boolList.appender();
boolListAppender ~= [ a, b, c];
I could do the same in one line with C++:
bool boolList[] = { a, b, c };
D alternative(at least my D alternative) seem long. Is there any
better way for
initialing and pushing values at the same time.
Erdem
Re: Lambda cannot access frame of function
On Saturday, 18 November 2017 at 14:30:29 UTC, Adam D. Ruppe wrote: On Saturday, 18 November 2017 at 14:22:19 UTC, kerdemdemir wrote: bool foo( bool function( double ) controlFoo ) Change that `function` to `delegate` and it should work. Function pointers aren't allowed to access other locals, but delegates are. Yes it worked as you suggested. Thanks.
Re: Json
I am using vibe.d's json(http://vibed.org/api/vibe.data.json/) module without a problem and really happy with it. There are also some examples(https://github.com/vibe-d/vibe.d/tree/master/examples/json). If you are using "dub" package manager it is also very easy to integrate vibe.d.
Lambda cannot access frame of function
//DMD64 D Compiler 2.072.2
import std.stdio;
bool foo( bool function( double ) controlFoo )
{
return controlFoo(5.0);
}
void foo2( double val )
{
writeln ( foo( a => a > val ) );
}
void main()
{
foo2(20);
writeln("Hello, World!");
}
Does not compile and gives this errors:
source_file.d(12): Error: function source.foo2.__lambda2 cannot
access frame of function source.foo2
source_file.d(12): Error: function source.foo (bool
function(double) controlFoo) is not callable using argument types
(void)
Live example:
http://rextester.com/WRKCWR55408
Is there any workaround for that?
Regards
Erdem
Re: Removing some of the elements from vibe.core.concurrency.Future[] futurelist
I'd take a look at why the error message says
`Future!(UserData)[]) to Future!(AnalyzeData)[]`
is AnalyzeData the type returned by ProcessResponceData?
Alternatively you could use a singly linked list and splice out
elements that pass the filter predicate. I think you'd have to
roll your own though.
I am sorry Wilson I normally in my code UserData is AnalyzeData =
UserData but I replace the name to make it more understandable.
For now I solved my problem like
vibe.core.concurrency.Future!(UserData)[] futurelist;
foreach( elem; elemList )
{
auto future = vibe.core.concurrency.async(
&elem.makeWebRequest );
futurelist ~= future;
}
int maximumSleepTime = 0;
while(futurelist.any!(a => !a.ready())) //--> Blocking until all
of them ready
{
maximumSleepTime++;
sleep(10.msecs);
if ( maximumSleepTime > 2000 )
return;
}
futurelist.each!(a=> Process(a.getResult()));
Unfortunately that is really bad when I make 250 web requests and
only one of them is bad(I mean not ready). And 249 request have
to wait for the bad one.
I will take a deeper look to data structure you suggested.
Thanks
Removing some of the elements from vibe.core.concurrency.Future[] futurelist
I am trying to make non blocking web requests to a web service.
vibe.core.concurrency.Future!(UserData)[] futurelist;
// I will make http requests in for loop and push them to
futureList
foreach( elem; elemList )
{
// In makeWebRequest I make the httprequest, parse json
and push to my UserData
auto future = vibe.core.concurrency.async(
&elem.makeWebRequest );
futurelist ~= future;
}
// I want to do call ProcessResponceData for each future which is
ready.
while ( futurelist.length > 0 )
{
futurelist.filter!(a => a.ready()).each!(a=>
ProcessResponceData(a.getResult()));
//! Here is my problem
//! I want to remove the futures which are already
processed.
futurelist = futurelist.filter!(a => !a.ready()).array;
sleep(10.msecs);
}
I am having troubles while trying to remove the future which I
already processed.
futurelist = futurelist.filter!(a => !a.ready()).array; results
with:
/usr/local/bin/../import/std/array.d(2716,20): Error: can't have
array of nothrow @safe void()
/usr/local/bin/../import/std/array.d(2782,46): Error: can't have
array of inout nothrow @safe void()
/usr/local/bin/../import/std/array.d(3158,1): Error: template
instance std.array.Appender!(Future!(UserData)[]) error
instantiating
/usr/local/bin/../import/std/array.d(133,32):instantiated
from here: appender!(Future!(UserData)[])
futurelist = futurelist.filter!(a => !a.ready()); results with:
Error: cannot implicitly convert expression (filter(futurelist))
of type FilterResult!(__lambda5, Future!(UserData)[]) to
Future!(AnalyzeData)[]
Do you have any suggestion or workaround for my case?
What lesson I should learn from this case? Do you guys have any
idea why I am getting those compile errors?
Thanks
Erdem
Re: debugging in vs code on Windows
On Friday, 13 October 2017 at 12:55:09 UTC, piotrklos wrote: I have windows 10, VS Code with code-d and C/C++ language extensions. I try to debug but it doesn't work. In particular, the debugging doesn't stop on breakpoints. It exits immediately. I recompile with -m64 and -g. I use dub to build the project. I use unit-threaded and I'm trying to debug a unittest build. Has anyone been able to debug in VS code on Windows? What am I doing wrong? (Rhetorical) Why is dlang community provide so many options (see https://wiki.dlang.org/Debuggers) and **every single one** of them is faulty in some way? I tried windbg and mago-mi but didn't gen anywhere. I am using VisualD(https://github.com/dlang/visuald/releases) with vs2015 community version(free) and I can debug. I highly recommend it if you haven't tried yet. Those options like "-g" is presented to you with interfaces. Forexample "-g" is automatically is being added if you are selecting debug builds(like Debug DMD or Debug LDC).
Re: Need importing dcompute.lib into my project
On Friday, 13 October 2017 at 16:36:06 UTC, Ali Çehreli wrote: On 10/13/2017 08:47 AM, kerdemdemir wrote: > I changed my dependency setting in dub file to "dcompute": "~>0.0.0" but > still getting the same error message. By the way I am sure my LDC > version is good because I can build DCompute source code with same LDC > version. Could this be related to difference in platform like Windows vs. Linux? If so, may be it makes sense to work in a VM that has Nicholas's exact setup. Ali It make sense for me to switch back to linux. I ruined my multiboot linux system which has only 20gb root partition while trying to install CUDA libraries(which takes a lot of space.). Maybe as you suggest instead of trying with windows I need to reinstall my linux.
Re: Need importing dcompute.lib into my project
On Sunday, 8 October 2017 at 07:51:12 UTC, Nicholas Wilson wrote:
On Saturday, 7 October 2017 at 10:34:15 UTC, kerdemdemir wrote:
do you set "-mdcompute-targets=cuda-xxx" in the dflags for
your dub.json for your project?
I have added now after your comment.
But it seems it didn't changed anything.
Here is the dub.json file I have:
{
"name": "dsharpear",
"authors": [
"Erdem"
],
"dflags" : ["-mdcompute-targets=cuda-210" ,"-oq", "-betterC"],
"dependencies": {
"dcompute": ">=0.0.0-alpha0 <0.1.0"
},
"description": "Beamforming with D ",
"copyright": "Copyright © 2017, Erdem",
"license": "proprietary"
}
And running "dub build --compiler=D:\LDCDownload\bin\ldc2.exe
--force" fails with:
Performing "debug" build using D:\LDCDownload\bin\ldc2.exe for
x86.
derelict-util 2.1.0: building configuration "library"...
derelict-cl 2.0.0: building configuration "library"...
derelict-cuda 2.0.1: building configuration "library"...
..\..\..\..\..\AppData\Roaming\dub\packages\derelict-cuda-2.0.1\derelict-cuda\source\derelict\cuda\runtimeapi.d(816,5):
Deprecation: constructor derelict.cuda.runtimeapi.dim3.this
all parameters have default arguments, but structs cannot have
default constructors.
dcompute 0.0.0-alpha0: building configuration "library"...
Targeting 'i686-pc-windows-msvc' (CPU 'pentium4' with features
'')
Building type: real
Building type: uint
Building type: char
Building type: ubyte
Building type: ulong
Building type: int
Building type: double
Building type: long
Building type: ushort
Building type: wchar
Building type: byte
Building type: short
Building type: float
Building type: dchar
..\..\..\..\..\AppData\Roaming\dub\packages\dcompute-0.0.0-alpha0\dcompute\source\dcompute\std\package.d(6,5):
Error: static assert "Need to use a DCompute enabled compiler
See https://github.com/thewilsonator/ldc/tree/dcompute";
D:\LDCDownload\bin\ldc2.exe failed with exit code 1.
You are using an old DCompute: that message was changed in
https://github.com/libmir/dcompute/commit/cf1420d5377c48f9132f1a9a0f8f06ebb46a6433#diff-b0637c2cde07f2ec8f77f9e3d379fff7
I'm not quite sure how the dub version specs work but I believe
"dcompute": "~>0.0.0" should work, or you can force it to use
master.
I'm still not sure why it fails with that error though, are you
using an old LDC as well? 1.4.0 should work.
I changed my dependency setting in dub file to "dcompute":
"~>0.0.0" but still getting the same error message. By the way I
am sure my LDC version is good because I can build DCompute
source code with same LDC version.
Re: Need importing dcompute.lib into my project
On Saturday, 7 October 2017 at 12:12:10 UTC, kinke wrote: On Saturday, 7 October 2017 at 09:04:26 UTC, kerdemdemir wrote: Error: static assert "Need to use a DCompute enabled compiler" Are you using latest LDC 1.4? The CUDA backend wasn't enabled for earlier versions. Yes I am. Actually I can build dcompute's source code so I am sure LDC version is good. Now I am trying to use dcompute within my project.
Re: Need importing dcompute.lib into my project
do you set "-mdcompute-targets=cuda-xxx" in the dflags for your
dub.json for your project?
I have added now after your comment.
But it seems it didn't changed anything.
Here is the dub.json file I have:
{
"name": "dsharpear",
"authors": [
"Erdem"
],
"dflags" : ["-mdcompute-targets=cuda-210" ,"-oq", "-betterC"],
"dependencies": {
"dcompute": ">=0.0.0-alpha0 <0.1.0"
},
"description": "Beamforming with D ",
"copyright": "Copyright © 2017, Erdem",
"license": "proprietary"
}
And running "dub build --compiler=D:\LDCDownload\bin\ldc2.exe
--force" fails with:
Performing "debug" build using D:\LDCDownload\bin\ldc2.exe for
x86.
derelict-util 2.1.0: building configuration "library"...
derelict-cl 2.0.0: building configuration "library"...
derelict-cuda 2.0.1: building configuration "library"...
..\..\..\..\..\AppData\Roaming\dub\packages\derelict-cuda-2.0.1\derelict-cuda\source\derelict\cuda\runtimeapi.d(816,5):
Deprecation: constructor derelict.cuda.runtimeapi.dim3.this
all parameters have default arguments, but structs cannot have
default constructors.
dcompute 0.0.0-alpha0: building configuration "library"...
Targeting 'i686-pc-windows-msvc' (CPU 'pentium4' with features '')
Building type: real
Building type: uint
Building type: char
Building type: ubyte
Building type: ulong
Building type: int
Building type: double
Building type: long
Building type: ushort
Building type: wchar
Building type: byte
Building type: short
Building type: float
Building type: dchar
..\..\..\..\..\AppData\Roaming\dub\packages\dcompute-0.0.0-alpha0\dcompute\source\dcompute\std\package.d(6,5):
Error: static assert "Need to use a DCompute enabled compiler
See https://github.com/thewilsonator/ldc/tree/dcompute";
D:\LDCDownload\bin\ldc2.exe failed with exit code 1.
Re: Need importing dcompute.lib into my project
You should add DCompute as a DUB dependancy. Hi, I inited my project with Dub by unsing "dub init DSharpEar" and I added dependency "dcompute". Even I give extra parameters for using ldc. dub build --compiler=D:\LDCDownload\bin\ldc2.exe --force I am getting : Error: static assert "Need to use a DCompute enabled compiler" Any suggestions? Regards Erdem
Re: For fun: Expressive C++ 17 Coding Challenge in D
I am a total beginner but I want to post that a lot.
auto autoCorrelation(R)(R range)
if (isRandomAccessRange!R)
{
import std.numeric : fft, inverseFft;
import std.range : chain, repeat, zip, dropBack;
import std.algorithm : map;
import std.complex;
auto residual = residualPowerOf2(range.length);
auto fftResult = range.chain(repeat(0, residual)).fft();
auto autoCorrResult = fftResult.zip(fftResult.map!(a =>
a.conj())).
map!( a=> a[0] * a[1] ).
inverseFft().
dropBack(residual).
map!( a => a.re );
return autoCorrResult;
}
I implemented auto correlation in C++ before which is I believe
2~3 time bigger(also I needed to compile fftw, lapack etc.. ) :
https://forum.kde.org/viewtopic.php?f=74&t=118619 .
That was the moment I feel in love with D.
Need importing dcompute.lib into my project
Hi, I have a cuda kernel already working in my cpp project(https://github.com/kerdemdemir/CUDABeamformer/blob/master/CudaBeamformer/kernel.cu) I am trying to convert this to D with using DCompute. I already compiled the DCompute source code and have dcompute.lib. But I am really not good with using libraries and don't know how to use DCompute in my D project(https://github.com/kerdemdemir/DSharpEar/tree/master/DSharpEar). I am not using DUB and compiling with VisualD. Can you guys please help with importing DCompute into my project? Regards Erdem
Error 16: Index Range error while building examples from D Web development
Hi, Thanks its price dropped to 10 Euros I bought the the D Web Development book and I were trying to build some examples. The example in Chapter3 called noteapp4 is giving me this error : Performing "debug" build using dmd for x86. noteapp4 ~master: building configuration "application"... C:\Users\Erdem\AppData\Roaming\dub\packages\vibe-d-0.7.32\vibe-d\source\vibe\http\server.d(286,33): Deprecation: alias diet.traits.FilterCallback is deprecated - Use SafeFilterCallback instead. Compiling Diet HTML template create.dt... Compiling Diet HTML template listnotes.dt... Linking... OPTLINK (R) for Win32 Release 8.00.17 Copyright (C) Digital Mars 1989-2013 All rights reserved. http://www.digitalmars.com/ctg/optlink.html .dub\build\application-debug-windows-x86-dmd_2075-102ED5AC10E8F023CF2D8D690787ADD9\noteapp4.obj(noteapp4) Offset 23F7EH Record Type 009D Error 16: Index Range Error: linker exited with status 1 dmd failed with exit code 1. Meanwhile hello world example compiling. I am on windows 10 and C:\D\dmd2\windows\bin>dmd.exe --version DMD32 D Compiler v2.075.0 Do you guys have any idea about what I am doing wrong? Thanks
Re: Efficiently streaming data to associative array
I haven't yet dug into formattedRead but thx for letting me
know : )
I was mostly speaking about the pattern with the AA. I guess
the best I can do is a templated function to hide the ugliness.
ref Value GetWithDefault(Value)(ref Value[string] map, const
(char[]) key) {
auto pValue = key in map;
if(pValue) return *pValue;
return map[key.idup] = Value.init;
}
void main() {
size_t[string][string] indexed_map;
foreach(char[] line ; stdin.byLine) {
char[] a;
char[] b;
size_t value;
line.formattedRead!"%s,%s,%d"(a,b,value);
indexed_map.GetWithDefault(a).GetWithDefault(b) = value;
}
indexed_map.writeln;
}
Not too bad actually !
As a total beginner I am feeling a bit not comfortable with basic
operations in AA.
First even I am very happy we have pointers but using pointers in
a common operation like this IMHO makes the language a bit not
safe.
Second "in" keyword always seemed so specific to me.
I think I will use your solution "ref Value
GetWithDefault(Value)" very often since it hides the two things
above.
Best syntax for a diagonal and vertical slice
We have awesome way for creating slices like: a = new int[5]; int[] b = a[0..2]; But what about if I have 2D array and I don't want to go vertical. Something like : int[3][3] matrix = [ [ 1, 2, 3 ], [ 4, 5, 6 ], [ 7, 8, 9 ] ]; I believe I can use std.range function "RoundRobin"(or maybe it won't work with 2D array directly) for having a good looking vertical slice which will have 1,4,7 or 2,5,8 or 3,6,9 in my example above. And what if I want to go diagonal like 1,5,9 or 3,5,7 in the example above. Is there a good solution in std without using for loops? I have one more requirement for fulfilling the task that I working on. This slices do not have to be the same size as the array. For example in the example above slice size could have 2 instead of 3. In this case I need to have slices like 1,5;2,6;4,8;5,9 ... and so on for diagonal case. Erdem Ps: Converting the 2D array to 1D array is possible in my case.
Re: Avoid if statements for checking neighboring indexes in a 2D array
As for the problem itself, it can be solved without finding connected components. I won't post the solution right away because it is potentially a spoiler. See http://codeforces.com/blog/entry/53268 for problem analysis (828B) and http://codeforces.com/contest/828/submission/28637184 for an example implementation in D. Ivan Kazmenko. Wow I understand the question wrongly than, B W WWWBB WWBWW I excepted there should be two B squares here. One 3*3 and another 1*1. And my answer would be 6 instead 12 here. Yes if there can be only one black square than my solution would be much more simple. One good thing about D community is when I ask a question here you guys are really nice that I get inspired. Thanks Ivan
Re: Avoid if statements for checking neighboring indexes in a 2D array
Of course now I will try to have it work first. Than replace for loops with Cartesian product calls. Than I will make 2D array template and even maybe with random access range. And finally for being able to use this class later in the some other coding challenge I will make Searching( == 'W' part) and Process functions passed by parameter. Thanks a lot for help. Erdem
Re: Avoid if statements for checking neighboring indexes in a 2D array
Hi Guys,
@Nicholas , thanks a lot for cool solution but actually I weren't
working on image processing. I was trying to solve
"http://codeforces.com/contest/828/problem/B";. I really needed
finding connected components this time.
@Ivan, your solution is much more elegant than what I did. But I
find @Timon's solution with cartesian product a bit nicer in this
case since I love to see std function more and more.
Thanks guys for all your advises. D community is really the best.
Here is my solution to question. It seems I didn't get it working
completely yet. In my debugger(Msvc MonoD) even there are many
rows it seems Recurse function only loops the columns in the
first row. And debugger is jumping so strangely I couldn't tag
the problem.
But I don't expect a big change there should be a small bug that
is it.
Sorry if code contains some foreign words I just replaced many
variable names from my native language I might be missing some.
import std.stdio;
import std.string;
import std.algorithm;
import std.conv;
import std.array;
import std.range;
import std.math;
int totalrow;
int totalcolumn;
dchar[][] twoDimensionArray;
struct ConnectedElementsSolver
{
this( dchar[][] twoDimArray )
{
m_twoDimStruct = twoDimArray;
Recurse(0, 0);
}
void Recurse ( int row, int column )
{
if( row < 0 || column < 0 )
return;
for ( ; row < m_twoDimStruct.length ; row++ )
{
for ( ; column < m_twoDimStruct[row].length; column++
)
{
Process( row, column, m_twoDimStruct.length,
m_twoDimStruct[row].length );
}
}
}
void Process( int row, int column, ulong maxrow, ulong maxcolumn
)
{
if( row < 0 || column < 0 || row >= maxrow || column >=
maxcolumn )
return;
if ( m_twoDimStruct[row][column] == 'B' )
{
m_twoDimStruct[row][column] = 'W';
m_tempResult.Process(row, column );
Process(row-1,column-1, maxrow, maxcolumn);
Process(row,column-1, maxrow, maxcolumn);
Process(row+1,column-1, maxrow, maxcolumn);
Process(row-1,column, maxrow, maxcolumn);
Process(row+1,column, maxrow, maxcolumn);
Process(row-1,column+1, maxrow, maxcolumn);
Process(row,column+1, maxrow, maxcolumn);
Process(row-1,column+1, maxrow, maxcolumn);
}
else
{
if ( m_tempResult.HowManyFilled )
m_results ~= m_tempResult;
m_tempResult.Resetle();
}
}
SquareCandidate m_tempResult;
SquareCandidate[] m_results;
dchar[][] m_twoDimStruct;
}
struct SquareCandidate
{
int MaxY;
int MinY;
int MaxX;
int MinX;
int HowManyFilled;
this( int howManyFilled )
{
HowManyFilled = howManyFilled;
}
void Resetle()
{
this = SquareCandidate();
}
void Process( int row, int column )
{
HowManyFilled++;
MaxY = max( column, MaxY);
MinY = min( column, MinY);
MaxX = max( row, MaxX);
MinX = min( row, MinX);
}
int FindEmptySlots()
{
int kareKenarUzunlugu = max(MaxX-MinX, MaxY-MinY);
int kareAlani = kareKenarUzunlugu*kareKenarUzunlugu;
return kareAlani - HowManyFilled;
}
bool CanCreateSquare( int xMax, int yMax )
{
int xUzunlugu = MaxX-MinX;
int yUzunlugu = MaxY-MinY;
if ( xUzunlugu > yUzunlugu )
{
return yMax >= xUzunlugu;
}
else
{
return xMax >= yUzunlugu;
}
}
}
void main()
{
auto dimensions = stdin.readln.strip.split().map!(a =>
to!int(a)).array();
totalrow = dimensions[0];
totalcolumn = dimensions[1];
twoDimensionArray = stdin
.byLine()
.take(totalrow)
.map!(line => line
.map!(a => to!dchar(a))
.array())
.array;
ConnectedElementsSolver baglantiliElemCozucu =
ConnectedElementsSolver(twoDimensionArray);
bool isAnyProblemMakingSquare =
baglantiliElemCozucu.m_results.any!(a =>
a.Ca
Avoid if statements for checking neighboring indexes in a 2D array
My goal is to find connected components in a 2D array for example
finding connected '*'
chars below.
x x x x x x
x x x x x x
x x * * x x
x x * * x x
x x x * * x
* x x x x x
There are two connected '*' group in this example. First group is
composes of six '*' located closer to middle and the second group
composes only one '*' char located in the left bottom corner.
Do to this I generally implement a recursive algorithm which
repeat calling the same function by checking all neighbors around
the current index. I generally end up with something like :
void foo( int row, int col)
{
//Do something here like caching the index
if ( twoDimensionData[row - 1][col] == '*')
foo(row- 1, col);
else if ( twoDimensionData[row + 1][col] == '*')
foo(row+ 1, col);
else if ( twoDimensionData[row - 1 ][col - 1] == '*')
foo(row - 1, col - 1);
//. I need 5 more of this bad boys I mean if checks
}
Is there any better way to achieve this with cool std functions
like enumerate or iota without needing to write eight if checks?
VisualD building with GDC setting library path
Hi, I am tring to build Cristi Cobzarenco's fork of Scid which has LAPACK,BLAS dependency. I add all modules of Scid to my project and I am tring to build it within my project. I add LibraryFiles: liblapack.a libblas.a libtmglib.a libgfortran.a etc.. via menu configuration properties-->Linker --> General ---> LibraryFiles . Even though I set "C:\Qt\Tools\mingw491_32\i686-w64-mingw32\lib" path which has libgfortran.a from Visual D Settings -->Library Paths; I am getting error : gdc: error: libgfortran.a: No such file or directory. Libraries only works if I copy and paste them to my project folder. And coping all libraries fortran.a , pthread.a etc... seems not logical to me. I read there is a known isssue with sc.ini but it should only be with DMD not with GDC. How can I set library path with visualD while building with GDC?
Re: Getting Nth Row and Column from MatrixView, Scid library
Sad times with linear algebra libraries for me, Since I can't get rows and columns easily with Scid, It seems not flexible for me. And also there are other issues for example I can't set matrix to row or column major. I begin to check alternatives first I begin to investigate Dlib. D lib matrixes are unfortunately static once created their size can't be expanded and must be square matrix. This restrictions seem too much to me . The best alternative seems to me scid fork of "Cristi Cobzarenco" link: https://github.com/cristicbz/scid. It has the basic features I need. But it seems last commit made 3 years ago. I couldn't compile it. I am getting error: scid\internal\regionallocator.d(364): Error: safe function 'scid.internal.region allocator.threadLocalSegmentSize' cannot call system function 'scid.internal.reg ionallocator.RegionAllocatorException.this' Error building library Any advice about another lib or fix compile error will be welcome.
Getting Nth Row and Column from MatrixView, Scid library
Hi, I want to use Scid matrixes for implementing GMM algorithm. I will start by writing Naive Bayes with linear and quadratic decision boundaries . I reliaze Scid does not provides any functions for getting spesific row or coloumn. Matrixwview class only supplies opIndex function. Is there anything that I am missing or what is the best to get nth column or row with Scid library. Link to Scid lib: http://www.kyllingen.net/code/scid/doc/scid_matrix.html
Linear algebra library with no dependency & Why every linear algebra library has LAPACK dependency
This question is not only about "D linear algebra libraries" but also for other linear algebra libraries in other languages. I am working with some scientific developers in my current project. When we were talking I said "I know a great linear algebra library LAPACK" but my friend who is very experienced about numeric told me LAPACK isn't the best library for performance especially if matrix is sparse. In fact he said every numeric developer will try to avoid LAPACK. Now I want to implement some statistical methods like Bayes, GMM. And I need a linear algebra library. I am looking for a native "module" code which I can directly include my project without dll or I am looking for a library without any dependency. But I see all linear algebra libraries has dependency to LAPACK. I am sure I am asking this question because I am lacking domain information about maths and linear algebra. But why all libraries has dependency to LAPACK. What make LAPACK irreplaceable ? Ps: I am not sure if asking questions related to D but not %100 about D is a bad habit. If it is please warn me.
Re: Autocorrelation function with ranges
On Saturday, 27 June 2015 at 12:17:31 UTC, Timon Gehr wrote: This computes a²·a̅ instead of a·a̅. What is the source code for residualPowerOf2? Also is there any performance issues? can I make this faster? Probably you should use http://dlang.org/phobos/std_complex.html#.sqAbs instead. You then also don't need the final map to extract the real part. You are absulately right instead fftResult.zip(fftResult.map!(a => a * a.conj())) I corrected it to fftResult.zip(fftResult.map!(a => a.conj())) Thanks a lot
Re: Autocorrelation function with ranges
On Saturday, 27 June 2015 at 10:37:08 UTC, Rikki Cattermole wrote: No idea about the maths behind it are but: Thanks a lot for your answer anyway. I am hoping even not related with D directly, this discussions may atract people from other languages to D while looking for Domain information. chain(autoCorrResult[1..$/2]) Should that one be a zero? I found this link below. "http://www.aip.de/groups/soe/local/numres/bookcpdf/c13-2.pdf"; Which says : The correlation at zero lag is in r0, the first component; the correlation at lag 1 is in r1, the second component; the correlation at lag −1 is in rN−1, the last component; etc. Correlation result after IFFT is like : 0 1 2 3 . T -1 -2 -3 -T How I wanted to be : -T -T+1 .-1 0 1 T-1 T After reading the link I think you are right, auto finalResult = chain(autoCorrResult[$/2..$]). chain(autoCorrResult[0..$/2]). map!(a => a.re); Example above should be the way how I transform. Also now I see inverseFft(). dropBack(residual); ==> DropBack may not be a good idea here. I will think about it
Autocorrelation function with ranges
Hi
My question is more about Maths than D lang,
I am hoping, maybe somebody worked with AutoCorrelation function
before.
auto autoCorrelation(R)(R range)
if (isRandomAccessRange!R)
{
auto residual = residualPowerOf2(range.length); // Find how
many zeros to add
auto fftResult = range.chain(repeat(0, residual)).fft(); //
Takes FFT
//First zip each element of fft with conjagute of fft
auto autoCorrResult = fftResult.zip(fftResult.map!(a => a *
a.conj())).
map!( a=> a[0] * a[1] ). // Than multiple them
inverseFft(). // Than take inverse
dropBack(residual);//Drop the additional zeros
auto finalResult = autoCorrResult.take(1). // Take DC element
chain(autoCorrResult[$/2..$]).//Take last half to
beginning
chain(autoCorrResult[1..$/2]). // First(negative lags)
to end
map!(a => a.re); // I just need real part
return finalResult ;
}
My autocorrelation method return some crazy values(finalResult[0]
= -101652). I am mostly suspicious about calculations to set
"finalResult" variable.
Also is there any performance issues? can I make this faster?
Using C library libsndfile with D
Hi I want to read wav files. I thought I can use libsndfile since I am quite familiar with it. I downloaded the project from. https://github.com/D-Programming-Deimos/libsndfile I add the sndfile.di file to my project. I thought I could directly use libsndfile.dll since D directly supports C. But I am getting link errors. Can I use a C DLL directly ? Do I have to add anything to my dub.json file if dll is my project file ? What is "Deimos" stands for ? Is it collections of bindings ? Does community supports "Deimos" projects?
Re: Passing functions as template parameter and assigning default values to them
On Sunday, 21 June 2015 at 10:06:15 UTC, biozic wrote:
You can use a template alias parameter with a default value
that is your default lambda:
int indexOfMax(alias fun = a => a, R)(R range)
{
// Use `fun` here like a function.
}
-- Nico
Thanks a lot, it works !!
Passing functions as template parameter and assigning default values to them
Hi,
I need to find the index of maximum element so my code:
int indexOfMax(R)(R range)
{
alias Type = typeof(range.front().re); > I don't like
.re here
Type max = 0;
size_t maxIndex = 0;
foreach ( index,elem; range )
{
if ( elem.re > max )-> And also here
{
max = elem.re;
maxIndex = index;
}
}
return maxIndex;
}
Since my range contains Complex!double types I have to add ".re"
for current implementation. But I want to be more generic. Like
how std.algorithm.map is.
Like: range.map!(a => a.re).
So what I want to achive is :
indexOfMax!(a => a.re)(complexRange); > implement algorithm
on a.re
indexOfMax(intRange); -> if a function is not given act like
(a => a)
Any advice with template function parameters or mixins will make
me happy.
Regards
Erdem
Re: appender!(dchar[]) put fail
On Saturday, 13 June 2015 at 13:09:20 UTC, Dennis Ritchie wrote:
auto stringB = readln.chomp.map!(to!dchar).array;
auto stringC = readln.chomp.map!(to!dchar).array;
auto charAppender = appender!(dchar[][]);
auto totalStr = stringB.repeat(3).chain(stringC.repeat(5));
charAppender.put(totalStr);
writeln(charAppender);
charAppender.put("c"d.dup);
charAppender.put("test"d.dup);
writeln(charAppender);
Thanks lot that is really good.
One more question I am asking those kind of questions to
understand and not ask same stuff over and over, :
auto totalStr = chain(stringB.replicate(bCount),
stringC.replicate(cCount));
writeln(typeof(totalStr.array()).stringof);
>dchar[]
But
auto totalStr = chain(stringB.repeat(bCount),
stringC.repeat(cCount));
writeln(typeof(totalStr.array()).stringof);
>dchar[][]
It seems to me a little inconsistent. range.repeat and
array.replicate gives result in difference dimension.
Is there any explanation or logic that I am missing which results
this behaviour?
Re: appender!(dchar[]) put fail
It is the same, but totalStr is not a dchar[]. It's a Result (a type internal to the chain function ) which is a range. The foreach loop iterates over Result, which returns dchar[]. So if you try to do something like that : charAppender.put(totalStr.array), it won't work because totalStr.array is a dchar[][]. Sorry to making the discussion longer and wasting your times. But I am looking for a way without for loops. Also looping every element one by one does not seems very efficient to me. Any advices for that?
Re: appender!(dchar[]) put fail
The problem is that your appender is a char appender, and you
try to put a dstring into it. Replace :
charAppender.put(totalStr);
by :
foreach(elem; totalStr){
charAppender.put(elem);
}
elem will be a dchar, so it will work.
But I can see in the example of
array.appander(http://dlang.org/phobos/std_array.html#appender)
int[] a = [ 1, 2 ];
auto app2 = appender(a);
app2.put(3);
app2.put([ 4, 5, 6 ]); ---> appender accepts another array.
Why this is not same with dchar ?
appender!(dchar[]) put fail
I have two strings(stringB,stringC) which I need to repeat(bCount
times, cCountTimes) and then chain.
auto charAppender = appender!(dchar[]);
auto totalStr =
stringB.repeat(bCount).chain(stringC.repeat(cCount));
This compiles and works ok,
But when I try to append new string to charAppender :
charAppender.put(totalStr);
Error: template std.array.join cannot deduce function from
argument types
I tried:
charAppender.put(totalStr.array());
charAppender.data.chain(totalStr);
charAppender.data.chain(totalStr.array()); etc...
I always get compile errors.
Do you have any idea or fix about that?
Also what is the difference between algorithm.joiner without
seperator and range.chain?
As requested before, this time I will copy full code,
int[dchar] mapA;
int includeCounter(T)(T tuple)
{
int curMax = 10;
foreach ( elem ; tuple )
{
int numberInA = 0;
if (elem[0] in mapA)
numberInA = mapA[elem[0]] ;
else
{
curMax = 0;
break;
}
if ( numberInA < elem[1] )
{
curMax = 0;
break;
}
else
{
auto newCount = numberInA / elem[1];
if ( newCount < curMax )
curMax = newCount;
}
}
if (curMax > 0)
{
foreach ( elem ; tuple )
{
mapA[elem[0]] -= curMax;
}
}
return curMax;
}
void readInput()
{
size_t lineSize;
auto stringA = stdin.readln.chomp().map!( a =>
to!dchar(a)).array();
auto stringB = stdin.readln.chomp().map!( a =>
to!dchar(a)).array();
auto stringC = stdin.readln.chomp().map!( a =>
to!dchar(a)).array();
foreach ( elem ; stringA)
mapA[elem]++;
auto tupleB = stringB.group();
auto tupleC = stringC.group();
auto bCount = includeCounter( tupleB );
auto cCount = includeCounter( tupleC );
auto charAppender = appender!(dchar[]);
foreach ( elem ; mapA.keys)
{
int* count = &mapA[elem];
if ( *count > 0)
{
while((*count)--)
charAppender.put(elem) ;
}
}
auto totalStr =
stringB.repeat(bCount).chain(stringC.repeat(cCount));
charAppender.put(totalStr);
}
void main( string[] args )
{
readInput();
}
Re: Reading array of integers readln performance issues
Thanks a lot for your great advices and exaamples. Yes if I don't return; web-site won't show it as "wrong answer". As a learner I am very happy with the responsiveness of the community. Regards
Re: How to pass voldemort types to functions
void foo(R)(R range)
if (isInstanceOf!(Tuple, ElementType!R))// <-- optional
{
Ali thanks a lot. I don't believe I didn't simply try your way.
It works.
I am also happy to learn optional static if . Your examples are
really useful for me.
Next time I will share whole code.
Thanks a lot.
How to pass voldemort types to functions
Hi; I have tuples created by std.algorithm.group function. auto tupleB = stringB.group(); I need to write a a function which takes tubleB and do some cool stuff. If I don't use a function and write all code below .group() everytihng works but for reusing the code I want to call a function with my tuples. I tried ; void foo(T...)(T tuple) void foo(Tuple!(dchar,uint) tuplle) But even couldn't compiile. Do you have any idea for passing result of std.algorithm.group() to my free function?
Reading array of integers readln performance issues
Hi;
To learn D better and challanging myself I am tring code
computation's with D.
There is a question which is about reading a line of integer
which consist of 20 elements.
My solution fails because "Time limit exceeded", I thought it is
because of my algorithm first. I realize time limit is exceeded
even before my algorithm starts while reading line of integers. I
understand this by giving a wrong answer to question after readln
statement. I did that to get a "wrong answer error" but my code
still get a "Time limit exceed" error because "readln" takes very
long time.
Can I achieve something faster than code below?
auto peopleMoney = stdin.readln().split().map!(a =>
to!int(a)).array();
if (peopleMoney.length == 20)
writeln(":(");
Regards
Erdem
Ps: I do not want to bore you with long code, but I am sending
link to whole program anyway if anyone need.
http://codeforces.com/contest/549/submission/11537206
Re: Writeln does not prints if array has more than 500 elements
I am running DMD on windows, my DMD version is DMD32 V2.067.1. It might be because I installed 32bit version on 64bit windows.
Writeln does not prints if array has more than 500 elements
Hi
Following code works
int[] peopleMoney = iota(0, 500, 1).array();
writeln(peopleMoney.map!(a => to!string(a)).joiner(" "));
=> 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 ...
It writes the contents to std.output as expected.
But if I change 500 to 600 nothing is being printed.
int[] peopleMoney = iota(0, 600, 1).array();
writeln(peopleMoney.map!(a => to!string(a)).joiner(" "));
==> NOTHİNG PRINTS
What am I doing wrong?
Re: Woldemort Type can't even call "take" or "array"
Unfortunately not this time :) import std.stdio; import std.algorithm; import std.string; import std.conv; import std.array; ---> I added this line thanks to you.
Re: Woldemort Type can't even call "take" or "array"
The solution may be as simple as importing std.array (or std.range) but we can't be sure without a short but complete code. Solution was as simple as importing std.array. Thanks a lot again Ali. Just for curiosity; why can't I use numArr.take(3); source\app.d(33): Error: no property 'take' for type 'MapResult!(unaryFun, FilterResult!(__lambda3, FilterResult!(__lambda2, char[][][])))'.
Re: Woldemort Type can't even call "take" or "array"
And one more question out of curiosity why I couldn't find any method which will return the max element in a range.
Woldemort Type can't even call "take" or "array"
auto outputString = (char[][] inParam) =>
(inParam[0].length == 0 || target.startsWith(inParam[0])) &&
(inParam[1].length == 0 || target.endsWith(inParam[1]));
auto numArr = threeDArr.filter!(a => a[0].canFind('?')).
filter!(a => outputString(a[0].split('?'))).
map!"to!int(a[1])";
writeln(numArr);
I don't want to get into details of my code and bore you.It takes
a 3d array like below:
[["201212?4", "64"], ["20121235", "93"], ["2012123?", "87"],
["2012?234", "75"]]
And returns range of numbers like :
[64, 87, 75]
Now I want to find the maximum of this range "numArr". Since I
couldn't find a "max" function works on ranges I decided to sort
them and take the first element.
But when I tried to sort like numArr.sort();
Error: template std.algorithm.sorting.sort cannot deduce function
from argument types !()(MapResult!(unaryFun,
FilterResult!(__lambda3, FilterResult!(__lambda2, char[][][].
Ok I said I will first copy the range to array then use sort. So
I tried numArr.array
Error: no property 'array' for type 'MapResult!
Now only thing I can do with the range I have to call
writeln();Why other functions of standart library are not working
with this range type?
Re: Appending to multidimensional dynamic array
In your case its pretty simple. The buffer is being reused. So same memory being added multiple times to the candidate. Just slap on a .dup when adding it. candidate ~= line; Thanks a lot replacing the line above with candidate ~= [line[0].dup, line[1].dup]; My problem is solved .
Appending to multidimensional dynamic array
I want to append a 2D array to my 3D array. I expect it should be
same as int[] arr; arr ~= 3;
void readInput()
{
char[][][] candidate;
char[] buff;
size_t counter = 0;
while ( stdin.readln(buff) )
{
char[][] line = buff.chomp().split();
writeln(line);
candidate ~= line;
writeln(candidate);
if (++counter > 1 ) break;
}
}
And I send the inputs below
201212?4 64
20121235 93
I expect a output like
[["201212?4", "64"], ["20121235", "93"]]
But instead I see
[["20121235", "93"], ["20121235", "93"]]
In short :
=~ replaces all the elements in the array with the last added.
Where am I doing wrong? How can I meet my expectation?
By the way I am posting the same question to stackoverflow at the
same time. Does sending questions to stackoverflow as well as
here not desirable for D community? If so I will just write here.
