Re: [Tutor] indexing a list
On Thu, Oct 18, 2012 at 8:01 AM, Spyros Charonis wrote: > > x = 21 # WINDOW LENGTH > > In [70]: SEQ[0:x] > Out[70]: 'MKAAVLTLAVLFLTGSQARHF' > > In [71]: SEQ[x:2*x] > Out[71]: 'WQQDEPPQSPWDRVKDLATVY' > > In [72]: SEQ[2*x:3*x] > Out[72]: 'VDVLKDSGRDYVSQFEGSALG' > > How could I write a function to automate this so that it does this from > SEQ[0] throughout the entire sequence, i.e. until len(SEQ)? In your examples, the lower slice limit is 0x, 1x, 2x, and so on. The upper limit is 1x, 2x, 3x, and so on. That should scream that you need a counter, or range/xrange. The lower limit of the last slice should be less than len(SEQ), such that there's at least 1 item in the last slice. So, in terms of range, the start value is 0, and the stop value is len(SEQ). To make things even simpler, range takes an optional step size. This gives you the 0x, 1x, 2x, etc for the start index of each slice. The upper bound is then i+x (corresponding to 1x, 2x, 3x, etc). For example: >>> seq = 'MKAAVLTLAVLFLTGSQARHFWQQDEPPQSPWDRVKDLATVYVDVLK' >>> x = 21 >>> for i in range(0, len(seq), x): ... print(seq[i:i+x]) ... MKAAVLTLAVLFLTGSQARHF WQQDEPPQSPWDRVKDLATVY VDVLK If you're using Python 2.x, use xrange instead of range, and "print" is a statement instead of a function. You can also use a generator expression to create a one-time iterable object that can be used in another generator, a for loop, a comprehension, or as the argument of a function that expects an iterable, such as the list() constructor: >>> chunks = (seq[i:i+x] for i in range(0, len(seq), x)) >>> list(chunks) ['MKAAVLTLAVLFLTGSQARHF', 'WQQDEPPQSPWDRVKDLATVY', 'VDVLK'] ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
[Tutor] indexing a list
Hello pythoners, I have a string that I want to read in fixed-length windows. In [68]: SEQ Out[68]: 'MKAAVLTLAVLFLTGSQARHFWQQDEPPQSPWDRVKDLATVYVDVLKDSGRDYVSQFEGSALGKQLNLKLLDNWDSVTSTFSKLREQLGPVTQEFWDNLEKETEGLRQEMSKDLEEVKAKVQPYLDDFQKKWQEEMELYRQKVEPLRAELQEGARQKLHELQEKLSPLGEEMRDRARAHVDALRTHLAPYSDELRQRLAARLEALKENGGARLAEYHAKATEHLSTLSEKAKPALEDLRQ' I would like a function that reads the above string, 21 characters at a time, and checks for certain conditions, i.e. whether characters co-occur in other lists I have made. For example: x = 21 # WINDOW LENGTH In [70]: SEQ[0:x] Out[70]: 'MKAAVLTLAVLFLTGSQARHF' In [71]: SEQ[x:2*x] Out[71]: 'WQQDEPPQSPWDRVKDLATVY' In [72]: SEQ[2*x:3*x] Out[72]: 'VDVLKDSGRDYVSQFEGSALG' How could I write a function to automate this so that it does this from SEQ[0] throughout the entire sequence, i.e. until len(SEQ)? Many thanks for your time, Spyros ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Indexing a list with nested tuples
My bad- meant to say [1]. Thanks. -Alexander On Fri, Aug 5, 2011 at 12:36 PM, Christopher King wrote: > > > On Tue, Aug 2, 2011 at 10:44 PM, Alexander Quest wrote: >> >> have [0] to indicate that I want to go to the second value within that >> first item, which is the >> point value >> > Actually [0] is the first element. I would go with [1]. > > > ___ > Tutor maillist - Tutor@python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor > > ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Indexing a list with nested tuples
On Tue, Aug 2, 2011 at 10:44 PM, Alexander Quest wrote: > > have [0] to indicate that I want to go to the second value within that > first item, which is the > point value > Actually [0] is the first element. I would go with [1]. ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Indexing a list with nested tuples
Hi Bob- thanks for the reply again. I apologize about not "replying all"
last time- still getting in the habit of doing this.
I am using Python version 3.1. As far as tuples are concerned, I don't NEED
to use them, but I am trying to get some practice with them. This is because
I am following an instructional book that is discussing nested tuples within
lists.
The way I get the "selection" variable from the user is just by typing the
following: selection = input("Selection: ")
I'm not sure why it reads it initially as a string, but I later included the
line selection = int(selection), which solved the int/str problem.
Also, I was about to switch to dictionaries or just lists without tuples,
but another poster above stated that I could just replace the entire tuple
item within the list, which technically would not be changing the tuple, so
it worked out. The only problem I have now is trying to sort the 4
attributes based on their numerical value, not their alphabetical value. But
when I type in attributes.sort(reverse=True), it sorts them alphabetically
because the name of the attribute is 1st in the list, and its value is 2nd.
Here it is again for reference: attributes = [("strength", 0), ("health ",
0), ("wisdom ", 0), ("dexterity", 0)]
Sorry if this is a bit confusing. Thanks for your help and tips so far Bob.
-Alex
On Wed, Aug 3, 2011 at 5:52 AM, bob gailer wrote:
> On 8/2/2011 11:39 PM, Alexander Quest wrote:
>
> Hey Bob- thanks for the reply. Here is a more complete part of that code
> section (the ellipses are parts where I've deleted code because I don't
> think it's important for this question):
>
>
> Please always reply-all so a copy goes to the list.
>
> Thanks for posting more code & traceback
>
> I forgot to mention earlier - tell us which version of Python you are using
> (this looks like version 3)
>
> You did not answer all my questions! How come? Please do so now.
>
>
>
> _
> attributes = [("strength", 0), ("health ", 0), ("wisdom ", 0),
> ("dexterity", 0)]
> .
> .
> .
> print(
> """
> 1 - Strength
> 2 - Health
> 3 - Wisdom
> 4 - Dexterity
>
> Any other key - Quit
> """
> )
> selection = input("Selection: ")
> if selection == "1" or selection == "2" or selection == "3" or selection ==
> "4":
> print("You have ", points, "points available.")
> how_many = input("How many would you like to add to this
> attribute?: ")
> while how_many < 0 or how_many > 30 or how_many ==
> "": # Because max points available is 30, and
> entering less than 0 does not make sense.
> print("Invalid entry. You have ", points, "points
> available.") # If the user enters a number
> less than 0, greater than 30, or just presses enter, it loops.
> how_many = input("How many would you like to add to
> this attribute?: ")
> print("Added ", points, "to ", attributes[selection-1][0],
> "attribute.") # Here is where I try to add the
> number of points to the value, based on what the user entered.
> points = points -
> how_many
> # I subtract the number of points added from the total points available.
> attributes[selection-1][1] +=
> how_many # I
> add the number of points the user selected to the variable selected.
>
>
> __
>
>
> Here's the traceback I get:
>
> Traceback (most recent call last):
> File "C:\Users\Alexander\Desktop\Python Practice\Ch05-2.py", line 54, in
>
> print("Added ", points, "to ", attributes[selection-1][0],
> "attribute.")
> TypeError: unsupported operand type(s) for -: 'str' and 'int'
> _
>
> Thanks for any help. I understand that I can't change tuples directly, but
> is there a way to change them indirectly (like saying attribute.remove[x]
> and then saying attribute.append[x] with the new variable? But this seems to
> take out both the string and the value, when I only want to increase or
> decrease the value for one of the 4 strings, strength, health, wisdom, or
> dexterity).
>
>
> DON'T USE TUPLES. WHY DO YOU INSIST ON THEM?
>
>
>
>> What does the error message( unsupported operand type(s) for -: 'str' and
>> 'int') tell you?
>
>
> Why would selection be a string rather than an integer?
>
>
> This has to do with how you obtain selection from the user.
>>
>> Why did you expect to be able to alter the value of a tuple element?
>> Tuples are immutable! Use a list instead.
>>
>>
> --
> Bob Gailer919-636-4239
> Chapel Hill NC
>
>
___
Tutor
Re: [Tutor] Indexing a list with nested tuples
Thanks Peter- I tried the replacement method where the entire tuple is
replaced with a new one and that worked. Changing the "attribute_index" (or
"selection" variable, as I called it) to an integer removed the int/str
errors.
-Alex
On Wed, Aug 3, 2011 at 12:12 AM, Peter Otten <__pete...@web.de> wrote:
> Alexander Quest wrote:
>
> > Hi guys- I'm having a problem with a list that has nested tuples:
> >
> > attributes = [("strength", 0), ("health ", 0), ("wisdom ", 0),
> > ("dexterity", 0)]
> >
> > I've defined the list above with 4 items, each starting with a value of
> 0.
> > The player
> > enters how many points he or she wants to add to a given item. The
> > selection menu
> > is 1 - strength; 2 - health; 3 - wisdom; 4- dexterity. So the "selection"
> > variable is actually
> > 1 more than the index location of the intended item. So I have the
> > following code:
> >
> > print("Added ", points, "to ", attributes[selection-1][0], "attribute.")
> >
> > My intent with this is to say that I've added this many points (however
> > many) to the
> > corresponding item in the list. So if the player selects "1", then
> > selection = 1, but I subtract
> > 1 from that (selection -1) to get the index value of that item in the
> list
> > (in this case 0). Then I
> > have [0] to indicate that I want to go to the second value within that
> > first item, which is the
> > point value. I get an error saying that list indices must be integers,
> not
> > strings. I get a similar
> > error even if I just put attributes[selection][0] without the minus 1.
> >
> > Also, it seems that the tuple within the list cannot be modified
> directly,
> > so I can't add points to the original value of "0" that all 4 items start
> > with. Is there a way to keep this nested list with
> > tuples but be able to modify the point count for each item, or will it be
> > better to create a dictionary or 2 separate lists (1 for the names
> > "Strength, Health, Wisdom, Dexterity" and one
> > for their starting values "0,0,0,0")? Any suggestions/help will be
> greatly
> > appreciated!!!
>
> [I'm assuming you are using Python 3. If not replace input() with
> raw_input()]
>
> Let's investigate what happens when you enter an attribute index:
>
> >>> attribute_index = input("Choose attribute ")
> Choose attribute 2
> >>> attribute_index
> '2'
>
> Do you note the '...' around the number?
>
> >>> attribute_index -= 1
> Traceback (most recent call last):
> File "", line 1, in
> TypeError: unsupported operand type(s) for -=: 'str' and 'int'
>
> It's actually a string, not an integer; therefore you have to convert it to
> an integer before you can do any math with it:
>
> >>> attribute_index = int(attribute_index)
> >>> attribute_index
> 2
> >>> attribute_index -= 1
> >>> attribute_index
> 1
>
> Now let's try to change the second tuple:
>
> >>> attributes = [
> ... ("strength", 0), ("health", 0), ("wisdom", 0), ("dexterity", 0)]
> >>> attributes[attribute_index]
> ('health', 0)
> >>> attributes[attribute_index][1] += 42
> Traceback (most recent call last):
> File "", line 1, in
> TypeError: 'tuple' object does not support item assignment
>
> The error message is pretty clear, you cannot replace items of a tuple.
> You can either to switch to nested lists
>
> [["strength", 0], ["health", 0], ...]
>
> or replace the entire tuple with a new one:
>
> >>> name, value = attributes[attribute_index]
> >>> attributes[attribute_index] = name, value + 42
> >>> attributes
> [('strength', 0), ('health', 42), ('wisdom', 0), ('dexterity', 0)]
>
> However, I think the pythonic way is to use a dictionary. If you want the
> user to input numbers you need a second dictionary to translate the numbers
> into attribute names:
>
> >>> attributes = dict(attributes)
> >>> lookup = {1: "strength", 2: "health", 3: "wisdom", 4: "dexterity"}
> >>> while True:
> ... index = input("index ")
> ... if not index: break
> ... amount = int(input("amount "))
> ... name = lookup[int(index)]
> ... attributes[name] += amount
> ...
> index 1
> amount 10
> index 2
> amount 20
> index 3
> amount 10
> index 2
> amount -100
> index
> >>> attributes
> {'dexterity': 0, 'strength': 10, 'health': -38, 'wisdom': 10}
>
> Personally I would ask for attribute names directly.
>
> ___
> Tutor maillist - Tutor@python.org
> To unsubscribe or change subscription options:
> http://mail.python.org/mailman/listinfo/tutor
>
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Re: [Tutor] Indexing a list with nested tuples
On 8/2/2011 11:39 PM, Alexander Quest wrote:
Hey Bob- thanks for the reply. Here is a more complete part of that
code section (the ellipses are parts where I've deleted code because I
don't think it's important for this question):
Please always reply-all so a copy goes to the list.
Thanks for posting more code & traceback
I forgot to mention earlier - tell us which version of Python you are
using (this looks like version 3)
You did not answer all my questions! How come? Please do so now.
_
attributes = [("strength", 0), ("health ", 0), ("wisdom ", 0),
("dexterity", 0)]
.
.
.
print(
"""
1 - Strength
2 - Health
3 - Wisdom
4 - Dexterity
Any other key - Quit
"""
)
selection = input("Selection: ")
if selection == "1" or selection == "2" or selection == "3" or
selection == "4":
print("You have ", points, "points available.")
how_many = input("How many would you like to add to
this attribute?: ")
while how_many < 0 or how_many > 30 or how_many ==
"": # Because max points available is
30, and entering less than 0 does not make sense.
print("Invalid entry. You have ", points, "points
available.") # If the user enters a
number less than 0, greater than 30, or just presses enter, it loops.
how_many = input("How many would you like to add
to this attribute?: ")
print("Added ", points, "to ",
attributes[selection-1][0], "attribute.") #
Here is where I try to add the number of points to the value, based on
what the user entered.
points = points -
how_many
# I subtract the number of points added from the total points available.
attributes[selection-1][1] +=
how_many
# I add the number of points the user selected to the variable selected.
__
Here's the traceback I get:
Traceback (most recent call last):
File "C:\Users\Alexander\Desktop\Python Practice\Ch05-2.py", line
54, in
print("Added ", points, "to ", attributes[selection-1][0],
"attribute.")
TypeError: unsupported operand type(s) for -: 'str' and 'int'
_
Thanks for any help. I understand that I can't change tuples directly,
but is there a way to change them indirectly (like saying
attribute.remove[x] and then saying attribute.append[x] with the new
variable? But this seems to take out both the string and the value,
when I only want to increase or decrease the value for one of the 4
strings, strength, health, wisdom, or dexterity).
DON'T USE TUPLES. WHY DO YOU INSIST ON THEM?
What does the error message( unsupported operand type(s) for -:
'str' and 'int') tell you?
Why would selection be a string rather than an integer?
This has to do with how you obtain selection from the user.
Why did you expect to be able to alter the value of a tuple
element? Tuples are immutable! Use a list instead.
--
Bob Gailer
919-636-4239
Chapel Hill NC
___
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Re: [Tutor] Indexing a list with nested tuples
Alexander Quest wrote:
> Hi guys- I'm having a problem with a list that has nested tuples:
>
> attributes = [("strength", 0), ("health ", 0), ("wisdom ", 0),
> ("dexterity", 0)]
>
> I've defined the list above with 4 items, each starting with a value of 0.
> The player
> enters how many points he or she wants to add to a given item. The
> selection menu
> is 1 - strength; 2 - health; 3 - wisdom; 4- dexterity. So the "selection"
> variable is actually
> 1 more than the index location of the intended item. So I have the
> following code:
>
> print("Added ", points, "to ", attributes[selection-1][0], "attribute.")
>
> My intent with this is to say that I've added this many points (however
> many) to the
> corresponding item in the list. So if the player selects "1", then
> selection = 1, but I subtract
> 1 from that (selection -1) to get the index value of that item in the list
> (in this case 0). Then I
> have [0] to indicate that I want to go to the second value within that
> first item, which is the
> point value. I get an error saying that list indices must be integers, not
> strings. I get a similar
> error even if I just put attributes[selection][0] without the minus 1.
>
> Also, it seems that the tuple within the list cannot be modified directly,
> so I can't add points to the original value of "0" that all 4 items start
> with. Is there a way to keep this nested list with
> tuples but be able to modify the point count for each item, or will it be
> better to create a dictionary or 2 separate lists (1 for the names
> "Strength, Health, Wisdom, Dexterity" and one
> for their starting values "0,0,0,0")? Any suggestions/help will be greatly
> appreciated!!!
[I'm assuming you are using Python 3. If not replace input() with
raw_input()]
Let's investigate what happens when you enter an attribute index:
>>> attribute_index = input("Choose attribute ")
Choose attribute 2
>>> attribute_index
'2'
Do you note the '...' around the number?
>>> attribute_index -= 1
Traceback (most recent call last):
File "", line 1, in
TypeError: unsupported operand type(s) for -=: 'str' and 'int'
It's actually a string, not an integer; therefore you have to convert it to
an integer before you can do any math with it:
>>> attribute_index = int(attribute_index)
>>> attribute_index
2
>>> attribute_index -= 1
>>> attribute_index
1
Now let's try to change the second tuple:
>>> attributes = [
... ("strength", 0), ("health", 0), ("wisdom", 0), ("dexterity", 0)]
>>> attributes[attribute_index]
('health', 0)
>>> attributes[attribute_index][1] += 42
Traceback (most recent call last):
File "", line 1, in
TypeError: 'tuple' object does not support item assignment
The error message is pretty clear, you cannot replace items of a tuple.
You can either to switch to nested lists
[["strength", 0], ["health", 0], ...]
or replace the entire tuple with a new one:
>>> name, value = attributes[attribute_index]
>>> attributes[attribute_index] = name, value + 42
>>> attributes
[('strength', 0), ('health', 42), ('wisdom', 0), ('dexterity', 0)]
However, I think the pythonic way is to use a dictionary. If you want the
user to input numbers you need a second dictionary to translate the numbers
into attribute names:
>>> attributes = dict(attributes)
>>> lookup = {1: "strength", 2: "health", 3: "wisdom", 4: "dexterity"}
>>> while True:
... index = input("index ")
... if not index: break
... amount = int(input("amount "))
... name = lookup[int(index)]
... attributes[name] += amount
...
index 1
amount 10
index 2
amount 20
index 3
amount 10
index 2
amount -100
index
>>> attributes
{'dexterity': 0, 'strength': 10, 'health': -38, 'wisdom': 10}
Personally I would ask for attribute names directly.
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Re: [Tutor] Indexing a list with nested tuples
On 8/2/2011 10:44 PM, Alexander Quest wrote:
Hi guys- I'm having a problem with a list that has nested tuples:
attributes = [("strength", 0), ("health ", 0), ("wisdom ", 0),
("dexterity", 0)]
I've defined the list above with 4 items, each starting with a value
of 0. The player
enters how many points he or she wants to add to a given item. The
selection menu
is 1 - strength; 2 - health; 3 - wisdom; 4- dexterity. So the
"selection" variable is actually
1 more than the index location of the intended item. So I have the
following code:
print("Added ", points, "to ", attributes[selection-1][0], "attribute.")
My intent with this is to say that I've added this many points
(however many) to the
corresponding item in the list. So if the player selects "1", then
selection = 1, but I subtract
1 from that (selection -1) to get the index value of that item in the
list (in this case 0). Then I
have [0] to indicate that I want to go to the second value within that
first item, which is the
point value. I get an error saying that list indices must be integers,
not strings. I get a similar
error even if I just put attributes[selection][0] without the minus 1.
Also, it seems that the tuple within the list cannot be modified
directly, so I can't add points to the original value of "0" that all
4 items start with. Is there a way to keep this nested list with
tuples but be able to modify the point count for each item, or will it
be better to create a dictionary or 2 separate lists (1 for the names
"Strength, Health, Wisdom, Dexterity" and one
for their starting values "0,0,0,0")? Any suggestions/help will be
greatly appreciated!!!
Thanks for inquiring. Some guidelines about questions:
1 - show us more code. in this case specifically how you obtain user input.
2 - show the complete traceback
What does the error message tell you? Why would selection be a string
rather than an integer? This has to do with how you obtain selection
from the user. What
Why did you expect to be able to alter the value of a tuple element?
Tuples are immutable! Use a list instead.
HTH
--
Bob Gailer
919-636-4239
Chapel Hill NC
___
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[Tutor] Indexing a list with nested tuples
Hi guys- I'm having a problem with a list that has nested tuples:
attributes = [("strength", 0), ("health ", 0), ("wisdom ", 0),
("dexterity", 0)]
I've defined the list above with 4 items, each starting with a value of 0.
The player
enters how many points he or she wants to add to a given item. The selection
menu
is 1 - strength; 2 - health; 3 - wisdom; 4- dexterity. So the "selection"
variable is actually
1 more than the index location of the intended item. So I have the following
code:
print("Added ", points, "to ", attributes[selection-1][0], "attribute.")
My intent with this is to say that I've added this many points (however
many) to the
corresponding item in the list. So if the player selects "1", then selection
= 1, but I subtract
1 from that (selection -1) to get the index value of that item in the list
(in this case 0). Then I
have [0] to indicate that I want to go to the second value within that first
item, which is the
point value. I get an error saying that list indices must be integers, not
strings. I get a similar
error even if I just put attributes[selection][0] without the minus 1.
Also, it seems that the tuple within the list cannot be modified directly,
so I can't add points to the original value of "0" that all 4 items start
with. Is there a way to keep this nested list with
tuples but be able to modify the point count for each item, or will it be
better to create a dictionary or 2 separate lists (1 for the names
"Strength, Health, Wisdom, Dexterity" and one
for their starting values "0,0,0,0")? Any suggestions/help will be greatly
appreciated!!!
-Alex
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Re: [Tutor] Indexing a List of Strings
Agreed that your original sequences are 1000 char long. But it helps to understand the problem better if you can give examples with smaller strings. Please can you post smaller examples? This will also help you test your code on your own inputs. On Wed, May 18, 2011 at 5:40 AM, Spyros Charonis wrote: > Greetings Python List, > > I have a motif sequence (a list of characters e.g. 'EAWLGHEYLHAMKGLLC') > whose index I would like to return. > The list contains 20 strings, each of which is close to 1000 characters > long making it far too cumbersome to display an example. > I would like to know if there is a way to return a pair of indices, one > index where my sequence begins (at 'E' in the above case) and > one index where my sequence ends (at 'C' in the above case). In short, if > 'EAWLGHEYLHAMKGLLC' spans 17 characters is it possible > to get something like 100 117, assuming it begins at 100th position and > goes up until 117th character of my string. My loop goes as > follows: > > for item in finalmotifs: > for line in my_list: > if item in line: > print line.index(item) > > But this only returns a single number (e.g 119), which is the index at > which my sequence begins. > > Is it possible to get a pair of indices that indicate beginning and end of > substring? > > Many thanks > > > > ___ > Tutor maillist - Tutor@python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor > > -- http://spawgi.wordpress.com We can do it and do it better. ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Indexing a List of Strings
"Spyros Charonis" wrote for item in finalmotifs: for line in my_list: if item in line: print line.index(item) But this only returns a single number (e.g 119), which is the index at which my sequence begins. Is it possible to get a pair of indices that indicate beginning and end of substring? print line.index(item)+len(item) Presumably since its matching item the end index will be len(item) characters later? Or am I missing something? Alan G. ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
[Tutor] Indexing a List of Strings
Greetings Python List, I have a motif sequence (a list of characters e.g. 'EAWLGHEYLHAMKGLLC') whose index I would like to return. The list contains 20 strings, each of which is close to 1000 characters long making it far too cumbersome to display an example. I would like to know if there is a way to return a pair of indices, one index where my sequence begins (at 'E' in the above case) and one index where my sequence ends (at 'C' in the above case). In short, if 'EAWLGHEYLHAMKGLLC' spans 17 characters is it possible to get something like 100 117, assuming it begins at 100th position and goes up until 117th character of my string. My loop goes as follows: for item in finalmotifs: for line in my_list: if item in line: print line.index(item) But this only returns a single number (e.g 119), which is the index at which my sequence begins. Is it possible to get a pair of indices that indicate beginning and end of substring? Many thanks ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
