Oh, thanks a lot. Now it's working fine.
Now the only problem is that the code is evaluated when calling
sympify, and not when calling evalf.
Could I ask you what is the way to keep the function lazy? I explain
myself better. Since the function SUM has to operate on a database if
I have something l
Yes, that worked. But I had to restructure the code
class SUM(Function):
nargs = 2
@classmethod
def eval(cls, arg):
cls.arg=arg
@classmethod
def _eval_evalf(cls, arg):
map = Code("""function () {
emit("sum",{%(field)s:this.%(field)s});
Actually you're wrong. Every instance of a class in python has its own
attributes and editing the attributes of one instance of a class wont
modify the attributes of the other classes.
Try:
class MyClass:
def __init__(self,var):
self.var=var
then execute:
>>> a = MyClass(10)
>>> pri
WAIT, I didn't see that you use
self.arg[0]!! that's why my code was giving me 57, I just need to call
cls.arg[0], great now I can remove the eval ;)! thanks again
On Jun 2, 9:30 pm, luke wrote:
> Actually you're wrong. Every instance of a class in python has its own
> attributes and editing the
Nope in spite of my enthusiasm cls.args wont work properly as it will
give me a and not a :) I'll put back my eval since
it worked. Hope that was of any help!
On Jun 2, 9:32 pm, luke wrote:
> WAIT, I didn't see that you use
> self.arg[0]!! that's why my code was giving me 57, I just need to ca
My bad, sorry for my inexperience with sympy, final code: (this is
really working!)
class SUM(Function):
nargs = 1
def _eval_evalf(cls, prec):
print cls.args
map = Code("""function () {
emit("sum",{%(field)s:this.%(field)s});
}"""
Le jeudi 02 juin 2011 à 08:03 -0700, luke a écrit :
> Oh, thanks a lot. Now it's working fine.
> Now the only problem is that the code is evaluated when calling
> sympify, and not when calling evalf.
> Could I ask you what is the way to keep the function lazy? I explain
> myself better. Since the f
Le jeudi 02 juin 2011 à 09:35 -0700, luke a écrit :
> Yes, that worked. But I had to restructure the code
>
> class SUM(Function):
> nargs = 2
> @classmethod
> def eval(cls, arg):
> cls.arg=arg
> @classmethod
> def _eval_evalf(cls, arg):
> map = Code("""function
This is indeed a very interesting application of SymPy. Here we see one
example of the power of symbolic computer algebra systems, which is that
symbolic preprocessing, even very simple preprocessing like what we have here,
can greatly optimize arbitrary code execution.
If your expressions a
Is there a specific reason why you want to use evalf() to do your lookups, or
is it just because you want something that will recurse down the expression
tree?
Aaron Meurer
On Jun 2, 2011, at 2:10 PM, luke wrote:
> My bad, sorry for my inexperience with sympy, final code: (this is
> really w
10 matches
Mail list logo
