Sergey Dorofeev wrote:
> "Peter Otten" <[EMAIL PROTECTED]> wrote in message
> news:[EMAIL PROTECTED]
>> Sergey Dorofeev wrote:
>>
>>> Please help, is there way to use sub-expressions in lambda?
>>> For example, if I want to calculate sin(x^2)+cos(x^2) I must code:
>>> lambda x: sin(x*x)+cos(x*x)
>>> How to make x*x to be evaluated once?
>>
>>>>> (lambda x: [sin(x2) + cos(x2) for x2 in [x*x]][0])(.5) == sin(.5*.5) +
>> cos(.5*.5)
>> True
>>
>> The real answer is of course: Use a function.
>
> But what about something like
>
> lambda x: sin(y)+cos(y) where y=x*x
>
> ?
> May be this could be a PEP? If there is no straight way to do this.
def f(x):
y = x*x
return sin(y) + cos(y)
What is not straightforward about that?
Peter
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