Jacob Rael wrote:
> Hello,
>
> I would like write a function that I can pass an expression and a
> dictionary with values. The function would return a function that
> evaluates the expression on an input. For example:
>
> fun = genFun("A*x+off", {'A': 3.0, 'off': -0.5, 'Max': 2.0, 'Min':
> -2.0} )
>
>>>> fun(0)
> -0.5
>>>> fun(-10)
> -2
>>>> fun(10)
> 2
>
> so fun would act as if I did:
>
> def fun(x):
> A = 3
> off = -0.5
> Max = 2
> Min = -2
> y = min(Max,max(Min,A*x + off))
> return(y)
>
> Any ideas?
>
> jr
>
You might prefer to write your expression as a real function, rather than a
source string, so that it would be easier to test.
>>> def fun(x, A, off, Max, Min):
... return min(Max,max(Min,A*x + off))
...
Then you can "curry" in the constant values, using something like:
>>> def getFun(fn, env_dict):
... env_dict = env_dict.copy()
... def fun_curry(x):
... return fn(x,**env_dict)
... return fun_curry
...
>>> myenv = {'A': 3.0, 'off': -0.5, 'Max': 2.0, 'Min': -2.0}
>>> fun1 = getFun(fun, myenv)
>>> fun1(0)
-0.5
>>> fun1(0.5)
1.0
>>> fun1(-10)
-2.0
>>> fun1(10)
2.0
HTH
Michael
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