Python Can Python handle numeric integration with exponential functions?

AI Thread Summary
The discussion revolves around writing a Python program to numerically evaluate the function y(t) = exp(Integrate[A(x), x]) from 0 to t. The user initially attempted to use the quad function from scipy.integrate but found it inadequate for this specific form. Clarification was sought on the expression, confirming that the goal is to compute y(t) = exp(∫_0^t A(x) dx) for a specific function A(x). It was noted that while quad can evaluate integrals, it does so for one value of t at a time. A solution was proposed, demonstrating how to define a function that utilizes quad within another function to compute y(t) effectively. The example provided illustrates how to define both the integrand and the function y(t), allowing for numerical evaluation across different values of t.
sola maths
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I'm trying to write a python program that is able to numerically execute functions of the form:

y(t) = exp(Integrate[A(x),x]) within the bounds of 0 and t

I tried using quad from scipy.integrate but it seems not to be able to evaluate expressions of this form.

Any other suggestions on appropriate packages or commands?
 
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sola maths said:
I'm trying to write a python program that is able to numerically execute functions of the form:

y(t) = exp(Integrate[A(x),x]) within the bounds of 0 and t

I tried using quad from scipy.integrate but it seems not to be able to evaluate expressions of this form.

Any other suggestions on appropriate packages or commands?

Can you be a bit more specific sola maths? Do you mean:

y(t) = \exp(\int_0^t A(x) \, dx)

You have some specific function A(x) that you can evaluate numerically?

Also, is that just you integrand? Do you need to evaluate,

\int_a^b \, e^{\int_0^t A(x) \, dx} \, dt
 
Hi uart,

Yes, I have some function A(x) that I need to evaluate numerically as x changes. The first expression you wrote is what I meant.
 
sola maths said:
Hi uart,

Yes, I have some function A(x) that I need to evaluate numerically as x changes. The first expression you wrote is what I meant.

Ok so it's just y(t) = \exp(\int_0^t A(x) \, dx) that you need to evaluate.

Quad can do this easily, but only for one particular value of "t" at a time. However you could call it (quad) from within a function if you wished to properly make a function of "t". For example,

Code:
def functA(x):
     return x*x/2.0

def functY(t):
     return exp(integrate.quad(functA,0,t)[0])

functY(3)
90.017131300521896
 
Your explanation makes lots of sense...

I'd defined a function but had difficulty making it a function of t... Thanks.
 
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