How to get the numeric value of an integral using sympy?-CodePudding

I'm trying to use this function

def mean(f):
    r=sym.integrate(f,(t,0,0.02))
    return r

where f is

    f1=t
    x=t
    x=sym.sin(2*pi*50*t)
    f1=sym.sign(x)

And t is:

t=Symbol('t')

When I run the program I get this:

Integral(Piecewise((1, sin(314.159265358979*t) > 0), (-1, sin(314.159265358979*t) < 0), (0, True)), (t, 0, 0.02))

Is there a way to get the numeric answer?

CodePudding user response：

That's happening because you are using pi from a numerical package (I guess math or numpy). When using symbolic expressions, you should use pi exposed by Sympy.

import sympy as sym

def mean(f):
    r=sym.integrate(f,(t,0,0.02))
    return r

t=Symbol('t')
x=sym.sin(2*sym.pi*50*t)
f1=sym.sign(x)
mean(f1)
# output: 0