Gamma PDF Value

Problem

Gamma probability density with shape and rate parameters at x:

f(x) = rate^shape * x^(shape - 1) * e^(-rate * x) / Gamma(shape).

Return 0.0 for nonpositive parameters or x <= 0.

Hint

math.gamma(shape) is the normalizing constant.

case 1

in: [1,1,1]

expected: 0.36787944117144233

case 2

in: [2,1,2]

expected: 0.2706705664732254

case 3

in: [3,2,1]

expected: 0.5413411329464508

case 4

in: [1,1,-1]

expected: 0

Starter codePython

import math


def gamma_pdf_value(shape, rate, x):
    # Your code here
    pass

4 test cases · run your code against them in the editor