MediumCalculusca-253

Directional Derivative in 3D

Problem

The directional derivative of a differentiable function f at a point in the direction v is the gradient dotted with the unit vector v / ||v||.

Given the gradient components as the list g and the direction as the list v with ||v|| > 0, return that scalar.

Hint

The direction must be normalized before taking the dot product with the gradient.

case 1

in: [[1,2,3],[1,0,0]]

expected: 1

case 2

in: [[1,1,1],[1,1,1]]

expected: 1.7320508075688774

case 3

in: [[2,0,-1],[0,0,5]]

expected: -1

case 4

in: [[1,2,2],[2,-1,2]]

expected: 1.3333333333333333

Starter codePython

def directional_derivative_3d(g, v):
    # Your code here
    pass

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