[FIXED] Create numpy array with conditional step

Issue

Im trying to convert this code into one-liner function using lambda and numpy, the function should return numpy array, but i dont know how to save the step value for each iteration

import random

def generate_array(n: int):
    step = 1
    arr = []
    
    for i in range(n):
        step = step + 1 if random.choice([True, False]) else step - 1 
        arr .append(step)

    return arr

generate_array(10)

Solution

You can first create the difference array using np.random.choice, and then sum each item up cumulatively using np.cumsum():

np.cumsum(np.random.choice([1, -1], size=10))

Answered By - QuantumMecha