debugger_ref.py

def what(x):
    # jibberish
    add = x+x
    new = add -1
    n2 = new * new
    div = n2/2
    import pdb; pdb.set_trace()
    return div

def binary_search(array, val):
    # simple binary search implementation
    import pdb; pdb.set_trace()
    arr = array
    min_idx = 0
    max_idx = len(array)

    while min_idx < max_idx:
        middle_idx = (min_idx + max_idx) // 2

        if array[middle_idx] == val:
            return middle_idx
        elif array[middle_idx] < val:
            min_idx = middle_idx + 1
        else:
            max_idx = middle_idx
    return None

# test and debug binary search
x = [5, 4, 3, 6, 1]
binary_search([1,2,4,7,10,11], val=10)

'''
In pdb, set the following mythical commands
'''
# value --> prints variable
# s --> Execute the current line
# n --> Continue execution until the next line in the current function is reached or it returns.
# ll -> View the whole source code(function)
# l -> 11 lines around the set_trace() block
# r --> Continue execution until the current function returns. This let's you examine the final outcome of a function.
# c -> exit pdb debugger

• pdb-tutorial
• pdb-docs
• pdf-realpython
• https://docs.python.org/3/library/pdb.html#debugger-commands
• https://github.com/PyTorchLightning/engineering-class/blob/master/ep05-debugging/Ep05-ShowNotes.md

• l(ist) - Displays 11 lines around the current line or continue the previous listing.
• s(tep) - Execute the current line, stop at the first possible occasion.
• n(ext) - Continue execution until the next line in the current function is reached or it returns.
• b(reak) - Set a breakpoint (depending on the argument provided).
• r(eturn) - Continue execution until the current function returns.
• q - to quit
• h - for help

import pdb; pdb.set_trace()
import matplotlib.pyplot as plt
plt.imshow(img); plt.show()