Generate cut list for 2x4s in Fusion 360.

figure.py

#! /usr/local/bin/python3

# assumes the the BOM has been generated from https://github.com/macmanpb/CSV-BOM
# in 360: install plugin, "create" menu > create BOM, defaults should be fine

import csv
import argparse

boards = []

parser = argparse.ArgumentParser(description='Find cuts to make in boards based on given dimensions')
parser.add_argument('file', type=str, help='file from which to read board lengths')
parser.add_argument('length', type=int, help='length of board you will buy (inches)')
parser.add_argument('--outfile', type=str, help='CSV file to write cuts to, if desired')

args = parser.parse_args()

BOARD_LENGTH = args.length # inches

with open(args.file) as f:
    reader = csv.reader(f)

    next(reader)

    for row in reader:
        name = row[0]
        dims = sorted([ float(i) for i in row[2:5] ])
        
        if dims[0] == 1.5 and dims[1] == 3.5:
            print("counting", name, dims)

            boards.append((name, dims[2], dims))
        else:
            print("skipping", name, dims)

placed_boards = []

sorted_boards = sorted(boards, key=lambda b: b[1], reverse=True)

left = BOARD_LENGTH
cuts = []

leftover = 0

while len(sorted_boards) != 0:
    found = False  # have we found a size that will fit in what's left of the current board?

    for i, b in enumerate(sorted_boards):
        if b[1] <= left:
            # look through all the sizes until we find one sufficiently short
            # then chop it off the current board
            cuts.append(b[0:2])
            left -= b[1]
            sorted_boards.pop(i)
            print("popping", b)
            found = True
            break

    if not found or len(sorted_boards) == 0:
        print("NEW BOARD")
        # when there are no more sizes that fit, start with a new board
        leftover += left
        placed_boards.append(cuts)
        cuts = []
        left = BOARD_LENGTH


for i, p in enumerate(placed_boards):
    print("BOARD", i+1)
    for cuts in p:
        print("\t{}\" ({})".format(cuts[1], cuts[0]))

if args.outfile:
    print("\nwriting cuts to {}".format(args.outfile))
    with open("cuts.csv", 'w', newline='') as w:
        writer = csv.writer(w)
        for i, p in enumerate(placed_boards):
            for cuts in p:
                writer.writerow([i+1, cuts[1], cuts[0]])

print()

print("utilization: {0:.1f}%".format((100 - leftover / (BOARD_LENGTH * len(placed_boards)) * 100)))
print("wasted board: {}\"".format(leftover))
print("{}\" boards required: {}".format(BOARD_LENGTH, len(placed_boards)))