What is the binpacking problem?

Let's explain! The binpacking problem is a problem in which there are a random size item and multiple bins of the same size to pack it, and the number of bins is minimized.

English wiki

1D binpacking problem

There is oneDpack. with anaconda prompt

pip install oneDpack

How to use Enter the size of bin as cap and the size of what you want to put in items. Larger caps are very slow.

from oneDpack import*

cap=60
items=[2,4,5,2,7,4,7,3,7,3,7,43,8,2,4,13,6,4,3,2,4,7,9,10,40,23]
for i in packing(cap,items):
    print(i)
    print(sum(i))

output

[4, 13, 43]
60
[2, 3, 4, 4, 7, 40]
60
[2, 2, 3, 3, 4, 7, 7, 7, 7, 8, 10]
60
[2, 4, 5, 6, 9, 23]
49

2D binpacking problem

There is a reckpack. with anaconda prompt

pip install reckpack

How to use Enter the size of bins and the vertical and horizontal sizes of cargo.

import matplotlib.pyplot as plt
from matplotlib.patches import Rectangle
from collections import*
from rectpack import newPacker
from pandas import*
from numpy import*

bins = [(50,50)]
cargo = [(15,20),(30,20),(15,20),(10,20),(20,14),(15,20),(11,20),(30,10)]

packer = newPacker()

#Set the container.
for i, b in enumerate(bins):
    packer.add_bin(*b, bid=i)

#Set the box.
for i, r in enumerate(cargo):
    packer.add_rect(*r, rid=i)

#Perform mass filling.
packer.pack()


for i, abin in enumerate(packer,1):
    for r in abin:
        print(r.x,r.y,r.width, r.height)

output

Outputs the x-coordinate from the lower left, the y-coordinate from the lower left, the length from left to right, and the length from bottom to top.

0 0 30 20
30 0 20 15
30 15 20 15
0 30 15 20
0 20 30 10
15 30 14 20
29 30 11 20
40 30 10 20

It will be like this when visualized.

%matplotlib inline

def draw_result(packer):
    #Screen size
    fig = plt.figure(figsize=(20,10))
    for i, abin in enumerate(packer,1):
        ax = fig.add_subplot(i, len(packer), 1, aspect="equal")
        
        #Draw the container.
        ax.add_patch(Rectangle((0,0), abin.width, abin.height, fc="none", ec="g", lw=2, zorder=10))
        for r in abin:
            #Draw a box.
            ax.add_patch(Rectangle((r.x, r.y), r.width, r.height, fc="lightblue", ec="k"))
            cx, cy = r.x + r.width / 2, r.y + r.height / 2
            ax.text(cx, cy, r.rid, ha ="center",va="center", color="k", fontsize=14)
        
        ax.relim()
        ax.autoscale_view()

draw_result(packer)

ダウンロード.png

3D binpacking problem

We are currently searching, please let us know in the comments if you have any recommendations.

Recommendation of binpacking library of python

What is the binpacking problem?

1D binpacking problem

2D binpacking problem

3D binpacking problem