Writing

Answering How Many with Software

How many? is a typical question that comes up when programming. I use a variety of software for projects and there are subtly different ways to answer that question depending on the context.

Here is an alphabetical list of ways I’ve recently answered that question. A more detailed comparison of programming languages can be found on Wikipedia.

Command Line

# How many rows are in this file?
wc -l < file

Golang

// How many elements are in this array?
len(array)

JavaScript

// How many elements are in this array?
array.length

// How many elements in this array are greater than 5?
d3.count(array, (d) => d > 5)

// How many rows are in this Apache Arrow table?
table.numRows

Liquid Tags in Jekyll

<!-- How many elements are in this array? -->
array | size

Python

# How many elements are in this list?
len(list)

# How many elements are in this pandas dataframe?
df.size # including missing values
df.count() # excluding missing values

# How many elements are in this numpy array?
ndarray.size

Ruby

# How many elements are in this array?
array.length
array.count
array.size

# How many rows are in this Active Record table?
table.count

SQL

-- How many elements are in this PostgreSQL array?
array_length(array, 1)

-- How many elements are in this DuckDB list?
len(list)

-- How many rows are in this table?
select count(*) from table

Terraform

# How many elements are in this list?
length(list)

Make Flickr shapes JSON parsable

Update: Flickr has released version 2.0.1 so this is no longer necessary. Thanks Flickr :D

Internal Type Juggling in PHP 5.2 vs PHP 5.3

There is an undocumented case where the output of an internal function is different in PHP 5.2 vs PHP 5.3 when you pass it an invalid argument.

Load-bearing Code

The term 'load-bearing code' can be used to refer to software that exhibits the following attributes.

Has no documentation or automated tests
Written by an ex-developer
Used by a large portion of the code base
Supports critical system processes

Jerry, these are load-bearing walls, they're not gonna come down!
Cosmo Kramer in the Seinfeld episode "The Chicken Roaster"

I have encountered load-bearing code in legacy open source applications, inherited projects, or debugging production software.

Calculating Different Mii Combinations

How many different Mii designs are possible? I started counting the options, did the math, and here are the results.

	Attribute	Options
1	Genders	2
2	Clothing Colors	12
3	Heights	10
4	Weights	10
5	Face Shapes	8
6	Makeup Types	12
7	Skin Colors	6
8	Hair Styles	72
9	Hair Parts	2
10	Hair Colors	8
11	Eyebrows	24
12	Eyebrow Colors	8
13	Eyebrow Vertical Steps	16
14	Eyebrow Size Steps	9
15	Eyebrow Rotation Steps	12
16	Eyebrow Horizontal Steps	13
17	Eye Types	42
18	Eye Colors	6
19	Eye Vertical Steps	19
20	Eye Size Steps	8
21	Eye Rotation Steps	8
22	Eye Horizontal Steps	13
23	Noses	12
24	Nose Vertical Steps	19
25	Nose Sizes	9
26	Lips	24
27	Lips Colors	3
28	Lips Vertical Steps	19
29	Lips Sizes	9
30	Glasses	9
31	Glasses Colors	6
32	Glasses Vertical Steps	21
33	Glasses Sizes	8
34	Mustaches	4
35	Mustache Colors	8
36	Mustache Vertical Steps	17
37	Mustache Sizes	9
38	Moles	2
39	Mole Vertical Steps	31
40	Mole Sizes	9
41	Mole Horizontal Steps	17
42	Goatee Types	4
43	Goatee Colors	8
	Total	568

Exceptions

1 hair style (bald) has no color or part
49 hair styles have no part
1 eyebrow style(none) has no color, vertical step, size, rotation or horizontal step
7 eye types have no color
17 lips have no color
1 glasses type (none) has no color, vertical step, or size
1 mustache type (none) has no color, vertical step, or size
1 mole (none) has no vertical step, size, or horizontal step
1 goatee type (none) has no color

Combinations

To determine the number of distinct combinations I used the formula: 568! / (43! * (568-43)!)

Result

Using Wolfram Alpha to solve 568! / (43! * (568-43)!), we can see that there are 88 vigintillion, 613 novemdecillion, 583 octodecillion, 674 septendecillion, 758 sexdecillion, 947 quindecillion, 813 quattuordecillion, 475 tredecillion, 143 duodecillion, 744 undecillion, 24 decillion, 970 nonillion, 165 octillion, 692 septillion, 788 sextillion, 754 quintillion, 421 quadrillion, 531 trillion, 161 billion, 395 million, 650 thousand and 32 Mii Combinations.