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Math Documentation (#1982 )

* Adding math docs

* Add some comments to calculate

* Remove redudant message

Message already shows up in subcommands list

* Added not working example

Accidentantly

* Remove table

2020-06-15 08:42:15 +12:00

4.2 KiB

Raw Blame History

math

Mathematical functions that generally only operate on a list of numbers (integers, decimals, bytes) and tables. Currently the following functions are implemented: math average Get the average of a list of number math min Get the minimum of a list of numbers math max Get the maximum of a list of numbers

However, the mathematical functions like min and max are more permissive and also work on Dates.

Examples

To get the average of the file sizes in a directory, simply pipe the size column from the ls command to the average command.

List of Numbers (Integers, Decimals, Bytes)

> ls
 #  │ name               │ type │ size     │ modified 
────┼────────────────────┼──────┼──────────┼─────────────
  0 │ CODE_OF_CONDUCT.md │ File │   3.4 KB │ 4 days ago 
  1 │ CONTRIBUTING.md    │ File │   1.3 KB │ 4 days ago 
  2 │ Cargo.lock         │ File │ 106.3 KB │ 6 mins ago 
  3 │ Cargo.toml         │ File │   4.6 KB │ 3 days ago 
  4 │ LICENSE            │ File │   1.1 KB │ 4 days ago 
  5 │ Makefile.toml      │ File │    449 B │ 4 days ago 
  6 │ README.md          │ File │  16.0 KB │ 6 mins ago 
  7 │ TODO.md            │ File │      0 B │ 6 mins ago 
  8 │ assets             │ Dir  │    128 B │ 4 days ago 
  9 │ build.rs           │ File │     78 B │ 4 days ago 
 10 │ crates             │ Dir  │    672 B │ 3 days ago 
 11 │ debian             │ Dir  │    352 B │ 4 days ago 
 12 │ docker             │ Dir  │    288 B │ 4 days ago 
 13 │ docs               │ Dir  │    160 B │ 4 days ago 
 14 │ features.toml      │ File │    632 B │ 4 days ago 
 15 │ images             │ Dir  │    160 B │ 4 days ago 
 16 │ justfile           │ File │    234 B │ 3 days ago 
 17 │ rustfmt.toml       │ File │     16 B │ 4 days ago 
 18 │ src                │ Dir  │    128 B │ 4 days ago 
 19 │ target             │ Dir  │    192 B │ 8 hours ago 
 20 │ tests              │ Dir  │    192 B │ 4 days ago 

> ls | get size | math average
───┬────────
 0 │ 6.5 KB 
───┴────────

> ls | get size | math min
───┬─────
 0 │ 0 B 
───┴─────
> ls | get size | math max
───┬──────────
 0 │ 106.3 KB 
───┴──────────

# Dates
> ls | get modified | math min
2020-06-09 17:25:51.798743222 UTC

> ls | get modified | math max
2020-06-14 05:49:59.637449186 UT

Operations on tables

>  pwd | split row / | size 
───┬───────┬───────┬───────┬────────────
 # │ lines │ words │ chars │ max length 
───┼───────┼───────┼───────┼────────────
 0 │     0 │     1 │     5 │          5 
 1 │     0 │     1 │     7 │          7 
 2 │     0 │     1 │     9 │          9 
 3 │     0 │     1 │     7 │          7 
───┴───────┴───────┴───────┴────────────

> pwd | split row / | size | math max
───────────┬───
 lines      │ 0 
 words      │ 1 
 chars      │ 9 
 max length │ 9 
────────────┴───

> pwd | split row / | size | math average
────────────┬────────
 lines      │ 0.0000 
 words      │ 1.0000 
 chars      │ 7.0000 
 max length │ 7.0000 
────────────┴────────

Errors

math functions are aggregation functions so empty lists are invalid

> echo [] | math average
error: Error: Unexpected: Cannot perform aggregate math operation on empty data

Note math functions only work on list of numbers (integers, decimals, bytes) and tables of numbers, if any other types are piped into the function then unexpected results can occur.

>  echo [1 2 a ] | math average
0

4.2 KiB Raw Blame History