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5.5 KiB
math
Mathematical functions that generally only operate on a list of numbers (integers, decimals, bytes) and tables. Currently the following functions are implemented:
math avg: Finds the average of a list of numbers or tablesmath eval: Evaluates a list of math expressions into numbersmath max: Finds the maximum within a list of numbers or tablesmath median: Finds the median of a list of numbers or tablesmath min: Finds the minimum within a list of numbers or tablesmath mode: Finds the most frequent element(s) within a list of numbers or tablesmath stddev: Finds the standard deviation of a list of numbers or tablesmath sum: Finds the sum of a list of numbers or tablesmath product: Finds the product of a list of numbers or tablesmath variance: Finds the variance of a list of numbers or tables
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 avg
───┬────────
# │
───┼────────
0 │ 7.2 KB
───┴────────
> ls | get size | math min
───┬─────
# │
───┼─────
0 │ 0 B
───┴─────
> ls | get size | math max
───┬──────────
# │
───┼──────────
0 │ 113.6 KB
───┴──────────
> ls | get size | math median
───┬───────
# │
───┼───────
0 │ 320 B
───┴───────
> ls | get size | math sum
───┬──────────
# │
───┼──────────
0 │ 143.6 KB
───┴──────────
> echo [3 3 9 12 12 15] | math mode
───┬────
0 │ 3
1 │ 12
───┴────
> echo [2 3 3 4] | math product
72
> echo [1 4 6 10 50] | math stddev
18.1372
> echo [1 4 6 10 50] | math variance
328.96
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 │ bytes
───┼───────┼───────┼───────┼────────────
0 │ 0 │ 1 │ 5 │ 5
1 │ 0 │ 1 │ 11 │ 11
2 │ 0 │ 1 │ 11 │ 11
3 │ 0 │ 1 │ 4 │ 4
4 │ 0 │ 2 │ 12 │ 12
5 │ 0 │ 1 │ 7 │ 7
───┴───────┴───────┴───────┴────────────
> pwd | split row / | size | math max
────────────┬────
lines │ 0
words │ 2
chars │ 12
bytes │ 12
────────────┴────
> pwd | split row / | size | math avg
────────────┬────────
lines │ 0.0000
words │ 1.1666
chars │ 8.3333
bytes │ 8.3333
────────────┴────────
To get the sum of the characters that make up your present working directory.
> pwd | split row / | size | get chars | math sum
50
Errors
math functions are aggregation functions so empty lists are invalid
> echo [] | math avg
error: Error: Unexpected: Cannot perform aggregate math operation on empty data