mirror of
https://github.com/nushell/nushell.git
synced 2024-11-22 16:33:37 +01:00
7a77910720
There are many use cases. Here we introduce the following: - The rows can be rolled `... | roll` (up) or `... | roll down` - Columns can be rolled too (the default is on the `left`, you can pass `... | roll column --opposite` to roll in the other direction) - You can `roll` the cells of a table and keeping the header names in the same order (`... | roll column --cells-only`) - Above examples can also be passed (Ex. `... | roll down 3`) a number to tell how many places to roll. Basic working example with rolling columns: ``` > echo '00000100' | split chars | each { str to-int } | rotate counter-clockwise _ | reject _ | rename bit1 bit2 bit3 bit4 bit5 bit6 bit7 bit8 ───┬──────┬──────┬──────┬──────┬──────┬──────┬──────┬────── # │ bit1 │ bit2 │ bit3 │ bit4 │ bit5 │ bit6 │ bit7 │ bit8 ───┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼────── 0 │ 0 │ 0 │ 0 │ 0 │ 0 │ 1 │ 0 │ 0 ───┴──────┴──────┴──────┴──────┴──────┴──────┴──────┴────── ``` We want to "shift" three bits to the left of the bitstring (four in decimal), let's try it: ``` > echo '00000100' | split chars | each { str to-int } | rotate counter-clockwise _ | reject _ | rename bit1 bit2 bit3 bit4 bit5 bit6 bit7 bit8 | roll column 3 ───┬──────┬──────┬──────┬──────┬──────┬──────┬──────┬────── # │ bit4 │ bit5 │ bit6 │ bit7 │ bit8 │ bit1 │ bit2 │ bit3 ───┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼────── 0 │ 0 │ 0 │ 1 │ 0 │ 0 │ 0 │ 0 │ 0 ───┴──────┴──────┴──────┴──────┴──────┴──────┴──────┴────── ``` The tables was rolled correctly (32 in decimal, for above bitstring). However, the *last three header names* look confusing. We can roll the cell contents only to fix it. ``` > echo '00000100' | split chars | each { str to-int } | rotate counter-clockwise _ | reject _ | rename bit1 bit2 bit3 bit4 bit5 bit6 bit7 bit8 | roll column 3 --cells-only ───┬──────┬──────┬──────┬──────┬──────┬──────┬──────┬────── # │ bit1 │ bit2 │ bit3 │ bit4 │ bit5 │ bit6 │ bit7 │ bit8 ───┼──────┼──────┼──────┼──────┼──────┼──────┼──────┼────── 0 │ 0 │ 0 │ 1 │ 0 │ 0 │ 0 │ 0 │ 0 ───┴──────┴──────┴──────┴──────┴──────┴──────┴──────┴────── ``` There we go. Let's compute it's decimal value now (should be 32) ``` > echo '00000100' | split chars | each { str to-int } | rotate counter-clockwise _ | reject _ | roll column 3 --cells-only | pivot bit --ignore-titles | get bit | reverse | each --numbered { = $it.item * (2 ** $it.index) } | math sum 32 ``` |
||
---|---|---|
.. | ||
commands | ||
format_conversions | ||
main.rs |