RS(1)RS(1)NAMErs - reshape a data array
SYNOPSISrs [ -[csCS][x][kKgGw][N]tTeEnyjhHm ] [ rows [ cols ] ]
DESCRIPTION
Rs reads the standard input, interpreting each line as a
row of blank-separated entries in an array, transforms the
array according to the options, and writes it on the stan-
dard output. With no arguments it transforms stream input
into a columnar format convenient for terminal viewing.
The shape of the input array is deduced from the number of
lines and the number of columns on the first line. If
that shape is inconvenient, a more useful one might be
obtained by skipping some of the input with the -k option.
Other options control interpretation of the input columns.
The shape of the output array is influenced by the rows
and cols specifications, which should be positive inte-
gers. If only one of them is a positive integer, rs com-
putes a value for the other which will accommodate all of
the data. When necessary, missing data are supplied in a
manner specified by the options and surplus data are
deleted. There are options to control presentation of the
output columns, including transposition of the rows and
columns.
The options are described below.
-cx Input columns are delimited by the single character
x. A missing x is taken to be `^I'.
-sx Like -c, but maximal strings of x are delimiters.
-Cx Output columns are delimited by the single charac-
ter x. A missing x is taken to be `^I'.
-Sx Like -C, but padded strings of x are delimiters.
-t Fill in the rows of the output array using the
columns of the input array, that is, transpose the
input while honoring any rows and cols specifica-
tions.
-T Print the pure transpose of the input, ignoring any
rows or cols specification.
-kN Ignore the first N lines of input.
-KN Like -k, but print the ignored lines.
-gN The gutter width (inter-column space), normally 2,
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is taken to be N.
-GN The gutter width has N percent of the maximum col-
umn width added to it.
-e Consider each line of input as an array entry.
-n On lines having fewer entries than the first line,
use null entries to pad out the line. Normally,
missing entries are taken from the next line of
input.
-y If there are too few entries to make up the output
dimensions, pad the output by recycling the input
from the beginning. Normally, the output is padded
with blanks.
-h Print the shape of the input array and do nothing
else. The shape is just the number of lines and
the number of entries on the first line.
-H Like -h, but also print the length of each line.
-j Right adjust entries within columns.
-wN The width of the display, normally 80, is taken to
be the positive integer N.
-m Do not trim excess delimiters from the ends of the
output array.
With no arguments, rs transposes its input, and assumes
one array entry per input line unless the first non-
ignored line is longer than the display width. Option
letters which take numerical arguments interpret a missing
number as zero unless otherwise indicated.
EXAMPLES
Rs can be used as a filter to convert the stream output of
certain programs (e.g., spell, du, file, look, nm, who,
and wc(1)) into a convenient ``window'' format, as in
who | rs
This function has been incorporated into the ls(1) pro-
gram, though for most programs with similar output rs suf-
fices.
To convert stream input into vector output and back again,
use
rs 1 0 | rs 0 1
A 10 by 10 array of random numbers from 1 to 100 and its
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transpose can be generated with
jot -r 100 | rs 10 10 | tee array
| rs-T > tarray
In the editor vi(1), a file consisting of a multi-line
vector with 9 elements per line can undergo insertions and
deletions, and then be neatly reshaped into 9 columns with
:1,$!rs 0 9
Finally, to sort a database by the first line of each
4-line field, try
rs-eC 0 4 | sort | rs-c 0 1
SEE ALSOjot(1), vi(1), sort(1), pr(1)BUGS
Handles only two dimensional arrays.
The algorithm currently reads the whole file into memory,
so files that do not fit in memory will not be reshaped.
Fields cannot be defined yet on character positions.
Re-ordering of columns is not yet possible.
There are too many options.
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