out

Write output data to a named file or standard output.

Usage

gurita out [--sep STR] [--na STR] [-h] [FILE]

Arguments

Argument	Description	Reference
`-h` `--help`	display help for this command	help
`--sep STR`	Specify the field separator	sep
`[--na STR]`	Specify missing value marker	na marker
`[FILE]`	Optional output file name	file name

Simple example

Read the contents of iris.csv as an input CSV file and write the output to iris.tsv in TSV format

gurita out --sep '\t' iris.tsv < iris.csv

Getting help

The full set of command line arguments for out can be obtained with the -h or --help arguments:

gurita out -h

Specify the field separator

--sep STR

See also specifying the field separator in the input and output documentation.

By default Gurita assumes that the field separator for input data is a comma, and thus input data defaults to CSV format.

This can be overridden by the --sep argument.

For example, setting --sep to a tab character will allow TSV data to be read instead:

gurita out --sep '\t' example.tsv < example.csv

Note

It is recommended to surround the separator string in single quotes to make sure it is treated as a literal string and not interpreted to have special meaning by the shell.

Separators longer than 1 character and different from ‘s+’ will be interpreted as regular expressions. This feature should be used with caution because it is prone to incorrectly handle quoted data.

Specify the missing value markers

--na STR

See also the missing values documentation.

By default missing values will be written as empty fields in the output data. This can be overwritten with the --na STR where STR indicates the text to be used for missing values.

For example, suppose you want to use NA for missing values, then you can specify this as follows:

gurita out --na 'NA' < example.csv

Note

It is recommended to surround the missing value string in single quotes to make sure it is treated as a literal string and not interpreted to have special meaning by the shell.

Optional output file

As its last argument, the out command takes an optional output file name.

If no file name is specified then Gurita will write output to standard output. Otherwise it will try to write to the named file.

For example, the following command writes output to a named CSV file called example.csv:

gurita ... + out example.csv

The following command writes outut to a TSV file called example.tsv:

gurita ... + out --sep '\t' example.tsv

In the following command, no file name is supplied as an argument to out. In this case Gurita will write output to the standard output.

gurita ... + out --sep '\t'

Writing output inside a command chain

Gurita allows you to use out multiple times within a command chain, for example:

gurita <command_1> + out example_1.csv + <command_2> + out example_2.csv

When out is used within a command chain it receives data from the left hand side of the chain, writes the data to a file or standard output, and then passes the data along to the right hand side of the chain.

In the example above, <command_1> passes data to the first out command, which writes the data to the file called example_1.csv. The same data is then passed along unchanged to <command_2>, the output of which is then passed to the second out command, which writes the data to the file called example_2.csv.

Gurita allows you to use out to write to standard output (stdout) more than once in the same command chain. In this circumstance each output will be appended together into the same standard output stream in order from left to right. This is on contrast to the in command which only allows to read from standard input stdin) once.