KDAriane

h1. Eval101

h2. Synopsis

This operator has only one parameter and no input. The corresponding shell script executes the parameter as a command, and copies the result in the output.

h2. Parameters

1 parameter, treated as the command to be executed. The command can contains spaces, such as @ls -al@, @date -R@.

h2. Inputs

No input

h2. Outputs

1 output: the result of the command

h2. Shell code

<pre>

cmd=$1; shift

output=$1; shift

$cmd > $output

</pre>

h2. Example

This operator can be used for generating a file, containing the current date for example, with "date" as a parameter.

See the scenario [[Perturbation with RapidMiner]], where this operator initiates an "empty" file with only the date for a "for" loop.