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#### 4.3.4 `loop`

Usage: `:loop:<count>|<start>,<end>[,<step>]`

Generates a table whose single column increments over a given range.

The specification may either be a single value N giving the number of rows, which yields values in the range 0..N-1, or two or three comma-separated values giving the start, end and optionally step corresponding to the conventional specification of a loop variable.

The supplied numeric parameters are interpreted as floating point values, but the output column type will be 32- or 64-bit integer or 64-bit floating point, depending on the values that it has to take. Any embedded underscores will be ignored.

Examples:

- `:loop:5`: a 5-row table whose integer column has values 0, 1, 2, 3, 4
- `:loop:10,20`: a 10-row table whose integer column has values 10, 11, ... 19
- `:loop:1,2,0.25`: a 10-row table whose floating point column has values 1.00, 1.25, 1.50, 1.75
- `:loop:1e10`: a ten billion row table, with 64-bit integer values

Example:

    :loop:6
    +---+
    | i |
    +---+
    | 0 |
    | 1 |
    | 2 |
    | 3 |
    | 4 |
    | 5 |
    +---+

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TOPCAT - Tool for OPerations on Catalogues And Tables
Starlink User Note253
TOPCAT web page: http://www.starlink.ac.uk/topcat/
Author email: m.b.taylor@bristol.ac.uk
Mailing list: topcat-user@jiscmail.ac.uk