This module is rated as pre-alpha. It is unfinished, and may or may not be in active development. It should not be used other than for testing. Modules remain pre-alpha until the original editor (or someone who takes one over if it is abandoned for some time) is satisfied with the basic structure.

This module provides utility functions for transforming tabular data sets in chart renderings.

See mw:Extension:Chart/Transforms for more documentation on this transform feature of the Charts system.

Usage

select: subset a data set by column reference or comparison on row values

To use as a chart transform:

"transform": {
    "module": "TabUtils",
    "function": "select",
    "args": {
        "where": "date",
        "lte": "2000"
    }
}

To invoke as a utility function from another module:

local TabUtils = require( "Module:TabUtils" )
local tab = mw.ext.data.get( "Sample weekly temperature dataset.tab" )

-- Note this may mutate the original tab object
tab = TabUtils.select(tab, {
    ["where"] = "date",
    ["lte"] = "2000"
})

Arguments:

• cols: comma-separated list of column names to keep, otherwise returns all cols
• where: column name to match on, otherwise returns all rows
• eq, ne, gt, lt, gte, lte: value to compare against to keep rows
• sort: column name to sort on
• order: sort order "asc" or "desc", defaults to "asc"
• decimate: keep only every nth row

Todo

• support sort on multiple columns
• allow combining multiple gt/gte/lt/lte to allow ranges