sortDataset

This function is used by Ignition's Expression language.

Description

Takes a dataset and returns a sorted version of dataset. The sort order is determined by a single column. This works on numeric, as well as alphanumeric columns. When sorting alphanumerically, contiguous numbers are treated as a single number: you may recognize this as a "natural sort".

Sort Order

The table below represents an example of how alphanumeric values are sorted by the function (assuming a natural sort). Where Raw Column Values represents an initial set of values, and the Sorted columns show how the function sorts in Ascending and Descending order.

Raw Column Values	Sorted - Ascending	Sorted - Descending
a1	a1	Z3
A1	Z3	A1
a4	a22	a22
a7z9	z3	a1
a22	A1	z3
a77z4	a77z4	a7z9
a77z99	a77z99	a4
Z3	a4	a77z99
z3	a7z9	a77z4

Some caveats to be aware of:

• Null values for string columns are sorted first
• Null values for numeric columns are sorted last
• Casing is not used as a method of sorting. If the only difference between two cells is the casing, then the resulting order depends largely on where the cells were in the raw column.

Syntax (index)

sortDataset(dataset, colIndex, [ascending], [naturalOrdering])

• Parameters

  • DataSet dataset - The starting dataset.

  • Integer colIndex - The index of the column to sort on.

  • Boolean ascending - A flag indicating whether or not to sort ascending. Defaults to true. [optional]

  • Boolean naturalOrdering - A flag indicating the ordering method. True for natural, false for alphabetical. Defaults to true. [optional]

• Results

  • DataSet - A sorted dataset

Syntax (name)

sortDataset(dataset, colName, [ascending], [naturalOrdering])

• Parameters

  • DataSet dataset - The starting dataset.

  • String colName- The name of the column to sort on.

  • Boolean ascending - A flag indicating whether or not to sort ascending. Defaults to true. [optional]

  • Boolean naturalOrdering - A flag indicating the ordering method. True for natural, false for alphabetical. Defaults to true. [optional]

• Results

  • DataSet - A sorted dataset

Examples

Code Snippet

sortDataset(dataset, 0, true) // returns a Dataset sorted ascending on column 0.

Code Snippet

sortDataset(dataset, "Column 1", false) // returns a Dataset sorted descending on the column named "Column 1".