sortRowIndices function

float[] sortRowIndices(array)

array float[]string[] Array to be sorted.

Returns the indices of sorted rows in array.

The size of the returned index array equals the number of rows of array. Duplicate rows are sorted in the order of appearance.

array =                                                  [4,0,1;
                                                          2,1,9;
                                                          1,3,0;
                                                          2,1,0]

sortRowIndices(array) =                                  [2,3,1,0]

array[sortRowIndices(array),0:nColumns(array)-1] =       [1,3,0;
                                                          2,1,0;
                                                          2,1,9;
                                                          4,0,1]

Related

Array types operators findFirstfunction sortIndicesfunction

Example

Sort rows by column precedence

const a = [4,0,1;
           2,1,9;
           1,3,0;
           2,1,0]

sortRows(a,columnPrecedence) = a[sortRowIndices(a[0:nRows(a)-1,columnPrecedence]),0:nColumns(a)-1]

// sort by column 1
const b = sortRows(a,1) // [4,0,1;
                        //  2,1,9;
                        //  2,1,0;
                        //  1,3,0]

// sort by column 1, then column 0, then column 2
const c = sortRows(a,[1,0,2]) // [4,0,1;
                              //  2,1,0;
                              //  2,1,9;
                              //  1,3,0]