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UNPIVOT GS
/**
* Unpivot a pivot table of any size.
*
* @param {A1:D30} data The pivot table.
* @param {1} fixColumns Number of columns, after which pivoted values begin. Default 1.
* @param {1} fixRows Number of rows (1 or 2), after which pivoted values begin. Default 1.
* @param {"city"} titlePivot The title of horizontal pivot values. Default "column".
* @param {"distance"[,...]} titleValue The title of pivot table values. Default "value".
* @return The unpivoted table
* @customfunction
*/
function unpivot(data,fixColumns,fixRows,titlePivot,titleValue) {
var fixColumns = fixColumns || 1; // how many columns are fixed
var fixRows = fixRows || 1; // how many rows are fixed
var titlePivot = titlePivot || 'column';
var titleValue = titleValue || 'value';
var ret=[],i,j,row,uniqueCols=1;
// we handle only 2 dimension arrays
if (!Array.isArray(data) || data.length < fixRows || !Array.isArray(data[0]) || data[0].length < fixColumns)
throw new Error('no data');
// we handle max 2 fixed rows
if (fixRows > 2)
throw new Error('max 2 fixed rows are allowed');
// fill empty cells in the first row with value set last in previous columns (for 2 fixed rows)
var tmp = '';
for (j=0;j<data[0].length;j++)
if (data[0][j] != '')
tmp = data[0][j];
else
data[0][j] = tmp;
// for 2 fixed rows calculate unique column number
if (fixRows == 2)
{
uniqueCols = 0;
tmp = {};
for (j=fixColumns;j<data[1].length;j++)
if (typeof tmp[ data[1][j] ] == 'undefined')
{
tmp[ data[1][j] ] = 1;
uniqueCols++;
}
}
// return first row: fix column titles + pivoted values column title + values column title(s)
row = [];
for (j=0;j<fixColumns;j++) row.push(fixRows == 2 ? data[0][j]||data[1][j] : data[0][j]); // for 2 fixed rows we try to find the title in row 1 and row 2
for (j=3;j<arguments.length;j++) row.push(arguments[j]);
ret.push(row);
// processing rows (skipping the fixed columns, then dedicating a new row for each pivoted value)
for (i=fixRows;i<data.length && data[i].length > 0;i++)
{
// skip totally empty or only whitespace containing rows
if (data[i].join('').replace(/\s+/g,'').length == 0 ) continue;
// unpivot the row
row = [];
for (j=0;j<fixColumns && j<data[i].length;j++)
row.push(data[i][j]);
for (j=fixColumns;j<data[i].length;j+=uniqueCols)
ret.push(
row.concat([data[0][j]]) // the first row title value
.concat(data[i].slice(j,j+uniqueCols)) // pivoted values
);
}
return ret;
}
@AbyssFolk
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AbyssFolk commented Jan 9, 2023

If you have csv like

Name, cat 1, cat 2, cat 3, cat 4

and you want to flatten it for look up purpopses

you wil have to UNPIVOT

to do so..

make the data do the following

Name,Name,Name,Name,cat 1, cat 2, cat 3, cat 4

Then Flatten the first 4 columns

and then next to it flatten the next 4 columns,

it should alone

Name,Cat 1
Name, Cat 2
Name, Cat 3,
Name, Cat 4

Right?

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