How do you create a “reverse pivot” in Google Sheets?

问题

I am trying to produce a \"reverse pivot\" function. I have searched long and hard for such a function, but cannot find one that is already out there.

I have a summary table with anywhere up to 20 columns and hundreds of rows, however I would like to convert it into a flat list so I can import to a database (or even use the flat data to create more pivot tables from!)

So, I have data in this format:

          | Customer 1 | Customer 2 | Customer 3
----------+------------+------------+-----------
Product 1 |          1 |          2 |          3
Product 2 |          4 |          5 |          6
Product 3 |          7 |          8 |          9

And need to convert it to this format:

 Customer  |  Product  | Qty
-----------+-----------+----
Customer 1 | Product 1 |   1
Customer 1 | Product 2 |   4
Customer 1 | Product 3 |   7
Customer 2 | Product 1 |   2
Customer 2 | Product 2 |   5
Customer 2 | Product 3 |   8
Customer 3 | Product 1 |   3
Customer 3 | Product 2 |   6
Customer 3 | Product 3 |   9

I have created a function that will read the range from sheet1 and append the re-formatted rows at the bottom of the same sheet, however I am trying to get it working so I can have the function on sheet2 that will read the whole range from sheet1.

No matter what I try, I can\'t seem to get it to work, and was wondering if anybody could give me any pointers?

Here is what I have so far:

function readRows() {
  var sheet = SpreadsheetApp.getActiveSheet();
  var rows = sheet.getDataRange();
  var numRows = rows.getNumRows();
  var values = rows.getValues();

  heads = values[0]

  for (var i = 1; i <= numRows - 1; i++) {
    for (var j = 1; j <= values[0].length - 1; j++) {
       var row = [values[i][0], values[0][j], values[i][j]];
       sheet.appendRow(row)
    }
  }
};

回答1:

I wrote a simple general custom function, which is 100% reusable you can unpivot / reverse pivot a table of any size.

In your case you could use it like this: =unpivot(A1:D4,1,1,"customer","sales")

So you can use it just like any built-in array function in spreadsheet.

Please see here 2 examples: https://docs.google.com/spreadsheets/d/12TBoX2UI_Yu2MA2ZN3p9f-cZsySE4et1slwpgjZbSzw/edit#gid=422214765

The following is the source:

/**
 * 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;
}

回答2:

That is basically array manipulation... below is a code that does what you want and writes back the result below existing data.

You can of course adapt it to write on a new sheet if you prefer.

function transformData(){
  var sheet = SpreadsheetApp.getActiveSheet();
  var data = sheet.getDataRange().getValues();//read whole sheet
  var output = [];
  var headers = data.shift();// get headers
  var empty = headers.shift();//remove empty cell on the left
  var products = [];
    for(var d in data){
      var p = data[d].shift();//get product names in first column of each row
      products.push(p);//store
    }
  Logger.log('headers = '+headers);
  Logger.log('products = '+products);
  Logger.log('data only ='+data);
  for(var h in headers){
    for(var p in products){  // iterate with 2 loops (headers and products)
      var row = [];
      row.push(headers[h]);
      row.push(products[p]);
      row.push(data[p][h])
      output.push(row);//collect data in separate rows in output array
    }
  }
  Logger.log('output array = '+output);
  sheet.getRange(sheet.getLastRow()+1,1,output.length,output[0].length).setValues(output);
}

to automatically write the result in a new sheet replace last line of code with these :

  var ns = SpreadsheetApp.getActive().getSheets().length+1
  SpreadsheetApp.getActiveSpreadsheet().insertSheet('New Sheet'+ns,ns).getRange(1,1,output.length,output[0].length).setValues(output);

回答3:

I didn't think you had enough array formula answers so here's another one.

Test Data (Sheet 1)

Formula for customer

=ArrayFormula(hlookup(int((row(indirect("1:"&Tuples))-1)/Rows)+2,{COLUMN(Sheet1!$1:$1);Sheet1!$1:$1},2))

(uses a bit of math to make it repeat and hlookup to find correct column in column headers)

Formula for product

=ArrayFormula(vlookup(mod(row(indirect("1:"&Tuples))-1,Rows)+2,{row(Sheet1!$A:$A),Sheet1!$A:$A},2))

(similar approach using mod and vlookup to find correct row in row headers)

Formula for quantity

=ArrayFormula(vlookup(mod(row(indirect("1:"&Tuples))-1,Rows)+2,{row(Sheet1!$A:$A),Sheet1!$A:$Z},int((row(indirect("1:"&Tuples))-1)/Rows)+3))

(extension of above approach to find both row and column in 2d array)

Then combining these three formulas into a query to filter out any blank values for quantity

=ArrayFormula(query(
   {hlookup(int((row(indirect("1:"&Tuples))-1)/Rows)+2, {COLUMN(Sheet1!$1:$1);Sheet1!$1:$1},2),
    vlookup(mod(row(indirect("1:"&Tuples))-1,Rows)+2,{row(Sheet1!$A:$A),Sheet1!$A:$A},2),
    vlookup(mod(row(indirect("1:"&Tuples))-1,Rows)+2,{row(Sheet1!$A:$A),Sheet1!$A:$Z},int((row(indirect("1:"&Tuples))-1)/Rows)+3)},
"select * where Col3 is not null"))

Note

The named ranges Rows and Cols are obtained from the first column and row of the data using counta and Tuples is their product. The separate formulas

=counta(Sheet1!A:A)

=counta(Sheet1!1:1)

and

=counta(Sheet1!A:A)*counta(Sheet1!1:1)

could be included in the main formula if required with some loss of readability.

For reference, here is the 'standard' split/join solution (with 50K data limit) adapted for the present situation:

=ArrayFormula(split(transpose(split(textjoin("♫",true,transpose(if(Sheet1!B2:Z="","",Sheet1!B1:1&"♪"&Sheet1!A2:A&"♪"&Sheet1!B2:Z))),"♫")),"♪"))

This is also fairly slow (processing 2401 array elements). If you restrict the computation to the actual dimensions of the data, it is much faster for small datasets:

=ArrayFormula(split(transpose(split(textjoin("♫",true,transpose(if(Sheet1!B2:index(Sheet1!B2:Z,counta(Sheet1!A:A),counta(Sheet1!1:1))="","",Sheet1!B1:index(Sheet1!B1:1,counta(Sheet1!1:1))&"♪"&Sheet1!A2:index(Sheet1!A2:A,counta(Sheet1!A:A))&"♪"&Sheet1!B2:index(Sheet1!B2:Z,counta(Sheet1!A:A),counta(Sheet1!1:1))))),"♫")),"♪"))

回答4:

Here is a demo file that uses a method using built-in custom functions and array formulas:

Create a new sheet and rename it as "Aux"
In the Aux sheet add the following formulas: (this assumes that the source data is in a sheet named data)
A1: =COUNTA(data!A:A) Calculate the number of rows.
A2: =COUNTA(data!1:1) Calculate the number of columns.
A3: =CELL("address",data!A1) Intermediate step.
A4: =LEFT(A3,FIND("!",A3)-1) Calculates the name of the sheet with the source data.
Create a new sheet
Add the following the new sheet
A1: Row headers
A2:

=ArrayFormula(
  VLOOKUP(
    MOD(ROW(INDIRECT("A1:A"&Aux!A1*Aux!A2))-1,Aux!A1)+1+1,
    {(ROW(INDIRECT("A1:A"&Aux!A1+1))),INDIRECT(Aux!A4&"!R1C1:R"&Aux!A1+1&"C"&Aux!A2+1,false)},
    2
  )
)

B1: Column headers
B2:

=ArrayFormula(
  VLOOKUP(
    SIGN(ROW(INDIRECT("A1:A"&Aux!A1*Aux!A2))),
    {(ROW(INDIRECT("A1:A"&Aux!A1+1))),INDIRECT(Aux!A4&"!R1C1:R"&Aux!A1+1&"C"&Aux!A2+1,false)},
    MOD(ROW(INDIRECT("A1:A"&Aux!A1*Aux!A2))-1,Aux!A2)+1+2
  )
)

C1: Values
C2:

=ArrayFormula(
  VLOOKUP(
    MOD(ROW(INDIRECT("A1:A"&Aux!A1*Aux!A2))-1,Aux!A1)+1+1,
    {(ROW(INDIRECT("A1:A"&Aux!A1+1))),INDIRECT(Aux!A4&"!R1C1:R"&Aux!A1+1&"C"&Aux!A2+1,false)},
    MOD(ROW(INDIRECT("A1:A"&Aux!A1*Aux!A2))-1,Aux!A2)+1+2
  )
)

Description of the main constructs

ROW(INDIRECT("A1:A"&Aux!A1*Aux!A2) returns an array of consecutive numbers that has the same height as the required final result.
{(ROW(INDIRECT("A1:A"&Aux!A1+1))),INDIRECT(Aux!A4&"!R1C1:R"&Aux!A1+1&"C"&Aux!A2+1,false)} returns a array with the first column including the row index, and the next columns are the source data.

回答5:

If your data has a single unique key column, this spreadsheet may have what you need.

Your unpivot sheet will contain:

The key column =OFFSET(data!$A$1,INT((ROW()-2)/5)+1,0)
The column header column =OFFSET(data!$A$1,0,IF(MOD(ROW()-1,5)=0,5,MOD(ROW()-1,5)))
The cell value column =INDEX(data!$A$1:$F$100,MATCH(A2,data!$A$1:$A$100,FALSE),MATCH(B2,data!$A$1:$F$1,FALSE))

where 5 is the number of columns to unpivot.

I did not make the spreadsheet. I happened across it in the same search that led me to this question.

回答6:

=ARRAYFORMULA({"Customer", "Product", "Qty"; 
 QUERY(TRIM(SPLIT(TRANSPOSE(SPLIT(TRANSPOSE(QUERY(TRANSPOSE(QUERY(TRANSPOSE(
 IF(B2:Z<>"", B1:1&"♠"&A2:A&"♠"&B2:Z&"♦", )), , 999^99)), , 999^99)), "♦")), "♠")), 
 "where Col1<>'' order by Col1")})

回答7:

Array manipulation using array.reduce and array.splice - minimalistic approach:

/**
 * Unpivots the given data
 *
 * @return Unpivoted data from array
 * @param {A1:F4} arr 2D Input Array
 * @param {3} numCol Number of static columns on the left
 * @param {A1:C1} headers [optional] Custom headers for output
 * @customfunction
 */
function unpivot(arr, numCol, headers) {
  var out = arr.reduce(function(acc, row) {
    var left = row.splice(0, numCol); //static columns on left
    row.forEach(function(col, i) {
      acc.push(left.concat([acc[0][i + numCol], col])); //concat left and unpivoted right and push as new array to accumulator
    });
    return acc;
  }, arr.splice(0, 1));//headers in arr as initial value
  headers ? out.splice(0, 1, headers[0]) : null; //use custom headers, if present.
  return out;
}

Usage:

=UNPIVOT(A1:F4,1,{A1,"Month","Sales"})//Outputs 1 static and 2 unpivoted columns from 1 static and 4+ pivoted columns

来源：https://stackoverflow.com/questions/24954722/how-do-you-create-a-reverse-pivot-in-google-sheets

标签

google-apps-script

google-sheets

pivot-table

unpivot