Creating a Column with the Cumulative Percentage

Hi, hope everyone is doing well,

I have a column with values, sorted in descending order, and I want to create a second column with the cumulative percentage of the first column’s total (end results would be the third column in the example below).

Picture1

This would be simple in Excel as I could just input the formula “=A2/SUM($A$2:$A$5)” on the third column’s first row, “=(A3/SUM($A$2:$A$5)) + 1” on the second row and so on. Another alternative would be having the formula “=IF(ROW(A2)=2;A2/SUM($A$2:$A$5);(A2/SUM($A$2:$A$5))+C1)” or something similar, therefore having a single formula.

I could use the Math Formula node to do the $column$/COL_SUM($column$), which would get me the percentage of that specific row, but I don’t know how to reference row/cell position for the cumulative sum.

Is there any way to do this? Additionally, any recommendations of reading material for KNIME formula’s syntax would be really helpful, I’m a bit of an Excel rat, I guess KNIME will take some getting used to!

Thanks a mill

Hi there!

Sure there is a way! For calculating cumulative sum you can use multiple nodes. Try Moving Aggregation node with Cumulative computation checked and and Aggregation method on wanted column to be sum :wink:

You can also use Java Snippet (simple) node if you prefer coding :wink:

If you are coming from Excel check this out:

https://www.knime.com/knimepress/from-excel-to-knime

Br,
Ivan

4 Likes

Worked perfectly, cheers! And thanks for the tip!

2 Likes

You are welcome :wink:
Ivan

1 Like

This topic was automatically closed 7 days after the last reply. New replies are no longer allowed.