cumulative sumIs there a simple way to calculate the cumulative sum when there is a group and subgroup that are to be cumulative sum. Shown in the following picture, I want to calculate cumulative sum for batch 1 and all sample a, then batch 1 and all sample b and then batch 1 and all sample c.

Data TableRe: cumulative sumFrom your description, it sounds like a simple tabulate will give you what you want (script in the attached file - with the batch changed to nominal data type). However, if you want a formula for the cumulative sum, you can use the Cumulative Sum function (found in the Statistics functions) using both batch and sample as By variables (but that gives a running total by row, not the overall cumulative sum like the tabulation will give).
Re: cumulative sumHI @billi,
You can add a right-click formula column for cumulative sum.
Right-Click on a column and choose New Formula Column.
Choose Row--Cumulative Sum
JMP New Formula Column
Edit formula to add by variable using "^" insert
This will calculate the cumulative sum as shown in the image below.
Cumulative Sum with By variable
I have attached a modified version of your data table with the included column formula.
cheers,
Stan