I have a barchart to display the number of action on a keyboard for a time interval of 10 seconds. Without using "group by" function, I have the expected result:
http://postimg.org/image/by1vzottr/
However, I wanted to improve it by using group by function. Therefore, I categorized my Y value. EG: if Y < 10, cat = 0; if Y < 20, cat = 1 etc. But when using "Group by" option, I have this result:
http://postimg.org/image/fcx8e8j4x/
My goal is to have the first graph display, but with the colour corresponding to the categories.