I was hoping the experts here could help me out. I need to express conditional summation. Let me give you guys an example. Suppose I have a timeline like this:
Each value on the time-line in the above image represents a value in hours and the red box around the values shows that an event had occurred at that time. This is all well and good however i need a way to modify the above expression so that it considers only those values that have a red box around them and ignores the rest for example:
Correction in the image (its suppose to be 5-3 sorry about that)
Any suggestions on how i could do that would be appreciated or how the expression should look like...