Spotfire how to make calculation along one coloumn - calculated-columns

Question

I have a data table as below.I would like to create a new column called "Time Difference" which captures the time difference between [STAGE] start and [STAGE] end. Is there any way to do it without using data transformation?
Thank you!

Answer 1

Assuming each ID is unique, and your data is ordered by Time where Stage = Start is the first row for each ID and Stage = End is the last row for each ID, you can use this:
Concatenate(Min([Time]) OVER ([ID]),"-",Max([Time]) over ([ID]))
RESULTS
+----+---------+---------+------+-----------------+
| ID | Stage | Action | Time | Time Difference |
+----+---------+---------+------+-----------------+
| 1 | Start | approve | A | A-F |
| 1 | Process | approve | B | A-F |
| 1 | Process | approve | C | A-F |
| 1 | Process | approve | D | A-F |
| 1 | Process | decline | E | A-F |
| 1 | End | approve | F | A-F |
| 2 | Start | approve | G | G-I |
| 2 | Process | decline | H | G-I |
| 2 | End | approve | I | G-I |
+----+---------+---------+------+-----------------+
If your data isn't already sorted, you can just apply a Rank() to fix this. Let me know if that's the case.
EDIT WITH NEW DATA
EXPRESSION
Concatenate(Min(If((Upper([Stage])="START") and (Upper([Action])="APPROVE"),Max([Time]) OVER ([ID]))) OVER ([ID]),"-",Min(If((Upper([Stage])="END") and (Upper([Action])="APPROVE"),Max([Time]) OVER ([ID]))) OVER ([ID]))
Simplified
Concatenate(Min(If((Upper([Stage])="START") and (Upper([Action])="APPROVE"),[Time])) OVER ([ID]),"-",Min(If((Upper([Stage])="END") and (Upper([Action])="APPROVE"),[Time])) OVER ([ID]))
RESULTS
+----+---------+---------+------+-----------------+
| ID | Stage | Action | Time | Time Difference |
+----+---------+---------+------+-----------------+
| 1 | On hold | decline | A | C-H |
| 1 | Start | decline | B | C-H |
| 1 | Start | approve | C | C-H |
| 1 | Process | DECLINE | D | C-H |
| 1 | Process | approve | E | C-H |
| 1 | Process | approve | F | C-H |
| 1 | End | decline | G | C-H |
| 1 | End | approve | H | C-H |
| 2 | Start | approve | I | I-K |
| 2 | Process | decline | J | I-K |
| 2 | End | approve | K | I-K |
+----+---------+---------+------+-----------------+