Hi everyone -
I'm looking for a column formula that would return the following desired column below. For simplicity in this post each group has 3 rows, but the dataset I currently have has groups with varying numbers of rows.
Any help appreciated!
| Group | Time | Score | First Time Failed (Desired Column) |
| A | 1 | Pass | 8 |
| A | 3 | Pass | 8 |
| A | 8 | Fail | 8 |
| B | 1 | Pass | Pass |
| B | 2 | Pass | Pass |
| B | 6 | Pass | Pass |
| C | 1 | Pass | 3 |
| C | 3 | Fail | 3 |
| C | 7 | Fail | 3 |
@user8421 ,
This is just a fun alternative that uses data table formulas. It will work for unequal Group sizes and if the table is not sorted.
The logic is to find the minimum row number for Fails in each Group. Col Minimum(... , By) is the key. Column statistic functions using the By option are very useful, but often overlooked functions.
Formula for column "Row First Failed"
Formula for column "Time First Failed". Note if the syntax seems strange, the right-hand formula is Time, then select Subscript from the Row functions and drag column 4, "Row First Failed"
Here is a formula that works with your Example data table. It has not been tested beyond that, so you may need to make some adjustments
Names Default To Here( 1 );
dt = New Table( "Example",
Add Rows( 9 ),
New Column( "Group", Character, "Nominal", Set Values( {"A", "A", "A", "B", "B", "B", "C", "C", "C"} ) ),
New Column( "Time", Numeric, "Continuous", Format( "Best", 12 ), Set Values( [1, 3, 8, 1, 2, 6, 1, 3, 7] ) ),
New Column( "Score",
Character,
"Nominal",
Set Values( {"Pass", "Fail", "Pass", "Pass", "Pass", "Pass", "Pass", "Fail", "Fail"} )
)
);
dt << New Column( "First Time Failed",
character,
formula(
If( Row() == 1,
dt = Current Data Table();
check = :Score;
If( :Group == :Group[2],
Failed = Char( Col Max( :Time, :Group ), Failed = :Score )
);
,
If( :Group == Lag( :Group ),
If( :Score == "Fail",
check = "Fail"
);
Failed = Char( Col Max( :Time, :Group ) );
,
If( check == "Pass",
lagGroup = Lag( :Group );
:First Time Failed[dt << get rows where( :Group == lagGroup )] = "Pass";
Failed = Char( Col Max( :Time, :Group ) );
);
check = :Score;
)
);
failed;
)
);
