Subtract during load?

[alenb]

I wonder if something like this is possible. If I have data like this:

UNITS: Load * Inline [
Month, Return, Units
  10, , 5
  10, , 5
  10, x, 3
  11, , 2
  11, , 2
];

I should subtract the values where Return=x. 

Load 
  Month,
  Sum(Units, where Return ='') - Sum(Units, where Return=x) as Units  // <- I'm making this up
Resident UNITS; 

And the result would be 

Month, Units
10, 7
11, 4

[QFabian]

hI, @alenb ,!, very fun load, check this please :

UNITS:
Load * Inline [
Month, Return, Units
10, , 5
10, , 5
10, x, 3
11, , 2
11, , 2
];

Load
recno() as Id,
Month,
Return,

Units,
if(rowno()=1, Units,if(Return='x',-Units, Units)) as UnitsForSum

Resident UNITS;

drop table UNITS;

[MayilVahanan]

Hi @alenb 

Load Month, Units, If(Len(Trim(Return))=0, Units, -Units) as Return Inline [
Month, Return, Units
10, , 5
10, , 5
10, x, 3
11, , 2
11, , 2
];

Dim: Month
Measure: Sum(Return) , Sum(Units)

[alenb · Accepted solution]

I actually stated the problem wrongly, but thanks anyway, the IF statement was what I needed. What I ended up doing was just flipping the number to negative if Return=X, and after that all the sum expressions started working correctly.

if(Return='x',-Units, Units)) as Units

[QFabian]

it´s amazing when you start to understand how qlik works on loading, first you could think a complex formula to solve it, but after look at the data in qlik, you just create perfect and simple formulas like you did.