Question about function Previous()

[#1]

Hi,

please, look at my script:

load

  id,

  text,

  balance,

  Previous(debt) - balance as debt

;

load * inline [

id, text, balance, debt

0,,,400

1, aaa, 250, 0

2, bbb, 200, 0

3, ccc, 100, 0

];

I expected this:

0,       ,      , -

1, aaa, 250, 150

2, bbb, 200, -50

3, ccc, 100, -150

but, result is:

0,       ,      , -

1, aaa, 250, 150

2, bbb, 200, -200

3, ccc, 100, -100

What's wrong in my script?

Thanks in advance!

[prat1507]

Previous(debt) returns

-

400

0

0

which when evaluated as Previous(debt)-balance gives

-

150

-200

-100

Regards

Pratyush

[vinieme12]

Debt is 0 for all except the first row, I think you want this

Load

  id,

  text,

  balance,

  balance - Previous(balance) as debt

;

load * inline [

id, text, balance, debt

0,,400,

1, aaa, 250, 0

2, bbb, 200, 0

3, ccc, 100, 0

];

[settu_periasamy]

Try this..

Load
id,
text,
balance,
Previous(balance) as Prev,
if(RowNo()>2, Peek(dept)-balance,Previous(balance)-balance) as dept
;