Subtracting a field value from another field value

[CAsba]

Hi,
I've tried

Code: Select all

put fld "xxxx" into txxxx
   put fld "fstock" into tfstock
   subtract txxxx from tfstock
   #put (fld "fstock" - fld "xxxx") into fld "fstock"
   
   put tfstock into tstock
   put tstock into theDataA["stock"]

Such a simple thing (!!) it would seem, but it's cost me many frustrating minutes, without success.
Please help.

[Klaus]

Did you "extract" theDataA from your datagrid first?
Don't see this in the code snippet.

And then you need of course write the array theDataA back into your datagid.

[CAsba]

I think I did all that, here's the complete snippet:

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put fld "xxxx" & TAB into tCode
   put the dgtext of grp "datagrid 3" into tText
   put lineoffset(tCode,tText) into tline
   if tLine = 0 then
      beep
      answer "No such code!"
      exit to top
   end if
   
   put line tLine of tText into tFoundLine
   #put tfoundline into fld "xxxx"
   set itemdel to TAB
   set the dghilite of grp "datagrid 3" to tfoundline 
   
   put the dgHilitedLines of group "Datagrid 3" into theLine   
   put the dgDataOfLine[theLine] of group "Datagrid 3" into theDataA
   put theDataA["stock"]into fld "fstock"
   put fld "xxxx" into txxxx
   put fld "fstock" into tfstock
   subtract txxxx from tfstock
   #put (fld "fstock" - fld "xxxx") into fld "fstock"
   
   put tfstock into tstock
   put tstock into theDataA["stock"]

[Klaus]

Yor forgot this at the end:

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...
   put tfstock into tstock
   put tstock into theDataA["stock"]

   ## This one:
   set the dgDataOfLine[theLine] of group "Datagrid 3" to theDataA
...

[Klaus]

Hint:

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...
 set the dghilite of grp "datagrid 3" to tfoundline 
...

the dgHilite is BOOLEAN value, so either TRUE or False!
Take a look in the dictionary for further infos.

[CAsba]

Hi Klaus,
Thanks for that.
There's still a problem though at the line

Code: Select all

   subtract txxxx from tfstock

error type subtract: error in source expression.
I'm baffled.

[Klaus]

Hm, syntax is correct!?
Make sure there are definitively NUMBERS in those fields.

[dunbarx]

CAsba.

Not sure what your actual data is, but that error comes when the values in those variables are not numeric. You cannot, say, subtract "42" from "A106"

Craig