Fast delete collumns from big array

[Allow2010]

Hello,

i have a very big array (3000+ rows and 158 cols).

From this array only cols 1-19 are needed.

In order to save some memory, i would like to delete unneeded info.

I tried

For $i = 158 To 20 Step -1
        _ArrayColDelete($localdb, $i)
    Next

and this seems to work fine, but it takes more than 20 seconds.

Is there a faster way?

All ideas welcome :-)

[Jos]

ReDim ?

Jos

[Allow2010]

oh yes, never needed it before :-) Thanks a lot!

[BrewManNH]

How is this array created in the first place, and can't you prevent the extra columns from being created so you don't have to remove them?

[dmob]

 

20 hours ago, Allow2010 said:

From this array only cols 1-19 are needed.

l would use _ArrayExtract.

[water]

As Jos suggested (untested):

#include <Array.au3>
; Example with 30 rows and 158 columns resized to the same number of rows and 19 columns
Global $aArray[30][158] ; Define array holding 30 rows x 158 columns
$aArray[0][18] = "Row 1, Column 19"
$aArray[0][157] = "Row 1, Column 158"
_ArrayDisplay($aArray, "Before ReDim")
ReDim $aArray[UBound($aArray, 1)][19] ; Resize to the current number of rows x 19 columns
_ArrayDisplay($aArray, "After ReDim")

 

[Allow2010]

Hello,

 

as the array is the result of an sql request, i can not keep the array smaller (at least not in a simple way).

the redim method works very good for me, but _ArryExtract is also a good option.

Thanks for the help!

 

[jchd]

3 hours ago, Allow2010 said:

as the array is the result of an sql request, i can not keep the array smaller (at least not in a simple way)

That's strange! Precisely because this is the output of an SQL query can you specify exactly the columns you need, e.g.

select this, that from ...
instead of
select * from ... 

[Allow2010]

yes, but in this case i can not change the query, i just have to live with the reslt...but thank you .-)