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loop through columns with similar names

qt

Community Trekker

Joined:

Oct 17, 2012

Hi, JMP experts,

Is there an easier way to loop through JMP data file with many columns?

My data file has columns:

Err_Loc_0_Time_0

Err_Loc_0_Time_1

Err_Loc_0_Time_2

Err_Loc_0_Time_3

....

Err_Loc_0_Time_20

Err_Loc_1_Time_0

Err_Loc_1_Time_1

Err_Loc_1_Time_2

.....

Err_Loc_1_Time_20

Err_Loc_2_Time_0

.....

Err_Loc_30_Time_20

So Loc can change from 0-30, Time change from 0-20.

If I want to do a transpose:

Data Table( data_table ) << Transpose(

columns(

:Err_Loc_0_Time_0

:Err_Loc_0_Time_1

:Err_Loc_0_Time_2

:Err_Loc_0_Time_3

....

:Err_Loc_0_Time_20

:Err_Loc_1_Time_0

:Err_Loc_1_Time_1

:Err_Loc_1_Time_2

.....

:Err_Loc_1_Time_20

:Err_Loc_2_Time_0

),

);

So I have to copy and paste the column name one by one, can I use some I, J loop?

For I=0,30

For J=0,20

:Err_Loc_I_Time_J

....

Can somebody please tell me how to do this?

Thanks,

Qian

2 REPLIES
ms

Super User

Joined:

Jun 23, 2011

Transpose can use a list of columns, so something like this should work:

dt = Current Data Table();

col_list = {};

For( i = 0, i <= 30, i++,

  For( j = 0, j <= 20, j++,

  Insert Into( col_list, Parse( ":Err_Loc_" || Char( i ) || "_Time_" || Char( j ) ) )

  )

);

dt << Transpose( columns( Eval( col_list ) ) );

qt

Community Trekker

Joined:

Oct 17, 2012

MS, thanks!

It works.

It is very cool we can loop through columns with index.

Best regards,

Qian