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Can I use quote marks on column names in a formula?

Hi,

 

I have the following simplified script in a table:

 

dataTable = Current Data Table();
If( !Contains( strColNames, "pears" ),
    dataTable << New Column( "pears",
        numeric,
        "Continuous",
        Formula( :"apples" + 2 )
    )
);

When I copy this script to a new table (using ctrl-c ctrl-v), which already has a filled column named "apples", the script ends up as:

dataTable = Current Data Table();
If( !Contains( strColNames, "pears" ),
 dataTable << New Column( "pears",
  numeric,
  "Continuous",
  Formula( As Column() + 2 )
 )
);

The reference to the column "apples" is replaced in the formula by the As Column() statement. The script no longer works. It turns out that removing the quotation marks from the reference to the column "apples" in the formula solved the problem.

I consider this a bug. Is it, or is this expected behaviour?

 

Regards, Radko

 

Re: Can I use quote marks on column names in a formula?

I do this slightly differently.  I use the function below to create the column.  If the column exists it simply returns the column handle, if the column does not exist it creates a new column and returns the handle.  So the usage would be something like this:

 

PearCol=createcol(dt,"Pears","NUMERIC");   // "NUMERIC" or "CHARACTER"

AppleCol=createcol(dt,"Apples","NUMERIC");

PearCol<

 

I prefer to use 'set each value' but you can also set a formula if that makes more sense in your application.

 

 

 

CreateCol = Function( {ct, ccn, ColType},
{default local},
CreateColExpr = Expr(
stuff = __CurDataTable__ << New Column( __ColName__, __ColType__ )
);
stuff = Try( Column( ct, ccn ), -1 );
Wait( 0 );
If( stuff == -1,
CreateColumn = Substitute( Name Expr( CreateColExpr ),
Expr( __ColType__ ), Parse( ColType ),
Expr( __CurDataTable__ ), Eval( ct ),
Expr( __ColName__ ), Eval( ccn )
);
Show( CreateColumn );
Eval( CreateColumn );
);
stuff;
);

Re: Can I use quote marks on column names in a formula?

You will need to manually handle the quotes.  See the code below:

dataTable = Current Data Table();
If( !Contains( strColNames, "\!"pears\!"" ),
 dataTable << New Column( "\!"pears\!"",
  numeric,
  "Continuous",
  Formula( :Name( "\!"apples\!"" ) + 2 )
 )
);