Parse column names in Chart

katief

This question is similar to another post about how to parse chart column names.
I want to create a simple bar chart where my Y columns are determined by user selection from a col list box.

I can't figure out a way to use parse and or expr to put my user selections into the chart statement.

For other types of charts (like Overlay), I have been able to use a list of columns to do this, but I can't

seem to do that with chart.

This code generates the graph when the Ycols are known:

dt =  Open("$ENGLISH_SAMPLE_DATA/Big Class.jmp");

Chart (X( :name )

,

Y( :height, :weight )

);

When I have user selected YCols, I need to do something like this:

Chart1Expr= expr(Chart(

X(:name),

Y(ycols)

));

replaceycols = expr(:height, :weight) <- this doesn't work, but it's like what I need

newchartexpr = substitute(name expr(Chart1Expr), expr(ycols), expr(replaceycols));

newchartexpr;

ms

Y() can accept a list as argument, even when the column names are represented by strings. This example works in JMP9:

dt = Open( "$ENGLISH_SAMPLE_DATA/Big Class.jmp" );

ycols = {"height", "weight"};

Chart( X( :sex ), Y( Eval( ycols ) ) );

However, if you need to specify any statistics it gets a little more complicated. One method is to build a list of expressions by looping through a list (e.g. generated by user) like in he below example:

dt = Open( "$ENGLISH_SAMPLE_DATA/Big Class.jmp" );

ycols = {};

For( i = 1, i <= N Items( ylist ), i++,

          Insert Into( ycols, Parse( "Mean(:" || ylist[i] || ")" ) ) 

);

Chart( X( :sex ), Y( Eval( ycols ) ) );