Problems with invisible tables being garabage collected

Question

I want to run calculations on invisible tables to speed up excecution.

However, my invisible tables are deleted before I get to do anything useful. In the log output I get the following message:

The table 'Invisible table' was automatically closed because no variable or window refers to it.

According to the JMP Scripting Guide this is expected behaviour if the invisable table was created using the Subset(invisible) command. But I'm creating a new table using

dt = newTable("Invisible table",invisible);

The JMP Scripting Guide emphasizes that when doing this I must remember to close the table or it will stay in memory until i quit JMP. But in my case it is automatically deleted some time after my first operation on the table, even though I do assign a reference to the table. (If I create the table without the invisible option everything is working as it should)

Using JMP 8

helge · Answer

I did some more investigations, and it seems that the problem occurs when I am closing a subtable that is linked to the invisible table.

So I am doing something like this:

dt = newTable("Invisible table",invisible);

dt << Select Where( /* some selection criteria */ );

subdt = dt << Subset(output table name("subset table"),Linked);

// some operations on subdt

close(subdt,nosave)

This code is enclosed in a loop which varies the selection criteria for the Select command.

The problem is the close() command. If I do not close the subtable the reference to the invisible table does not disappear. (Also, if I don't specify the subtable as Linked it will run just fine)

Knowing this I am able to find other ways to solve my problem, but if you have any explanation on this behavior I would be interested in hearing it

Regards,

Helge

Jeff_Perkinson · Answer

Can you provide some more context for the New Table() statement?

For example, if you reuse the JSL variable dt then there is no longer a reference to the invisible table and JMP will close it.

dt=New Table("Invisible table", invisible);

dt=.;

So, we need to see some more of your JSL to help pin point what might be going on.

-Jeff