cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 
  • Learn how to build custom Python data connectors and further customize JMP’s Data Connector Framework with the Python Data Connector Demo, available now in the JMP Marketplace!
  • See how to create experiments to support product design and ID useful product features. Register for June 12 webinar, 2pm US Eastern Time.

Discussions

Solve problems, and share tips and tricks with other JMP users.
Choose Language Hide Translation Bar
mwechtal
Level III

Determining if a column exists

I have a JMP script that creates a new column with a formula in it. I'm trying to find out how to detect if the column already exists so that I can skip creating it, and avoid generating extra columns. I'm sure it's there, but I'm not finding it in the literature that I have.

Thanks.

Mike

10 REPLIES 10
wiebepo
Level III

Re: Determining if a column exists

PMroz,

Let me start by confirming that the code you wrote worked for me as well, and the explaination I wrote is not consistent with JMP 9 or 10 behavior.

After reading your reply, I also tried several different combinations of contains, and if statements with lists, string, and numbers in JMP 9 and 10. Although my attempts were not exhaustive, all of my results are consistent with yours. Initially, when I read your first post I recalled some troubleshooting that I had perform years prior where I had adopted the the use of contains()>0. I am unable to recreate the scenario; however, I did find the following information in the JMP scripting guide. It details using contains with >0, which may be appropriate for their example, but does not explicitly state that it is or is not required.

Page 136 of the JMP scripting guide version 10:

"To assess whether an item is in a list, use Loc() and Contains() with >0. A returned value of zero

means that the item is not in the list. A returned value of 1 means that the item is in the list at least once."

...

"Find out if the number 5 exists in the numList:

NRow(Loc(numList, 5)) >0;

0

Contains(numList, 5) >0;

0"

Hope this helps.

Recommended Articles