Dear list members,

I know my post is a consequence of my very modest programming skills, however, I think, others users might encounter this problem as well.

I was trying to set up an if-command:

if [condtion 1] = True and [condition 2] = True than

do stuff

endif

In the first place, I used ‘and’ literally – I have to admit, that my first experience with if-conditions are from Excel-VBA.

This of course produced an error-message.

It took me while to figure out the solution. I remembered an R-tutorial which dealt with Boolean operators when I read the following post:

And most likely, my fault was to use the wrong operator ‘and’ instead of ‘&&’.

Maybe I have missed it in the user guide, but it might be helpful, to put in a table that deals with logical operators

&&, !, ||,etc. like

true && true is true

!true && false is true

Maybe this is clear to anyone else, than you can of course disregard my post.

Best regards

Jan