Is it possible that you previously evaluated a command defining
var as a string? For example,
var = 'x1'
If you did that (and even if you erased that line), then the line
x1 = var('x1'); x1
would produce the exact error that you are seeing.
Try restarting the worksheet (using the orange "Restart" button at the top), this will reset all names, and now the code should execute as expected.
Asked: 2014-07-30 11:23:23 -0500
Seen: 83 times
Last updated: Aug 05 '14