Error while evaluating UIControl Callback.

[Tanya Chhabra]

Hello Dr Thielicke, 

I am trying to extract data along a polyline and am met with the following error and am unable to fix it. I would be extremely grateful for any leads on how to go about it.

Unable to perform assignment because the left and right sides have a different number of elements.

Error in PIVlab_GUI>draw_stuff_Callback (line 7961)
xposition(n)=xi;
 
Error while evaluating UIControl Callback.

Best, 

Tanya