# MATLAB: Error in while command

MATLABwhile

hi
i want to run following loop till conditions are met. but unfortunately when i execute the program then following error occurs. even line of error is also not mention where error exist. kindly help me.
while sqrt(((target(1,1)-p(1,1)).^2)+((target(1,2)-p(1,2)).^2))>0.1
"Subscript indices must either be real positive integers or logicals."

#### Best Answer

• That could happen if you accidentally defined a variable named "sqrt".
Another common problem is using "i" (lower-case I) as a subscript in a location where "i" has not been assigned a numeric value. "i" is pre-defined as sqrt(-1) so you do not get a message about "i" being undefined if you do that. "j" has exactly the same issue.