SQR function computes the square root of its argument. This is -- as usual in computing -- the nonnegative branch. So for any x>=0,
(to use BASIC syntax
SQR(x) will cause a run time error.
Perversely, Pascal defines
sqr(x) to compute the square of x. So
for any x
This gave many computer children of the 80s great pain when trying to continue to program in both BASIC and Pascal.