| SQR( ) | Return Square Root | 
SQR(num[,ERR=stmtref])
  
Where:
| num | Value whose square root is to be returned. It must be a positive number. Numeric expression. | 
| stmtref | Program line number or statement label to which to transfer control. | 
Numeric, square root of given value.
The SQR( ) function returns the square root of the number provided, rounded to current PRECISION. If you use an invalid value (e.g. a negative value such as SQR(-2.345)), PxPlus returns an Error #40: Divide check or numeric overflow.
0010 input "Length of one side: ",A
 0020 if A<=0 then goto 0010
 0030 input "Length of other : ",B
 0040 if B<=0 then goto 0030
 0050 print "Hypotenuse is : ",sqr(A*A+B*B,err=*next)
 0060 print "DONE"; stop
 ->run
 Length of one side: 2.3
 Length of other: 1.65
 Hypotenuse is: 2.83