The SQRT function computes the square root of X.


To find the square root of 145 and store the result in variable S, enter:

S = SQRT(145)


Result = SQRT(X)

Return Value

Returns the square root of X.



The value for which the square root is desired. If X is double-precision floating-point or complex, the result is of the same type. All other types are converted to single-precision floating-point and yield floating-point results. When applied to complex numbers, z = x+iy:

The ambiguous sign is taken to be the same as the sign of y. The result has the same structure as X.


Thread Pool Keywords

This routine is written to make use of IDL’s thread pool, which can increase execution speed on systems with multiple CPUs. The values stored in the !CPU system variable control whether IDL uses the thread pool for a given computation. In addition, you can use the thread pool keywords TPOOL_MAX_ELTS, TPOOL_MIN_ELTS, and TPOOL_NOTHREAD to override the defaults established by !CPU for a single invocation of this routine. See Thread Pool Keywords for details.

Version History



See Also

Using Exponentiation