Intel® Fortran Compiler Classic and Intel® Fortran Compiler Developer Guide and Reference

ID 767251
Date 3/22/2024
Public

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Document Table of Contents

SQRT

Elemental Intrinsic Function (Generic): Produces the square root of its argument.

result = SQRT (x)

x

(Input) must be of type real or complex. If x is type real, its value must be greater than or equal to zero.

Results

The result type and kind are the same as x. The result has a value equal to the square root of x.

A result of type complex is the principal value, with the real part greater than or equal to zero.

When the real part of the result is zero, the imaginary part of the result has the same sign as the imaginary part of x , even if the imaginary part of x is a negative real zero.

Specific Name

Argument Type

Result Type

SQRT

REAL(4)

REAL(4)

DSQRT

REAL(8)

REAL(8)

QSQRT

REAL(16)

REAL(16)

CSQRT 1

COMPLEX(4)

COMPLEX(4)

CDSQRT2

COMPLEX(8)

COMPLEX(8)

CQSQRT

COMPLEX(16)

COMPLEX(16)

1The setting of compiler options specifying real size can affect CSQRT.

2This function can also be specified as ZSQRT.

Example

SQRT (16.0) has the value 4.0.

SQRT (3.0) has the value 1.732051.

The following shows another example:

 ! Calculate the hypotenuse of a right triangle
 ! from the lengths of the other two sides.
 REAL sidea, sideb, hyp
 sidea = 3.0
 sideb = 4.0
 hyp = SQRT (sidea**2 + sideb**2)
 WRITE (*, 100) hyp
 100 FORMAT (/ ' The hypotenuse is ', F10.3)
 END