ABS (The GNU Fortran Compiler)

### 8.3 `ABS` — Absolute value ¶

Synopsis:

  `RESULT = ABS(A)`

Description:

  `ABS(A)` computes the absolute value of `A`.

Class:

  Elemental function

Arguments:

  A | The type of the argument shall be an `INTEGER`, `REAL`, or `COMPLEX`.

Return value:

  The return value is of the same type and kind as the argument except the return value is `REAL` for a `COMPLEX` argument.

Example:

      program test_abs
        integer :: i = -1
        real :: x = -1.e0
        complex :: z = (-1.e0,0.e0)
        i = abs(i)
        x = abs(x)
        x = abs(z)
      end program test_abs

Specific names:

  Name | Argument | Return type | Standard
  --- | --- | --- | ---
  `ABS(A)` | `REAL(4) A` | `REAL(4)` | Fortran 77 and later
  `CABS(A)` | `COMPLEX(4) A` | `REAL(4)` | Fortran 77 and later
  `DABS(A)` | `REAL(8) A` | `REAL(8)` | Fortran 77 and later
  `IABS(A)` | `INTEGER(4) A` | `INTEGER(4)` | Fortran 77 and later
  `BABS(A)` | `INTEGER(1) A` | `INTEGER(1)` | GNU extension
  `IIABS(A)` | `INTEGER(2) A` | `INTEGER(2)` | GNU extension
  `JIABS(A)` | `INTEGER(4) A` | `INTEGER(4)` | GNU extension
  `KIABS(A)` | `INTEGER(8) A` | `INTEGER(8)` | GNU extension
  `ZABS(A)` | `COMPLEX(8) A` | `REAL(8)` | GNU extension
  `CDABS(A)` | `COMPLEX(8) A` | `REAL(8)` | GNU extension

Standard:

  Fortran 77 and later, has overloads that are GNU extensions