Fortran Wiki
mod

Description

mod(a,p) computes the remainder of the division of a by p.

Standard

FORTRAN 77 and later

Class

Elemental function

Syntax

result = mod(a, p)

Arguments

• a - Shall be a scalar of type integer or real.
• p - Shall be a scalar of the same type and kind as a and not equal to zero.

Return value

The return value is the result of a - (int(a/p) * p). The type and kind of the return value is the same as that of the arguments. The returned value has the same sign as a and a magnitude less than the magnitude of p.

Example

program test_mod
  print *, mod(17,3)         ! yields 2
  print *, mod(17.5,5.5)     ! yields 1.0
  print *, mod(17.5d0,5.5)   ! yields 1.0d0
  print *, mod(17.5,5.5d0)   ! yields 1.0d0

  print *, mod(-17,3)        ! yields -2
  print *, mod(-17.5,5.5)    ! yields -1.0
  print *, mod(-17.5d0,5.5)  ! yields -1.0d0
  print *, mod(-17.5,5.5d0)  ! yields -1.0d0

  print *, mod(17,-3)        ! yields 2
  print *, mod(17.5,-5.5)    ! yields 1.0
  print *, mod(17.5d0,-5.5)  ! yields 1.0d0
  print *, mod(17.5,-5.5d0)  ! yields 1.0d0
end program test_mod

See also

modulo