intrinsic.texi

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@item @emph{Class}:
elemental function

@item @emph{Syntax}:
@code{X = AINT(X)} 
@code{X = AINT(X, KIND)}

@item @emph{Arguments}:
@multitable @columnfractions .15 .80
@item @var{X}    @tab The type of the argument shall be @code{REAL(*)}.
@item @var{KIND} @tab (Optional) @var{KIND} shall be a scalar integer
initialization expression.
@end multitable

@item @emph{Return value}:
The return value is of type real with the kind type parameter of the
argument if the optional @var{KIND} is absent; otherwise, the kind
type parameter will be given by @var{KIND}.  If the magnitude of 
@var{X} is less than one, then @code{AINT(X)} returns zero.  If the
magnitude is equal to or greater than one, then it returns the largest
whole number that does not exceed its magnitude.  The sign is the same
as the sign of @var{X}. 

@item @emph{Example}:
@smallexample
program test_aint
  real(4) x4
  real(8) x8
  x4 = 1.234E0_4
  x8 = 4.321_8
  print *, aint(x4), dint(x8)
  x8 = aint(x4,8)
end program test_aint
@end smallexample

@item @emph{Specific names}:
@multitable @columnfractions .24 .24 .24 .24
@item Name           @tab Argument         @tab Return type      @tab Option
@item @code{DINT(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)}   @tab f95, gnu
@end multitable
@end table



@node ALARM
@section @code{ALARM} --- Execute a routine after a given delay
@findex @code{ALARM} intrinsic

@table @asis
@item @emph{Description}:
@code{ALARM(SECONDS [, STATUS])} causes external subroutine @var{HANDLER}
to be executed after a delay of @var{SECONDS} by using @code{alarm(1)} to
set up a signal and @code{signal(2)} to catch it. If @var{STATUS} is
supplied, it will be returned with the number of seconds remaining until
any previously scheduled alarm was due to be delivered, or zero if there
was no previously scheduled alarm.

@item @emph{Option}:
gnu

@item @emph{Class}:
subroutine

@item @emph{Syntax}:
@code{CALL ALARM(SECONDS, HANDLER)} 
@code{CALL ALARM(SECONDS, HANDLER, STATUS)}

@item @emph{Arguments}:
@multitable @columnfractions .15 .80
@item @var{SECONDS} @tab The type of the argument shall be a scalar
@code{INTEGER}. It is @code{INTENT(IN)}.
@item @var{HANDLER} @tab Signal handler (@code{INTEGER FUNCTION} or
@code{SUBROUTINE}) or dummy/global @code{INTEGER} scalar.
@code{INTEGER}. It is @code{INTENT(IN)}.
@item @var{STATUS}  @tab (Optional) @var{STATUS} shall be a scalar
@code{INTEGER} variable. It is @code{INTENT(OUT)}.
@end multitable

@item @emph{Example}:
@smallexample
program test_alarm
  external handler_print
  integer i
  call alarm (3, handler_print, i)
  print *, i
  call sleep(10)
end program test_alarm
@end smallexample
This will cause the external routine @var{handler_print} to be called
after 3 seconds.
@end table



@node ALL
@section @code{ALL} --- All values in @var{MASK} along @var{DIM} are true 
@findex @code{ALL} intrinsic
@cindex true values

@table @asis
@item @emph{Description}:
@code{ALL(MASK [, DIM])} determines if all the values are true in @var{MASK}
in the array along dimension @var{DIM}.

@item @emph{Option}:
f95, gnu

@item @emph{Class}:
transformational function

@item @emph{Syntax}:
@code{L = ALL(MASK)} 
@code{L = ALL(MASK, DIM)}

@item @emph{Arguments}:
@multitable @columnfractions .15 .80
@item @var{MASK} @tab The type of the argument shall be @code{LOGICAL(*)} and
it shall not be scalar.
@item @var{DIM}  @tab (Optional) @var{DIM} shall be a scalar integer
with a value that lies between one and the rank of @var{MASK}.
@end multitable

@item @emph{Return value}:
@code{ALL(MASK)} returns a scalar value of type @code{LOGICAL(*)} where
the kind type parameter is the same as the kind type parameter of
@var{MASK}.  If @var{DIM} is present, then @code{ALL(MASK, DIM)} returns
an array with the rank of @var{MASK} minus 1.  The shape is determined from
the shape of @var{MASK} where the @var{DIM} dimension is elided. 

@table @asis
@item (A)
@code{ALL(MASK)} is true if all elements of @var{MASK} are true.
It also is true if @var{MASK} has zero size; otherwise, it is false.
@item (B)
If the rank of @var{MASK} is one, then @code{ALL(MASK,DIM)} is equivalent
to @code{ALL(MASK)}.  If the rank is greater than one, then @code{ALL(MASK,DIM)}
is determined by applying @code{ALL} to the array sections.
@end table

@item @emph{Example}:
@smallexample
program test_all
  logical l
  l = all((/.true., .true., .true./))
  print *, l
  call section
  contains
    subroutine section
      integer a(2,3), b(2,3)
      a = 1
      b = 1
      b(2,2) = 2
      print *, all(a .eq. b, 1)
      print *, all(a .eq. b, 2)
    end subroutine section
end program test_all
@end smallexample
@end table



@node ALLOCATED
@section @code{ALLOCATED} --- Status of an allocatable entity
@findex @code{ALLOCATED} intrinsic
@cindex allocation status

@table @asis
@item @emph{Description}:
@code{ALLOCATED(X)} checks the status of whether @var{X} is allocated.

@item @emph{Option}:
f95, gnu

@item @emph{Class}:
inquiry function

@item @emph{Syntax}:
@code{L = ALLOCATED(X)}

@item @emph{Arguments}:
@multitable @columnfractions .15 .80
@item @var{X}    @tab The argument shall be an @code{ALLOCATABLE} array.
@end multitable

@item @emph{Return value}:
The return value is a scalar @code{LOGICAL} with the default logical
kind type parameter.  If @var{X} is allocated, @code{ALLOCATED(X)}
is @code{.TRUE.}; otherwise, it returns the @code{.TRUE.} 

@item @emph{Example}:
@smallexample
program test_allocated
  integer :: i = 4
  real(4), allocatable :: x(:)
  if (allocated(x) .eqv. .false.) allocate(x(i)
end program test_allocated
@end smallexample
@end table



@node ANINT
@section @code{ANINT} --- Imaginary part of complex number  
@findex @code{ANINT} intrinsic
@findex @code{DNINT} intrinsic
@cindex whole number

@table @asis
@item @emph{Description}:
@code{ANINT(X [, KIND])} rounds its argument to the nearest whole number.

@item @emph{Option}:
f95, gnu

@item @emph{Class}:
elemental function

@item @emph{Syntax}:
@code{X = ANINT(X)}
@code{X = ANINT(X, KIND)}

@item @emph{Arguments}:
@multitable @columnfractions .15 .80
@item @var{X}    @tab The type of the argument shall be @code{REAL(*)}.
@item @var{KIND} @tab (Optional) @var{KIND} shall be a scalar integer
initialization expression.
@end multitable

@item @emph{Return value}:
The return value is of type real with the kind type parameter of the
argument if the optional @var{KIND} is absent; otherwise, the kind
type parameter will be given by @var{KIND}.  If @var{X} is greater than
zero, then @code{ANINT(X)} returns @code{AINT(X+0.5)}.  If @var{X} is
less than or equal to zero, then return @code{AINT(X-0.5)}.

@item @emph{Example}:
@smallexample
program test_anint
  real(4) x4
  real(8) x8
  x4 = 1.234E0_4
  x8 = 4.321_8
  print *, anint(x4), dnint(x8)
  x8 = anint(x4,8)
end program test_anint
@end smallexample

@item @emph{Specific names}:
@multitable @columnfractions .24 .24 .24 .24
@item Name            @tab Argument         @tab Return type      @tab Option
@item @code{DNINT(X)} @tab @code{REAL(8) X} @tab @code{REAL(8)}   @tab f95, gnu
@end multitable
@end table



@node ANY
@section @code{ANY} --- Any value in @var{MASK} along @var{DIM} is true 
@findex @code{ANY} intrinsic
@cindex true values

@table @asis
@item @emph{Description}:
@code{ANY(MASK [, DIM])} determines if any of the values in the logical array
@var{MASK} along dimension @var{DIM} are @code{.TRUE.}.

@item @emph{Option}:
f95, gnu

@item @emph{Class}:
transformational function

@item @emph{Syntax}:
@code{L = ANY(MASK)} 
@code{L = ANY(MASK, DIM)}

@item @emph{Arguments}:
@multitable @columnfractions .15 .80
@item @var{MASK} @tab The type of the argument shall be @code{LOGICAL(*)} and
it shall not be scalar.
@item @var{DIM}  @tab (Optional) @var{DIM} shall be a scalar integer
with a value that lies between one and the rank of @var{MASK}.
@end multitable

@item @emph{Return value}:
@code{ANY(MASK)} returns a scalar value of type @code{LOGICAL(*)} where
the kind type parameter is the same as the kind type parameter of
@var{MASK}.  If @var{DIM} is present, then @code{ANY(MASK, DIM)} returns
an array with the rank of @var{MASK} minus 1.  The shape is determined from
the shape of @var{MASK} where the @var{DIM} dimension is elided. 

@table @asis
@item (A)
@code{ANY(MASK)} is true if any element of @var{MASK} is true;
otherwise, it is false.  It also is false if @var{MASK} has zero size.
@item (B)
If the rank of @var{MASK} is one, then @code{ANY(MASK,DIM)} is equivalent
to @code{ANY(MASK)}.  If the rank is greater than one, then @code{ANY(MASK,DIM)}
is determined by applying @code{ANY} to the array sections.
@end table

@item @emph{Example}:
@smallexample
program test_any
  logical l
  l = any((/.true., .true., .true./))
  print *, l
  call section
  contains
    subroutine section
      integer a(2,3), b(2,3)
      a = 1
      b = 1
      b(2,2) = 2
      print *, any(a .eq. b, 1)
      print *, any(a .eq. b, 2)
    end subroutine section
end program test_any
@end smallexample
@end table



@node ASIN
@section @code{ASIN} --- Arcsine function 
@findex @code{ASIN} intrinsic
@findex @code{DASIN} intrinsic
@cindex arcsine

@table @asis
@item @emph{Description}:
@code{ASIN(X)} computes the arcsine of its @var{X}.

@item @emph{Option}:
f95, gnu

@item @emph{Class}:
elemental function

@item @emph{Syntax}:
@code{X = ASIN(X)}

@item @emph{Arguments}:
@multitable @columnfractions .15 .80
@item @var{X} @tab The type shall be @code{REAL(*)}, and a magnitude that is
less than one.
@end multitable

@item @emph{Return value}:
The return value is of type @code{REAL(*)} and it lies in the
range @math{-\pi / 2 \leq \arccos (x) \leq \pi / 2}.  The kind type
parameter is the same as @var{X}.

@item @emph{Example}:
@smallexample
program test_asin
  real(8) :: x = 0.866_8
  x = asin(x)
end program test_asin
@end smallexample

@item @emph{Specific names}:
@multitable @columnfractions .24 .24 .24 .24
@item Name            @tab Argument          @tab Return type       @tab Option
@item @code{DASIN(X)} @tab @code{REAL(8) X}  @tab @code{REAL(8)}    @tab f95, gnu
@end multitable
@end table



@node ASSOCIATED
@section @code{ASSOCIATED} --- Status of a pointer or pointer/target pair 
@findex @code{ASSOCIATED} intrinsic
@cindex pointer status

@table @asis
@item @emph{Description}:
@code{ASSOCIATED(PTR [, TGT])} determines the status of the pointer @var{PTR}
or if @var{PTR} is associated with the target @var{TGT}.

@item @emph{Option}:
f95, gnu

@item @emph{Class}:
inquiry function

@item @emph{Syntax}:
@code{L = ASSOCIATED(PTR)} 
@code{L = ASSOCIATED(PTR [, TGT])}

@item @emph{Arguments}:
@multitable @columnfractions .15 .80
@item @var{PTR} @tab @var{PTR} shall have the @code{POINTER} attribute and
it can be of any type.
@item @var{TGT} @tab (Optional) @var{TGT} shall be a @code{POINTER} or
a @code{TARGET}.  It must have the same type, kind type parameter, and
array rank as @var{PTR}.
@end multitable
The status of neither @var{PTR} nor @var{TGT} can be undefined.

@item @emph{Return value}:
@code{ASSOCIATED(PTR)} returns a scalar value of type @code{LOGICAL(4)}.
There are several cases:
@table @asis
@item (A) If the optional @var{TGT} is not present, then @code{ASSOCIATED(PTR)}
is true if @var{PTR} is associated with a target; otherwise, it returns false.
@item (B) If @var{TGT} is present and a scalar target, the result is true if
@var{TGT}
is not a 0 sized storage sequence and the target associated with @var{PTR}
occupies the same storage units.  If @var{PTR} is disassociated, then the 
result is false.
@item (C) If @var{TGT} is present and an array target, the result is true if
@var{TGT} and @var{PTR} have the same shape, are not 0 sized arrays, are
arrays whose elements are not 0 sized storage sequences, and @var{TGT} and
@var{PTR} occupy the same storage units in array element order.
As in case(B), the result is false, if @var{PTR} is disassociated.
@item (D) If @var{TGT} is present and an scalar pointer, the result is true if
target associated with @var{PTR} and the target associated with @var{TGT}
are not 0 sized storage sequences and occupy the same storage units.
The result is false, if either @var{TGT} or @var{PTR} is disassociated.
@item (E) If @var{TGT} is present and an array pointer, the result is true if
target associated with @var{PTR} and the target associated with @var{TGT}
have the same shape, are not 0 sized arrays, are arrays whose elements are
not 0 sized storage sequences, and @var{TGT} and @var{PTR} occupy the same
storage units in array element order.
The result is false, if either @var{TGT} or @var{PTR} is disassociated.
@end table

@item @emph{Example}:
@smallexample
program test_associated
   implicit none
   real, target  :: tgt(2) = (/1., 2./)
   real, pointer :: ptr(:)
   ptr => tgt
   if (associated(ptr)     .eqv. .false.) call abort
   if (associated(ptr,tgt) .eqv. .false.) call abort
end program test_associated
@end smallexample
@end table



@node ATAN
@section @code{ATAN} --- Arctangent function 
@findex @code{ATAN} intrinsic
@findex @code{DATAN} intrinsic
@cindex arctangent

@table @asis
@item @emph{Description}:
@code{ATAN(X)} computes the arctangent of @var{X}.

@item @emph{Option}:
f95, gnu

@item @emph{Class}:
elemental function

@item @emph{Syntax}:
@code{X = ATAN(X)}

@item @emph{Arguments}:
@multitable @columnfractions .15 .80
@item @var{X} @tab The type shall be @code{REAL(*)}.
@end multitable

@item @emph{Return value}:
The return value is of type @code{REAL(*)} and it lies in the
range @math{ - \pi / 2 \leq \arcsin (x) \leq \pi / 2}.

@item @emph{Example}:
@smallexample
program test_atan
  real(8) :: x = 2.866_8
  x = atan(x)
end program test_atan