Fortran 90 数値関数

• aimag
複素数の虚数部を求める

     y = aimag(z)

     complex,intent(in) :: z
     real               :: y = Im(z)
     

• aint, anint
aint : 小数点以下を切り捨てる (ie int)
anint: 小数点以下を四捨五入する (ie nint)

     y = aint(a [,kind])

     real,intent(in)    :: a
     integer,intent(in) :: kind ! default is same of a
     real(kind=kind)    :: y    ! a-1 < y <= a

     i = anint(a [,kind])

     real,intetn(in)    :: a
     integer,intent(in) :: kind ! default is same of a
     real(kind=kind)    :: y    ! a - 0.5 < y <= a + 0.5
     

• ceiling, floor
ceiling: 引数以上で最小の整数を求める
floor : 引数以下で最大の整数を求める

     i = ceiling(a)

     real,intent(in) :: a
     integer         :: i ! a <= i < a+1

     i = floor(a)

     real,intent(in) :: a
     integer         :: i ! a-1 < i <= a
     

• cmplx
複素数に変換する

     z = cmplx(x [,y] [,kind])

     integer,intent(in) :: x
     integer,intent(in) :: y
     integer,intent(in) :: kind ! default is same of x
     complex(kind=kind) :: z = x + iy

     integer,intent(in) :: x
     real,intent(in)    :: y
     integer,intent(in) :: kind ! default is same of x
     complex(kind=kind) :: z = x + iy

     real,intent(in)    :: x
     integer,intent(in) :: y
     integer,intent(in) :: kind ! default is same of x
     complex(kind=kind) :: z = x + iy

     real,intent(in)    :: x
     real,intent(in)    :: y
     integer,intent(in) :: kind ! default is same of x
     complex(kind=kind) :: z = x + iy

     complex,intent(in) :: x
     integer,intent(in) :: kind ! default is same of x
     complex(kind=kind) :: z = x
     

• conjg
共役複素数を求める

     y = conjg(z)

     complex,intent(in) :: z
     complex            :: y = Re(z)-iIm(z)
     

• dble
倍精度実数型に変換する

     d = dble(a)

     real,intent(in) :: a
     real(kind=8)    :: d
     

• dim
第一引数が第二引数よりもどれだけ大きいかを求める

     z = dim(x,y)

     integer,intent(in) :: x, y
     integer            :: z = x-y (x > y)
                             = 0   (x < y)

     real,intent(in)    :: x, y
     real               :: z = x-y (x > y)
                             = 0   (x < y)
     

• dprod
倍精度実数型の積を計算する

     z = dprod(x,y)

     real(kind=4),intent(in) :: x, y
     reak(kind=8)            :: z = dble(x)*dble(y)
     

• kind
種別型パラメタ値を返す

     i = kind(x)

     integer,intent(in) :: x
     real,intent(in)    :: x
     complex,intent(in) :: x
     integer            :: i
     

• int, nint
int :小数点以下を切り捨てた整数を求める (ie aint)
nint:小数点以下を四捨五入した整数を求める (ie aint)

     i = int(a [,kind])

     integer,intent(in) :: a
     integer,intent(in) :: kind ! default is same of a
     inteter(kind=kind) :: i = a

     real,intent(in)    :: a
     integer,intent(in) :: kind ! default is same of a
     integer(kind=kind) :: i    ! a-1 < i <= a

     complex,intent(in) :: a
     integer,intent(in) :: kind ! default is same of a
     integer(kind=kind) :: i = int(real(a))

     i = nint(a [,kind])

     real,intent(in)    :: a
     integer,intent(in) :: kind ! default is same of a
     integer(kind=kind) :: i = int(anint(a))

     complex,intent(in) :: a
     integer,intent(in) :: kind ! default is same of a
     integer(kind=kind) :: i = int(anint(real(a)))
     

• max, min
max: 引数の中で最大値を求める
min: 引数の中で最小値を求める

     y = max(a1, a2 [,a3] [,a4] [,…])

     integer,intent(in) :: a1, a2, a3, a4, …
     integer            :: y ! y >= a1, a2, a3, a4, …

     real,intent(in)    :: a1, a2, a3, a4, …
     real               :: y ! y >= a1, a2, a3, a4, …
	       
     y = min(a1, a2 [,a3] [,a4] [,…])

     integer,intent(in) :: a1, a2, a3, a4, …
     integer            :: y ! y <= a1, a2, a3, a4, …

     real,intent(in)    :: a1, a2, a3, a4, …
     real               :: y ! y <= a1, a2, a3, a4, …
     

• real
実数型に変換する

      y = real(a [,kind])

      integer,intent(in) :: a
      integer,intent(in) :: kind ! default is same of a
      real(kind=kind)    :: y = 1.0*a

      real,intent(in)    :: a
      integer,intent(in) :: kind ! default is same of a
      real(kind=kind)    :: y = a

      complex,intent(in) :: a
      integer,intent(in) :: kind ! default is same of a
      real(kind=kind)    :: y = Re(a)
      

• selected_int_kind,selected_real_kind
selected_int_kind : 有効桁数p以上で精度が最小である種別パラメタを返す
selected_real_kind: 有効桁数p、指数範囲r以上で精度が最小である種別パラメタを返す


     kind = selected_int_kind(r)

     integer,intent(in) :: r
     integer            :: kind

     kind = selected_real_kind([p] [,r])

     integer,intent(in) :: p, r ! 少なくとも1つの引数は指定しなければならない
     integer            :: kind
     

• sign
第一引数の絶対値に第二引数の符合をつけたものを求める

     z = sign(a, b)

     integer,intent(in) :: a, b
     integer            :: z = abs(a) * b / abs(b)

     real,intent(in)    :: a, b
     real               :: z = abs(a) * b / abs(b)
     

• transfer
sourceと物理表現が同じであるmoldと同じ型の値を返す

     z = transfer(source, mold [,size])

     *,intent(in)       :: source or source(:)
     *,intent(in)       :: mold or mold(:)
     integer,intent(in) :: size

     *                  :: z or z(size) ! type is same of mold