AIMAG

インテル® Fortran コンパイラー 14.0 ユーザー・リファレンス・ガイド

Elemental Intrinsic Function (Generic): Returns the imaginary part of a complex number. This function can also be specified as IMAG.

result = AIMAG (z)

z	(Input) Must be of type complex.

結果

The result type is real with the same kind parameter as z. If z has the value (x, y), the result has the value y.

Specific Name	Argument Type	Result Type
AIMAG ¹	COMPLEX(4)	REAL(4)
DIMAG	COMPLEX(8)	REAL(8)
QIMAG	COMPLEX(16)	REAL(16)
¹The setting of compiler options specifying real size can affect AIMAG.

To return the real part of complex numbers, use REAL.

AIMAG ((4.0, 5.0)) has the value 5.0.

The program AIMAG.F90 applies the quadratic formula to a polynomial and allows for complex results:

REAL a, b, c

COMPLEX ans1, ans2, d

WRITE ( *, 100)

100 FORMAT ('  Enter A, b, and c of the  ',   &

                           'polynomial ax**2 + bx + c:  '\)

READ (*, *) a, b, c

d = CSQRT (CMPLX (b**2 - 4.0*a*c))  ! d is either:

                                    !  0.0 + i root, or

                                    !  root + i 0.0

ans1 = (-b + d) / (2.0 * a)

ans2 = (-b + d) / (2.0 * a)

WRITE (*, 200)

200 FORMAT (/ '  The roots are:'  /)

WRITE (*, 300) REAL(ans1), AIMAG(ans1), &

                   REAL(ans2), AIMAG(ans2)

300 FORMAT (' X = ', F10.5, ' + i', F10.5)

END