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.TI F77/COMPLEX "Sep. 4, 1985"
Complex and Double Complex Constants, Variables and Intrinsic Functions

Declare single precision complex variables as type 'complex' or 'complex*8';
declare double precision complex variables as 'double complex' or 'complex*16'. 

Here is an example illustrating the use of single precision complex
variables and constants:

.nf
		implicit complex (c)
		data x1/8.5/, x2/9.2/
		
	c		create c1 from a complex constant
		c1 = (1.1,2.1)
	c		create c2 from two real variables
		c2 = cmplx( x1, x2 )
	
	c		take complex square root of c1 using
	c			the generic function name
		c3 = sqrt(c1)
	
	c		get the real part of c3
		xreal1 = c3
		xreal2 = real(c3)
	c		get imaginary part, aimag() would also work
		ximag = imag( c3 )
	c		find the conjugate of c3
		c4 = conjg(c3)
	
		print *, c1,c2,c3,c4,x1,x2,xreal1,xreal2,ximag
		end
.fi

The same example in double precision:

.nf
		implicit double complex (z)
		implicit double precision (d)
		data d1/8.5d0/, d2/9.2d0/
		
		z1 = (1.1d0,2.1d0)
		z2 = dcmplx( d1, d2 )
		z3 = sqrt(z1)
	c		get the real part, dreal() would also work
		dxreal1 = z3
		dxreal2 = dble(z3)
	c		get the imaginary part, dimag() would also work
		dximag = imag( z3 )
	c		find the conjugate
		z4 = conjg(z3)
	
		print *, z1,z2,z3,z4,d1,d2,dxreal1,dxreal2,dximag
		end
.fi

To create a complex value from real variables, use 'cmplx()'.  To
create a double complex value from double precision variables, use 'dcmplx()'.
The generic function names, that work with both complex
and double complex, are:

.nf
     imag(), conjg(), sqrt(), abs(), exp(), log(), sin(), cos()
.fi

If you declare the function to be external and pass the function name
to a procedure, you must use the specific function name.  For single
precision, they are:

.nf
    aimag(), conjg(),csqrt(),cabs(),cexp(),clog(),csin(),ccos()
.fi

and for double precision, they are:

.nf
    dimag(),dconjg(),zsqrt(),zabs(),zexp(),zlog(),zsin(),zcos()
.fi

For compatibility with other vendors compilers, the last six
specific functions may also be referred to as:

.nf
    cdsqrt(),cdabs(),cdexp(),cdlog(),cdsin(),cdcos()
.fi

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