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std.complex.Complex/complex - multiple declarations

Function complex

Helper function that returns a complex number with the specified real and imaginary parts.


auto complex(R)(
  R re
) pure nothrow @nogc @safe
if (is(R : double));

auto complex(R, I)(
  R re,
  I im
) pure nothrow @nogc @safe
if (is(R : double) && is(I : double));


R (template parameter) type of real part of complex number
I (template parameter) type of imaginary part of complex number
re real part of complex number to be constructed
im (optional) imaginary part of complex number, 0 if omitted.


Complex instance with real and imaginary parts set to the values provided as input. If neither re nor im are floating-point numbers, the return type will be Complex!double. Otherwise, the return type is deduced using std.traits.CommonType!(R, I).


auto a = complex(1.0);
static assert(is(typeof(a) == Complex!double));
writeln(; // 1.0
writeln(; // 0.0

auto b = complex(2.0L);
static assert(is(typeof(b) == Complex!real));
writeln(; // 2.0L
writeln(; // 0.0L

auto c = complex(1.0, 2.0);
static assert(is(typeof(c) == Complex!double));
writeln(; // 1.0
writeln(; // 2.0

auto d = complex(3.0, 4.0L);
static assert(is(typeof(d) == Complex!real));
writeln(; // 3.0
writeln(; // 4.0L

auto e = complex(1);
static assert(is(typeof(e) == Complex!double));
writeln(; // 1
writeln(; // 0

auto f = complex(1L, 2);
static assert(is(typeof(f) == Complex!double));
writeln(; // 1L
writeln(; // 2

auto g = complex(3, 4.0L);
static assert(is(typeof(g) == Complex!real));
writeln(; // 3
writeln(; // 4.0L

Struct Complex

A complex number parametrised by a type T, which must be either float, double or real.

Template arguments

struct Complex(T)
if (isFloatingPoint!T);


Name Description
this Construct a complex number with the specified real and imaginary parts. In the case where a single argument is passed that is not complex, the imaginary part of the result will be zero.


Name Type Description
im T The imaginary part of the number.
re T The real part of the number.


Name Description
toString Converts the complex number to a string representation.


Lars Tandle Kyllingstad, Don Clugston


Boost License 1.0