complex
Complex Valued Objects
Description
The complex and as.complex functions create vectors of complex numbers.
Usage
complex(length.out = 0L, real = numeric(), imaginary = numeric(),
modulus = 1, argument = 0)
is.complex(x)
as.complex(x, ...)
Arguments
| length |
length of the returned object.
|
| real |
vector of real parts for use in the construction of the return value.
|
| imaginary |
vector of imaginary parts for use in the construction of the return value.
|
| modulus |
vector of moduli for use in the construction of the return value.
|
| argument |
vector of arguments for use in the construction of the return value.
|
| x |
any object.
|
| ... |
additional arguments.
|
Details
The "+" within the rectangular representation of a complex number has the
usual precedence.
The as.complex function is generic but
currently there are no methods written for it.
Value
| complex | returns a simple object (that is, a vector) of mode "complex".
If real and/or imaginary are specified, the real and
imaginary parts of the result are set from them, using the defaults
if necessary.
If modulus and/or argument are specified, the modulus and
argument of the result are set from them, using the defaults
if necessary. real and imaginary are ignored in this case. |
| is.complex | returns TRUE if x is of mode "complex". Otherwise, returns
FALSE.
Its behavior is unaffected by any attributes of x; for example, x could
be a complex array. |
| as.complex | returns x if x is a simple object of mode "complex". Otherwise,
it returns a complex object of the same length as x and with data resulting
from coercing the elements of x to mode "complex".
Attributes are deleted. |
See Also
Complex
(describes the functions that do basic manipulations of complex),
numbers.
Examples
complex(real=3, imag=4) == 3+4i
complex(mod=2, arg=1.5*pi) - (-2i) # almost equal
abs(3+4i)
log(complex(arg=seq(0, pi, len=5))) / pi
log(-.1) # NaN, because -.1 is numeric, not complex
log(-.1 + 0i) # complex(re=-log(10), im=pi)
sqrt(as.complex(-4:4))
Re(sqrt(as.complex(-4:4)))
x <- -7:8
fft(sin(x*2.5*pi) + 1/(1+x^2))[1:(length(x)/2)]