Fungsi dasar yang mendukung aritmatika kompleks di R, selain operator aritmatika +, -, *, /, dan ^.
complex(length.out = 0, real = numeric(), imaginary = numeric(),
modulus = 1, argument = 0)
as.complex(x, …)
is.complex(x)<p></p><p>Re(z)
Im(z)
Mod(z)
Arg(z)
Conj(z)</p>| Parameter | Deskripsi |
|---|---|
length.out |
numeric. Desired length of the output vector, inputs being recycled as needed. |
real |
numeric vector. |
imaginary |
numeric vector. |
modulus |
numeric vector. |
argument |
numeric vector. |
x |
an object, probably of mode complex. |
z |
an object of mode complex, or one of a class for which a methods has been defined. |
… |
further arguments passed to or from other methods. |
# NOT RUN {
require(graphics)
0i ^ (-3:3)
matrix(1i^ (-6:5), nrow = 4) #- all columns are the same
0 ^ 1i # a complex NaN
## create a complex normal vector
z <- complex(real = stats::rnorm(100), imaginary = stats::rnorm(100))
## or also (less efficiently):
z2 <- 1:2 + 1i*(8:9)
## The Arg(.) is an angle:
zz <- (rep(1:4, len = 9) + 1i*(9:1))/10
zz.shift <- complex(modulus = Mod(zz), argument = Arg(zz) + pi)
plot(zz, xlim = c(-1,1), ylim = c(-1,1), col = "red", asp = 1,
main = expression(paste("Rotation by "," ", pi == 180^o)))
abline(h = 0, v = 0, col = "blue", lty = 3)
points(zz.shift, col = "orange")
showC <- function(z) noquote(sprintf("(R = %g, I = %g)", Re(z), Im(z)))
## The exact result of this *depends* on the platform, compiler, math-library:
(NpNA <- NaN + NA_complex_) ; str(NpNA) # *behaves* as 'cplx NA' ..
stopifnot(is.na(NpNA), is.na(NA_complex_), is.na(Re(NA_complex_)), is.na(Im(NA_complex_)))
showC(NpNA)# but not always is {shows '(R = NaN, I = NA)' on some platforms}
## and this is not TRUE everywhere:
identical(NpNA, NA_complex_)
showC(NA_complex_) # always == (R = NA, I = NA)
# }