| curve {base} | R Documentation |
Draws a curve corresponding to the given function or expression (in
x) over the interval [from,to].
curve(expr, from, to, n = 101, add = FALSE, type = "l",
ylab = NULL, log = NULL, ...)
plot.function(fn, from = 0, to = 1, n = 101, ...)
expr |
an expression written as a function of x, or
alternatively a function which will be plotted. |
fn |
a `vectorizing' numeric R function. |
from,to |
the range over which the function will be plotted. |
n |
integer; the number of x values at which to evaluate. |
add |
logical; if TRUE add to already existing plot. |
... |
graphical parameters can also be specified as arguments.
plot.function passes all these to curve. |
The evaluation of expr is at n points equally spaced
over the range [from, to]. The points determined in this way
are then joined with straight lines. fn(x) or expr
(with x inside) must return a numeric of the same length as
x.
This used to be a quick hack which seems to serve a useful purpose, but can give bad results for functions which are not smooth.
NULL. For ``expensive'' expressions, you should use
smarter tools.
splinefun for spline interpolation, lines.
par(mfrow=c(2,2))
curve(x^3-3*x, -2, 2)
curve(x^2-2, add = TRUE, col = "violet")
curve(sin, -pi, 3*pi)
plot(cos)
chippy <- function(x) sin(cos(x)*exp(-x/2))
curve(chippy, -8, 7, n=2001)
for(ll in c("","x","y","xy"))
curve(log(1+x), 1,100, log=ll, sub=paste("log=",ll))