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  \item{\dots}{potentially further arguments (required by the generic).}
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  \item{\dots}{potentially further arguments (required by the generic).}
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}
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}
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\description{
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\description{
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  Given the vectors \eqn{(x_1, \ldots, x_n)}{(x[1], \dots, x[n])} and
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  Given the vectors \eqn{(x_1, \ldots, x_n)}{(x[1], \dots, x[n])} and
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  \eqn{(y_0,y_1,\ldots, y_n)}{(y[0], y[1], \dots, y[n])} (one value
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  \eqn{(y_0,y_1,\ldots, y_n)}{(y[0], y[1], \dots, y[n])} (one value
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  more!), \code{stepfun(x,y,\dots)} returns an interpolating
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  more!), \code{stepfun(x, y, \dots)} returns an interpolating
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  \sQuote{step} function, say \code{fn}. I.e., \eqn{fn(t) =
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  \sQuote{step} function, say \code{fn}. I.e., \eqn{fn(t) =
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    c}\eqn{_i}{[i]} (constant) for \eqn{t \in (x_i, x_{i+1})}{t in (
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    c}\eqn{_i}{[i]} (constant) for \eqn{t \in (x_i, x_{i+1})}{t in (
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    x[i], x[i+1])} and at the abscissa values, if (by default)
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    x[i], x[i+1])} and at the abscissa values, if (by default)
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  \code{right = FALSE}, \eqn{fn(x_i) = y_i}{fn(x[i]) = y[i]} and for
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  \code{right = FALSE}, \eqn{fn(x_i) = y_i}{fn(x[i]) = y[i]} and for
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  \code{right = TRUE}, \eqn{fn(x_i) = y_{i-1}}{fn(x[i]) = y[i-1]}, for
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  \code{right = TRUE}, \eqn{fn(x_i) = y_{i-1}}{fn(x[i]) = y[i-1]}, for
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  step functions.
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  step functions.
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  \code{\link{approxfun}} and \code{\link{splinefun}}.
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  \code{\link{approxfun}} and \code{\link{splinefun}}.
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}
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}
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\examples{
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\examples{
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y0 <- c(1.,2.,4.,3.)
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y0 <- c(1., 2., 4., 3.)
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sfun0  <- stepfun(1:3, y0, f = 0)
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sfun0  <- stepfun(1:3, y0, f = 0)
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sfun.2 <- stepfun(1:3, y0, f = .2)
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sfun.2 <- stepfun(1:3, y0, f = 0.2)
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sfun1  <- stepfun(1:3, y0, f = 1)
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sfun1  <- stepfun(1:3, y0, f = 1)
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sfun1c <- stepfun(1:3, y0, right = TRUE) # hence f=1
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sfun1c <- stepfun(1:3, y0, right = TRUE) # hence f=1
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sfun0
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sfun0
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summary(sfun0)
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summary(sfun0)
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summary(sfun.2)
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summary(sfun.2)
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x0 <- seq(0.5, 3.5, by = 0.25)
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x0 <- seq(0.5, 3.5, by = 0.25)
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rbind(x = x0, f.f0 = sfun0(x0), f.f02 = sfun.2(x0),
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rbind(x = x0, f.f0 = sfun0(x0), f.f02 = sfun.2(x0),
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      f.f1 = sfun1(x0), f.f1c = sfun1c(x0))
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      f.f1 = sfun1(x0), f.f1c = sfun1c(x0))
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## Identities :
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## Identities :
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stopifnot(identical(y0[-1], sfun0 (1:3)),# right = FALSE
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stopifnot(identical(y0[-1], sfun0 (1:3)), # right = FALSE
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          identical(y0[-4], sfun1c(1:3)))# right = TRUE
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          identical(y0[-4], sfun1c(1:3))) # right = TRUE
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}
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}
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\keyword{dplot}
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\keyword{dplot}