R: Graphical display of polynomial objects

plot.polynom {PolynomF} | R Documentation

## Graphical display of polynomial objects

### Description

Standard displsy methods for polynomial or lists of polynomials.

### Usage

    ## S3 method for class 'polynom'
    plot(x, xlim = 0:1, ylim = range(Px), type = "l",
       xlab = "x", ylab = "p(x)", ..., len = 1000)
    ## S3 method for class 'polylist'
    plot(x, xlim = 0:1, ylim = range(Px), type = "l",
       xlab = "x", ylab = "P(x)", ..., len = 1000)
    ## S3 method for class 'polylist'
    lines(x, ..., len = 1000)
    ## S3 method for class 'polynom'
    lines(x, ..., len = 1000)
    ## S3 method for class 'polylist'
    points(x, ..., len = 100)
    ## S3 method for class 'polynom'
    points(x, ..., at = seq(pu[1], pu[2], len = len), len = 100)

### Arguments

`x` | A `polynom` or `polylist` object.
`xlim, ylim, xlab, ylab, type` | As for `plot`.
`...` | Additional arguments sent to `plot`, `points` or `lines`
`len` | The number of linear line segments to use to present the polynomial curve.
`at` | the $x-$values where the points are to appear.

### Details

`plot.polynom` will by default choose `x` limits to cover the (real parts of) the zeros, stationary points and points of inflexion of the ploynomial being plotted. `plot.polylist` chooses by default an x region to accommodate all polynomials on the list in this way. The current palette of colours is used for different components. `lines.polynom` may be used to add individual polynomials to the plot. The argument `len` may be used to increase or decrease the number of straight line segments used to represent the curves.

### Value

Nothing of use.

### Author(s)

Bill Venables, with contributions by Kurt Hornik.

### References

Nont

### See Also

`curve`

### Examples

    x <- polynom()
    L <- polylist(1, 1-x)
    for(j in 2:10) L[[j+1]] <- (2*j - 1 - x)*L[[j]] - (j-1)^2*L[[j-1]]
    plot(L[1:5], xlim = c(0,5), xaxs = "r", ylab = expression(L[j](z)),
    xlab = "z", main = "Laguerre polynomials to degree 4")

    lines(L[[6]], col = "grey", lwd = 2)

[Package PolynomF version 1.0-1 Index]