R: Polynomials

polynomial {polynom} | R Documentation

## Polynomials

### Description

Construct, coerce to, test for, and print polynomial objects.

### Usage

    polynomial(coef = c(0, 1))
    as.polynomial(p)
    is.polynomial(p)

    ## S3 method for class 'polynomial'
    as.character(x, decreasing = FALSE, ...)
    ## S3 method for class 'polynomial'
    print(x, digits = getOption("digits"), decreasing = FALSE, ...)

### Arguments

`coef` | numeric vector, giving the polynomial coefficients in increasing order.
`p` | an arbitrary R object.
`x` | a `polynomial` object.
`decreasing` | a logical specifying the order of the terms; in increasing (default) or decreasing powers.
`digits` | the number of significant digits to use for printing.
`...` | potentially further arguments passed to and from other methods.

### Details

`polynomial` constructs a polynomial from its coefficients, i.e., `p[1:k]` specifies the polynomial

p[1] + p[2]* x + p[3]* x^2 + ... + p[k]* x^(k-1).

Internally, polynomials are simply numeric coefficient vectors of class `"polynomial"`. Several useful methods are available for this class, such as coercion to character (`as.character()`) and function (`as.function.polynomial`), extraction of the coefficients (`coef()`), printing (using `as.character`), plotting (`plot.polynomial`), and computing sums and products of arbitrarily many polynomials.

`as.polynomial` tries to coerce its arguments to a polynomial.

`is.polynomial` tests whether its argument is a polynomial (in the sense that it has class `"polynomial"`.

### Examples

    polynomial(1:4)
    p <- as.polynomial(c(1,0,3,0))
    p
    print(p, decreasing = TRUE)
    stopifnot(coef(p) == c(1,0,3))

    polynomial(c(2,rep(0,10),1))

[Package polynom version 1.3-9 Index]