getCoefficient: Get a coefficient in a 'qspray' polynomial

In qspray: Multivariate Polynomials with Rational Coefficients

Get a coefficient in a 'qspray' polynomial

Description

Get the coefficient of the term with the given monomial.

Usage

## S4 method for signature 'qspray,numeric'
getCoefficient(qspray, exponents)

Arguments

qspray	a qspray object
exponents	a vector of exponents, thereby defining a monomial; trailing zeros are ignored

Value

The coefficient as a bigq number.

Examples

library(qspray)
x <- qlone(1)
y <- qlone(2)
p <- 4*x^2 + 3*y - 5
getCoefficient(p, 2)          # coefficient of x^2
getCoefficient(p, c(2, 0))    # same as getCoefficient(p, 2)
getCoefficient(p, c(0, 1))    # coefficient of y because y=x^0*y^1
getCoefficient(p, 0)          # the constant term
getCoefficient(p, integer(0)) # the constant term 
getCoefficient(p, 3)          # there's no x^3

qspray documentation built on Sept. 11, 2024, 5:33 p.m.