Get body of function as an expression.
bodyAsExpression(x)
An R function.
An expression.
This function is similar to the R body
function except that function
returns a call object whereas this one returns an expression usable in
Ryacas calculations.
# construct an R function for the Burr probability density
# function (PDF) given the Burr cumulative distribution function (CDF)
BurrCDF <- function(x, c = 1, k = 1) 1-(1+x^c)^-k
# transfer CDF to yacas
yacas(BurrCDF)
#> yacas_expression(TRUE)
# create a template for the PDF from the CDF
BurrPDF <- BurrCDF
# differentiate CDF and place resulting expression in body
body(BurrPDF) <- yacas(expression(deriv(BurrCDF(x,c,k))))[[1]]
# test out PDF
BurrPDF(1)
#> [1] 0.25