### symbolic Laplacian
laplacian("x^3+y^3+z^3", var = c("x","y","z"))
### numerical Laplacian in (x=1, y=1, z=1)
f <- function(x, y, z) x^3+y^3+z^3
laplacian(f = f, var = c(x=1, y=1, z=1))
### vectorized interface
f <- function(x) sum(x^3)
laplacian(f = f, var = c(1, 1, 1))
### symbolic vector-valued functions
f <- array(c("x^2","x*y","x*y","y^2"), dim = c(2,2))
laplacian(f = f, var = c("x","y"))
### numerical vector-valued functions
f <- function(x, y) array(c(x^2,x*y,x*y,y^2), dim = c(2,2))
laplacian(f = f, var = c(x=0,y=0))
### binary operator
"x^3+y^3+z^3" %laplacian% c("x","y","z")
Run the code above in your browser using DataLab