Tensor of (mixed) partial derivatives

Forms tensor of (mixed) partial derivatives

Usage

Dtensor(expr, name=NULL, mu = NULL, m=1, evaluate = TRUE)

Arguments

expr

'expression'

name

character vector, giving the variable names with respect to which derivatives will be computed. If NULL all variables in the expression will be used

mu

optional: numeric vector, at which the derivatives are evaluated

m

order of derivative

evaluate

logical; if TRUE the derivatives are evaluated at mu, if FALSE the derivatives are left unevaluated

Value

Dtensor

(list) of unevaluated expression(s) if evaluate=FALSE or a tensor if evaluate=TRUE

References

Rice, S.H. (2004) Evolutionary Theory: Mathematical and Conceptual Foundations. Sinauer (MA) USA.

Author

Jarrod Hadfield j.hadfield@ed.ac.uk

See also

evalDtensor, Dexpressions, D

Examples

f<-expression(beta_1 + time * beta_2 + u)
Dtensor(f,eval=FALSE)
#> [[1]]
#> [1] 1
#> 
#> [[2]]
#> beta_2
#> 
#> [[3]]
#> time
#> 
#> [[4]]
#> [1] 1
#>