Does SMath have equivalent commands to Mathcad's "length(v)" and "last(v)" for returning the number of elements in vector "v"?

More specifically, I'm looking to translate the following Mathcad statements into SMath.

i:=0..last ⎛ ⎝Ln⟨0⟩⎞⎠ where Ln contains a previously-assigned 3x3 matrix of values
j≔0‥2

Wrote

Does SMath have equivalent commands to Mathcad's "length(v)" and "last(v)" for returning the number of elements in vector "v"?

1. length),) ... from f(x) menu
2. code last(,) like this => last(v):=rows(v)
last(,) in Mathcad is redondant !