vvget

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Extract elements from a vector.

Usage
vvget(x {, o {, d {,n }}})
x
the source vector, lx=nrow(x) must be greater/equal 1
o
the first element to be extracted, 0 ≤ o < lx (default=0)
d
the index increment (default=1)
n
the number of elements to extract, n>0 (default=lx)
Result
A numerical object r (scalar or vector) with n elements
ri = xo+i*d; with i=0..n-1
Note: For all i, the source index o+i*d must be in the range 0 to lx-1, otherwise the function fails.
See also
vv, vvset, vvcat, vmcol, vmrow, vsubn, vsubc

<function list>


Example:

#a := eval vv(1,2,4,8,16,32)
#b := eval vvget($#a, 0, 2, 3) 
// → #b = { 1 , 4 , 16 }
#c := eval vvget($#a, 5, -1, 4)
// → #c = { 32, 16, 8, 4 }