vvget

Extract elements from a vector.

Usage

vvget(x {, o {, d {,n }}})

x

the source vector, l_x=nrow(x) must be greater/equal 1

o

the first element to be extracted, 0 <= o < l_x (default=0)

d

the index increment (default=1)

n

the number of elements to extract, n>0 (default=l_x)

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 l_x-1, otherwise the function failes.

See also

vv, vvset, vvcat, vmcol, vmrow, vsubn, vsubc

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 }

<function list>

vvget

vvget(x, o, d, n)

Result: res[i = 0..n-1] = x[o + i*d]