FreeMat

- Main Page
- Related Pages

SPONES Sparse Ones Function

Section: Sparse Matrix Support

# Usage

Returns a sparse `float` matrix with ones where the argument matrix has nonzero values. The general syntax for it is

      y = spones(x)

where `x` is a matrix (it may be full or sparse). The output matrix `y` is the same size as `x`, has type `float`, and contains ones in the nonzero positions of `x`.

# Examples

Here are some examples of the `spones` function

    --> a = [1,0,3,0,5;0,0,2,3,0;1,0,0,0,1]

    a =
     1 0 3 0 5
     0 0 2 3 0
     1 0 0 0 1

    --> b = spones(a)

    b =
     1 1 1
     1 2 1
     1 3 1
     1 4 1
     1 5 1
    --> full(b)

    ans =
     1 1 1 1 1
     0 0 0 0 0
     0 0 0 0 0