# countwts¶

## Purpose¶

Returns a weighted count of the numbers of elements of a vector that fall into specified ranges.

## Format¶

c = countwts(x, v, w)
Parameters:
• x (Nx1 vector) – the numbers to be counted.

• v (Px1 vector) – the breakpoints specifying the ranges within which counts are to be made. This MUST be sorted in ascending order (lowest to highest).

• w (Nx1 vector) – weights.

Returns:

c (Px1 vector) –

the weighted counts of the elements of x that fall into the regions:

$\begin{split}x < v,\\ v ≤ x < v,\\ \vdots\\ v[p-1] ≤ x < v[p]\end{split}$

That is, when $$x[i]$$ falls into region j, the weight $$w[i]$$ is added to the jth counter.

## Examples¶

// Original data
x = { 1, 3, 2, 4, 1, 3 };

// Weights
w = { .25, 1, .333, .1, .25, 1 };

// Break points
v = { 0, 1, 2, 3, 4 };

// Get counts
c = countwts(x,v,w);

    0.0000000
0.5000000
c = 0.3330000
2.0000000
0.1000000


## Remarks¶

If any elements of x are greater than the last element of v, they will not be counted.

Missing values are not counted unless there is a missing in v. A missing value in v MUST be the first element in v.