MATLAB Examples

# Using Treemaps

Treemaps display data using the relative areas of nested rectangles. See http://en.wikipedia.org/wiki/Treemapping for more information.

## By itself

You can call treemap by itself and it will run with fake data.

```cla treemap; ```

## With data

Here's how you pass in your own data.

```cla data = rand(1,20); treemap(data); ```

## Custom colors and labels

You can capture the rectangles and use plotRectangles to display them with your own colors and labels.

```n = 15; data = rand(1,n); colors = (jet(n)+1)/2; % Add labels labels = {}; for i = 1:n labels{i} = sprintf('%2.1f%%',100*data(i)/sum(data)); end cla rectangles = treemap(data); plotRectangles(rectangles,labels,colors) ```

## Another example

```data = ... {'Alaska',571951; 'Texas' 261797; 'California',155959; 'Montana',145552; 'New Mexico',121356; 'Arizona',113635; 'Nevada',109826; 'Colorado',103718; 'Oregon',95997}; colors = ones(10,3); rectangles = treemap([data{:,2}]); labels = data(:,1); cla plotRectangles(rectangles,labels,colors) outline(rectangles) axis([-0.01 1.01 -0.01 1.01]) title('The Ten Biggest U.S. States') ```

## Nested treemaps

You can plot treemaps within treemaps

```m = 12; n = 20; data = rand(m,n); % Lay out the column totals level1 = sum(data); cla reset r = treemap(level1); % Lay out each column within that column's rectangle from the overall % layout for j = 1:n colors = (3*repmat(rand(1,3),m,1) + rand(m,3))/4; rNew = treemap(data(:,j),r(3,j),r(4,j)); rNew(1,:) = rNew(1,:) + r(1,j); rNew(2,:) = rNew(2,:) + r(2,j); plotRectangles(rNew,[],colors) end outline(r) axis([-0.01 1.01 -0.01 1.01]) ```