Impress Guide

Bar charts
Bar charts are excellent for giving an immediate visual impact for data
comparison where time is not important, such as comparing the popularity of a
few products in a marketplace.
Pie charts
Pie charts are excellent when you need to compare proportions, for example,
comparisons of departmental spending: what the department spent on different
items or what different departments spent. They work best with smaller numbers
of values, about half a dozen; more than this and the visual impact begins to fade.
This is one of the charts that can be made into a 3D chart. It can then be tilted,
given shadows, and generally turned into a work of art. You can choose to explode
the pie chart, but this is an all or nothing option, giving you no control over the
degree of separation of the segments.
Area charts
An area chart is a version of a line or column graph. It may be useful where you
wish to emphasize volume of change. Area charts have a greater visual impact
than a line chart, but the data you use will make a difference. You may need to use
transparency values in an area chart.
Line charts
A line chart is a time series with a progression. It is ideal for raw data, and useful
for charts with plentiful data showing trends or changes over time, where you
want to emphasize continuity. On line charts, the x-axis is ideal for representing
time series data. 3D lines confuse the viewer, so just using a thicker line often
works better.
Scatter or XY charts
Scatter charts are great for visualizing data that you have not had time to analyze,
and they may be the best for data when you have a constant value for comparison:
for example weather data, reactions under different acidity levels, conditions at
altitude, or any data which matches two numeric series. The x-axis usually plots
the independent variable or control parameter (often a time series).
Bubble charts
A bubble chart is used to represent three variables: two identify the position of the
center of a bubble on a Cartesian graph, while the third variable indicates the
radius of the bubble.
Net charts
A net chart is similar to polar or radar graphs. They are useful for comparing data
that are not time series, but show different circumstances, such as variables in a
scientific experiment. The poles of the net chart are the y-axes of other charts.
Generally, between three and eight axes are best; any more and this type of chart
becomes confusing.
Stock charts
A stock chart is a specialized column graph specifically for stocks and shares. You
can choose traditional lines, candlestick, and two-column charts. The data
required for these charts is quite specialized, with series for opening price,
closing price, and high and low prices. The x-axis represents a time series.
154 OpenOffice.org 3.3 Impress Guide