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Charts IV: Charts for the scientist

Chart with two axes, arithmetic and logarithmic. The data is shown against both scales

The same set of data shown on a logarithmic scale and a linear scale.

With exponential data, if you plot the data on a chart with normal axes, you'll see the typical exponential curve. However, if you use a logarithmic axis, then you'll see a straight line. But how do you change from one to the other?

It's a very simple process: You just need to select a check box in the Format Axis dialog box. You'll see exactly how to do this in the practice session.

Logarithmic scales are also useful if your data contains some very small numbers with a gap in the data, followed by a very large number. On a linear scale you would have a large gap in the middle of the chart; with a log scale, this is evened out.

Note    The values on a logarithmic axis are only ever shown in powers of 10.

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