Microsoft Office Tutorials and References

In Depth Information

This example is available at this book's website. The filename is scatter chart

timeline.xlsx.

Plotting mathematical functions

The examples in this section demonstrate how to plot mathematical functions that use one variable (a 2-D line

chart) and two variables (a 3-D surface chart). Some of the examples make use of Excel's Data Table feature,

which enables you to evaluate a formula with varying input values.

A Data Table is not the same as a table, created by choosing Insert
⇒
Tables
⇒
Table.

Plotting functions with one variable

An XY chart (also known as a
scatter chart
) is useful for plotting various mathematical and trigonometric func-

tions. For example, Figure 17-14 shows a plot of the SIN function. The chart plots
y
for values of
x
(expressed

in radians) from –5 to +5 in increments of 0.5. Each pair of
x
and
y
values appears as a data point in the chart,

and the points connect with a line.

Excel's trigonometric functions use angles expressed in radians. To convert degrees to

radians, use the RADIANS function.

The function is expressed as

y = SIN(x)

The corresponding formula in cell B2 (which is copied to the cells below) is

=SIN(A2)

Figure 17-15 shows a general-purpose, single-variable plotting application. The data for the chart is calculated

by a data table in columns I:J. Follow these steps to use this application:

1.
Enter a formula in cell B7. The formula should contain at least one
x
variable.

In the figure, the formula in cell B7 is

=SIN(x^3)*COS(x^2)