JMSL Chart Programmer's Guide
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2D Drawing Elements >> AxisXY >> Axis Label |
Axis Label
The AxisLabel
node controls the labeling of an axis. The drawing of this node
is controlled by the Text Attributes.
Scientific Notation
If the values along an axis are large, scientific notation is more readable than a decimal
format with many zeros. In this example the y-axis is labeled with scientific
notation where each number has exactly two fractional digits displayed. This format
pattern is "0.00E0"
. See java.text.DecimalFormat
for details on
number formatting patterns.
Date Labels
If the TextFormat
attribute for an axis is an instance of DateFormat
, then the
axis is scaled and labeled as a date/time axis, instead of as a real axis.
Date information passed to the Date
constructor must be a double number representing
the number of milliseconds since the standard base time known as "the
epoch", namely January 1, 1970, 00:00:00 GMT. This is used by the constructor
for Date
.
Skipping Weekends
An additional feature of Date
axes is the ability to skip weekends. This feature is
often needed for charting stock price data.
To skip weekends it is necessary to adjust the autoscaling for weekdays-only. This
is done by setting the attribute SkipWeekends
to true. It is also necessary to set
a custom transformation, TransformDate
, on the axis. This is shown in the following
example, which is a modification of the example in the previous section.
Skipping weekends is intended only for data sets where no weekend data exists. It will not give the expected results if the data set contains weekend data.
String Labels
Any array of strings can be used to label the tick marks using the setLabels(String[])
method. The setLabels(String[])
method sets the
Number
attribute to the number of strings.
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