Class: ezcGraphChartElementNumericAxis  - X-Ref

Class to represent a numeric axis.

Axis elements represent the axis in a bar, line or radar chart. They are
chart elements (ezcGraphChartElement) extending from
ezcGraphChartElementAxis, where additional formatting options can be found.
You should generally use the axis, which matches your input data best, so
that the automatic chart layouting works best. Aavailable axis types are:

- ezcGraphChartElementDateAxis
- ezcGraphChartElementLabeledAxis
- ezcGraphChartElementLogarithmicalAxis
- ezcGraphChartElementNumericAxis

The axis tries to calculate "nice" start and end values for the axis scale.
The used interval is considered as nice, if it is equal to [1,2,5] * 10^x
with x in [.., -1, 0, 1, ..].

The start and end value are the next bigger / smaller multiple of the
intervall compared to the maximum / minimum axis value.

You may specify custom step sizes using the properties $majorStep and
$minorStep. The minimum and maximum values for the axis labels can be
defined using the $min and $max properties. You should be able to set any
subset of these values, and all values not explicitely set will be
calculated automatically.

This axis should be used for all numeric values except dates. If your data
does span very big number intervals you might want to consider using the
logrithmic axis instead.

The numeric axis may be used like:

<code>
$graph = new ezcGraphLineChart();
$graph->title = 'Some random data';
$graph->legend = false;

$graph->xAxis = new ezcGraphChartElementNumericAxis();
// The y axis is numeric by default.

$graph->xAxis->min = -15;
$graph->xAxis->max = 15;
$graph->xAxis->majorStep = 5;

$data = array(
array(),
array()
);
for ( $i = -10; $i <= 10; $i++ )
{
$data[0][$i] = mt_rand( -23, 59 );
$data[1][$i] = mt_rand( -23, 59 );
}

// Add data
$graph->data['random blue'] = new ezcGraphArrayDataSet( $data[0] );
$graph->data['random green'] = new ezcGraphArrayDataSet( $data[1] );

$graph->render( 400, 150, 'tutorial_axis_numeric.svg' );
</code>