Class LogarithmicAxis

public static final double LOG10_VALUE

Useful constant for log(10).

public static final double SMALL_LOG_VALUE

Smallest arbitrarily-close-to-zero value allowed.

Field Value:

0.0

protected boolean allowNegativesFlag

Flag set true to allow negative values in data.

protected boolean autoRangeNextLogFlag

True to make 'autoAdjustRange()' select "10^n" values.

protected boolean expTickLabelsFlag

Flag set true for "1e#"-style tick labels.

protected boolean log10TickLabelsFlag

Flag set true for "10^n"-style tick labels.

protected final NumberFormat numberFormatterObj

Number formatter for generating numeric strings.

protected boolean smallLogFlag

Helper flag for log axis processing.

protected boolean strictValuesFlag

Flag set true make axis throw exception if any values are <= 0 and 'allowNegativesFlag' is false.

public LogarithmicAxis(String label)

Creates a new axis.

Parameters:

label - the axis label.

public double adjustedLog10(double val)

Returns an adjusted log10 value for graphing purposes. The first adjustment is that negative values are changed to positive during the calculations, and then the answer is negated at the end. The second is that, for values less than 10, an increasingly large (0 to 1) scaling factor is added such that at 0 the value is adjusted to 1, resulting in a returned result of 0.

Parameters:

val - value for which log10 should be calculated.

Returns:

An adjusted log₁₀(val).

See Also:

adjustedPow10(double)

public double adjustedPow10(double val)

Returns an adjusted power of 10 value for graphing purposes. The first adjustment is that negative values are changed to positive during the calculations, and then the answer is negated at the end. The second is that, for values less than 1, a progressive logarithmic offset is subtracted such that at 0 the returned result is also 0.

Parameters:

val - value for which power of 10 should be calculated.

Returns:

An adjusted 10^val.

Since:

1.0.5

See Also:

adjustedLog10(double)

public void autoAdjustRange()

Rescales the axis to ensure that all data is visible.

Overrides:

autoAdjustRange in interface NumberAxis

protected double computeLogCeil(double upper)

Returns the smallest (closest to negative infinity) double value that is not less than the argument, is equal to a mathematical integer and satisfying the condition that log base 10 of the value is an integer (i.e., the value returned will be a power of 10: 1, 10, 100, 1000, etc.).

Parameters:

upper - a double value above which a ceiling will be calcualted.

Returns:

10^N with N .. { 1 ... }

protected double computeLogFloor(double lower)

Returns the largest (closest to positive infinity) double value that is not greater than the argument, is equal to a mathematical integer and satisfying the condition that log base 10 of the value is an integer (i.e., the value returned will be a power of 10: 1, 10, 100, 1000, etc.).

Parameters:

lower - a double value below which a floor will be calcualted.

Returns:

10^N with N .. { 1 ... }

public boolean getAllowNegativesFlag()

Returns the 'allowNegativesFlag' flag; true to allow negative values in data, false to be able to plot positive values arbitrarily close to zero.

Returns:

The flag.

public boolean getAutoRangeNextLogFlag()

Returns the 'autoRangeNextLogFlag' flag.

Returns:

true if the 'autoAdjustRange()' method will select the next "10^n" values, false if not.

public boolean getExpTickLabelsFlag()

Returns the 'expTickLabelsFlag' flag.

Returns:

true for "1e#"-style tick labels, false for log10 or regular numeric tick labels.

public boolean getLog10TickLabelsFlag()

Returns the 'log10TickLabelsFlag' flag.

Returns:

true for "10^n"-style tick labels, false for "1e#"-style or regular numeric tick labels.

public boolean getStrictValuesFlag()

Returns the 'strictValuesFlag' flag; if true and 'allowNegativesFlag' is false then this axis will throw a runtime exception if any of its values are less than or equal to zero; if false then the axis will adjust for values less than or equal to zero as needed.

Returns:

true if strict enforcement is enabled.

public double java2DToValue(double java2DValue,
                            Rectangle2D plotArea,
                            RectangleEdge edge)

Converts a coordinate in Java2D space to the corresponding data value, assuming that the axis runs along one edge of the specified plotArea.

Overrides:

java2DToValue in interface NumberAxis

Parameters:

java2DValue - the coordinate in Java2D space.

plotArea - the area in which the data is plotted.

edge - the axis location.

Returns:

The data value.

protected String makeTickLabel(double val)

Converts the given value to a tick label string.

Parameters:

val - the value to convert.

Returns:

The tick label string.

protected String makeTickLabel(double val,
                               boolean forceFmtFlag)

Converts the given value to a tick label string.

Parameters:

val - the value to convert.

forceFmtFlag - true to force the number-formatter object to be used.

Returns:

The tick label string.

protected List refreshTicksHorizontal(Graphics2D g2,
                                      Rectangle2D dataArea,
                                      RectangleEdge edge)

Calculates the positions of the tick labels for the axis, storing the results in the tick label list (ready for drawing).

Overrides:

refreshTicksHorizontal in interface NumberAxis

Parameters:

g2 - the graphics device.

dataArea - the area in which the plot should be drawn.

edge - the location of the axis.

Returns:

A list of ticks.

protected List refreshTicksVertical(Graphics2D g2,
                                    Rectangle2D dataArea,
                                    RectangleEdge edge)

Calculates the positions of the tick labels for the axis, storing the results in the tick label list (ready for drawing).

Overrides:

refreshTicksVertical in interface NumberAxis

Parameters:

g2 - the graphics device.

dataArea - the area in which the plot should be drawn.

edge - the location of the axis.

Returns:

A list of ticks.

public void setAllowNegativesFlag(boolean flgVal)

Sets the 'allowNegativesFlag' flag; true to allow negative values in data, false to be able to plot positive values arbitrarily close to zero.

Parameters:

flgVal - the new value of the flag.

public void setAutoRangeNextLogFlag(boolean flag)

Sets the 'autoRangeNextLogFlag' flag. This determines whether or not the 'autoAdjustRange()' method will select the next "10^n" values when determining the upper and lower bounds. The default value is false.

Parameters:

flag - true to make the 'autoAdjustRange()' method select the next "10^n" values, false to not.

public void setExpTickLabelsFlag(boolean flgVal)

Sets the 'expTickLabelsFlag' flag. If the 'log10TickLabelsFlag' is false then this will set whether or not "1e#"-style tick labels are used. The default is to use regular numeric tick labels.

Parameters:

flgVal - true for "1e#"-style tick labels, false for log10 or regular numeric tick labels.

public void setLog10TickLabelsFlag(boolean flag)

Sets the 'log10TickLabelsFlag' flag. The default value is false.

Parameters:

flag - true for "10^n"-style tick labels, false for "1e#"-style or regular numeric tick labels.

public void setRange(Range range)

Overridden version that calls original and then sets up flag for log axis processing.

Overrides:

setRange in interface ValueAxis

Parameters:

range - the new range.

public void setStrictValuesFlag(boolean flgVal)

Sets the 'strictValuesFlag' flag; if true and 'allowNegativesFlag' is false then this axis will throw a runtime exception if any of its values are less than or equal to zero; if false then the axis will adjust for values less than or equal to zero as needed.

Parameters:

flgVal - true for strict enforcement.

protected void setupNumberFmtObj()

Sets up the number formatter object according to the 'expTickLabelsFlag' flag.

protected void setupSmallLogFlag()

Sets up flag for log axis processing. Set true if negative values not allowed and the lower bound is between 0 and 10.

protected double switchedLog10(double val)

Returns the log10 value, depending on if values between 0 and 1 are being plotted. If negative values are not allowed and the lower bound is between 0 and 10 then a normal log is returned; otherwise the returned value is adjusted if the given value is less than 10.

Parameters:

val - the value.

Returns:

log₁₀(val).

See Also:

switchedPow10(double)

public double switchedPow10(double val)

Returns a power of 10, depending on if values between 0 and 1 are being plotted. If negative values are not allowed and the lower bound is between 0 and 10 then a normal power is returned; otherwise the returned value is adjusted if the given value is less than 1.

Parameters:

val - the value.

Returns:

10^val.

Since:

1.0.5

See Also:

switchedLog10(double)

public double valueToJava2D(double value,
                            Rectangle2D plotArea,
                            RectangleEdge edge)

Converts a data value to a coordinate in Java2D space, assuming that the axis runs along one edge of the specified plotArea. Note that it is possible for the coordinate to fall outside the plotArea.

Overrides:

valueToJava2D in interface NumberAxis

Parameters:

value - the data value.

plotArea - the area for plotting the data.

edge - the axis location.

Returns:

The Java2D coordinate.

public void zoomRange(double lowerPercent,
                      double upperPercent)

Zooms in on the current range.

Overrides:

zoomRange in interface ValueAxis

Parameters:

lowerPercent - the new lower bound.

upperPercent - the new upper bound.