org.jfree.chart.axis

Class LogarithmicAxis

public class LogarithmicAxis extends NumberAxis

A numerical axis that uses a logarithmic scale.
Field Summary
protected booleanallowNegativesFlag
Flag set true to allow negative values in data.
protected booleanautoRangeNextLogFlag
True to make 'autoAdjustRange()' select "10^n" values.
protected booleanexpTickLabelsFlag
Flag set true for "1e#"-style tick labels.
protected booleanlog10TickLabelsFlag
Flag set true for "10^n"-style tick labels.
static doubleLOG10_VALUE
Useful constant for log(10).
protected NumberFormatnumberFormatterObj
Number formatter for generating numeric strings.
protected booleansmallLogFlag
Helper flag for log axis processing.
protected booleanstrictValuesFlag
Flag set true make axis throw exception if any values are <= 0 and 'allowNegativesFlag' is false.
static doubleSMALL_LOG_VALUE
Smallest arbitrarily-close-to-zero value allowed.
Constructor Summary
LogarithmicAxis(String label)
Creates a new axis.
Method Summary
doubleadjustedLog10(double val)
Returns an adjusted log10 value for graphing purposes.
doubleadjustedPow10(double val)
Returns an adjusted power of 10 value for graphing purposes.
voidautoAdjustRange()
Rescales the axis to ensure that all data is visible.
protected doublecomputeLogCeil(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.).
protected doublecomputeLogFloor(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.).
booleangetAllowNegativesFlag()
Returns the 'allowNegativesFlag' flag; true to allow negative values in data, false to be able to plot positive values arbitrarily close to zero.
booleangetAutoRangeNextLogFlag()
Returns the 'autoRangeNextLogFlag' flag.
booleangetExpTickLabelsFlag()
Returns the 'expTickLabelsFlag' flag.
booleangetLog10TickLabelsFlag()
Returns the 'log10TickLabelsFlag' flag.
booleangetStrictValuesFlag()
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.
doublejava2DToValue(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.
protected StringmakeTickLabel(double val, boolean forceFmtFlag)
Converts the given value to a tick label string.
protected StringmakeTickLabel(double val)
Converts the given value to a tick label string.
protected ListrefreshTicksHorizontal(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).
protected ListrefreshTicksVertical(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).
voidsetAllowNegativesFlag(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.
voidsetAutoRangeNextLogFlag(boolean flag)
Sets the 'autoRangeNextLogFlag' flag.
voidsetExpTickLabelsFlag(boolean flgVal)
Sets the 'expTickLabelsFlag' flag.
voidsetLog10TickLabelsFlag(boolean flag)
Sets the 'log10TickLabelsFlag' flag.
voidsetRange(Range range)
Overridden version that calls original and then sets up flag for log axis processing.
voidsetStrictValuesFlag(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.
protected voidsetupNumberFmtObj()
Sets up the number formatter object according to the 'expTickLabelsFlag' flag.
protected voidsetupSmallLogFlag()
Sets up flag for log axis processing.
protected doubleswitchedLog10(double val)
Returns the log10 value, depending on if values between 0 and 1 are being plotted.
doubleswitchedPow10(double val)
Returns a power of 10, depending on if values between 0 and 1 are being plotted.
doublevalueToJava2D(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.
voidzoomRange(double lowerPercent, double upperPercent)
Zooms in on the current range.

Field Detail

allowNegativesFlag

protected boolean allowNegativesFlag
Flag set true to allow negative values in data.

autoRangeNextLogFlag

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

expTickLabelsFlag

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

log10TickLabelsFlag

protected boolean log10TickLabelsFlag
Flag set true for "10^n"-style tick labels.

LOG10_VALUE

public static final double LOG10_VALUE
Useful constant for log(10).

numberFormatterObj

protected final NumberFormat numberFormatterObj
Number formatter for generating numeric strings.

smallLogFlag

protected boolean smallLogFlag
Helper flag for log axis processing.

strictValuesFlag

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

SMALL_LOG_VALUE

public static final double SMALL_LOG_VALUE
Smallest arbitrarily-close-to-zero value allowed.

Constructor Detail

LogarithmicAxis

public LogarithmicAxis(String label)
Creates a new axis.

Parameters: label the axis label.

Method Detail

adjustedLog10

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: LogarithmicAxis

adjustedPow10

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 10val.

Since: 1.0.5

See Also: LogarithmicAxis

autoAdjustRange

public void autoAdjustRange()
Rescales the axis to ensure that all data is visible.

computeLogCeil

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: 10N with N .. { 1 ... }

computeLogFloor

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: 10N with N .. { 1 ... }

getAllowNegativesFlag

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.

getAutoRangeNextLogFlag

public boolean getAutoRangeNextLogFlag()
Returns the 'autoRangeNextLogFlag' flag.

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

getExpTickLabelsFlag

public boolean getExpTickLabelsFlag()
Returns the 'expTickLabelsFlag' flag.

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

getLog10TickLabelsFlag

public boolean getLog10TickLabelsFlag()
Returns the 'log10TickLabelsFlag' flag.

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

getStrictValuesFlag

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.

java2DToValue

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.

Parameters: java2DValue the coordinate in Java2D space. plotArea the area in which the data is plotted. edge the axis location.

Returns: The data value.

makeTickLabel

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.

makeTickLabel

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.

refreshTicksHorizontal

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).

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.

refreshTicksVertical

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).

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.

setAllowNegativesFlag

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.

setAutoRangeNextLogFlag

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.

setExpTickLabelsFlag

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.

setLog10TickLabelsFlag

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.

setRange

public void setRange(Range range)
Overridden version that calls original and then sets up flag for log axis processing.

Parameters: range the new range.

setStrictValuesFlag

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.

setupNumberFmtObj

protected void setupNumberFmtObj()
Sets up the number formatter object according to the 'expTickLabelsFlag' flag.

setupSmallLogFlag

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.

switchedLog10

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: LogarithmicAxis

switchedPow10

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: 10val.

Since: 1.0.5

See Also: LogarithmicAxis

valueToJava2D

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.

Parameters: value the data value. plotArea the area for plotting the data. edge the axis location.

Returns: The Java2D coordinate.

zoomRange

public void zoomRange(double lowerPercent, double upperPercent)
Zooms in on the current range.

Parameters: lowerPercent the new lower bound. upperPercent the new upper bound.