class QLogValueAxis#

The QLogValueAxis class adds a logarithmic scale to a chart’s axis. More…

Synopsis#

Properties#

baseᅟ - Of the logarithm
labelFormatᅟ - Label format of the axis
maxᅟ - Maximum value on the axis
minᅟ - Minimum value on the axis
minorTickCountᅟ - Number of minor tick marks on the axis. This indicates how many grid lines are drawn between major ticks on the chart. Labels are not drawn for minor ticks. The default value is 0. Set the value to -1 and the number of grid lines between major ticks will be calculated automatically
tickCountᅟ - Number of tick marks on the axis. This indicates how many grid lines are drawn on the chart. This value is read-only

Methods#

def __init__()
def base()
def labelFormat()
def max()
def min()
def minorTickCount()
def setBase()
def setLabelFormat()
def setMax()
def setMin()
def setMinorTickCount()
def setRange()
def tickCount()

Note

This documentation may contain snippets that were automatically translated from C++ to Python. We always welcome contributions to the snippet translation. If you see an issue with the translation, you can also let us know by creating a ticket on https:/bugreports.qt.io/projects/PYSIDE

Detailed Description#

A logarithmic scale is a nonlinear scale that is based on orders of magnitude, so that each tick mark on the axis is the previous tick mark multiplied by a value.

Note

If QLogValueAxis is attached to a series with one or more points with negative or zero values on the associated dimension, the series will not be plotted at all. This is particularly relevant when XYModelMappers are used, since empty cells in models typically contain zero values.

Note

Properties can be used directly when from __feature__ import true_property is used or via accessor functions otherwise.

property baseᅟ: float#

This property holds The base of the logarithm..

The value has to be greater than 0 and cannot equal 1.

Access functions:

base()
setBase()
Signal baseChanged()

property labelFormatᅟ: str#

This property holds The label format of the axis..

The format string supports the following conversion specifiers, length modifiers, and flags provided by printf() in the standard C++ library: d, i, o, x, X, f, F, e, E, g, G, c.

If localizeNumbers is true, the supported specifiers are limited to: d, e, E, f, g, G, and i. Also, only the precision modifier is supported. The rest of the formatting comes from the default QLocale of the application.

See also

asprintf()

Access functions:

labelFormat()
setLabelFormat()
Signal labelFormatChanged()

property maxᅟ: float#

This property holds The maximum value on the axis..

When setting this property, the minimum value is adjusted if necessary, to ensure that the range remains valid. The value has to be greater than 0.

Access functions:

max()
setMax()
Signal maxChanged()

property minᅟ: float#

This property holds The minimum value on the axis..

When setting this property, the maximum value is adjusted if necessary, to ensure that the range remains valid. The value has to be greater than 0.

Access functions:

min()
setMin()
Signal minChanged()

property minorTickCountᅟ: int#

This property holds The number of minor tick marks on the axis. This indicates how many grid lines are drawn between major ticks on the chart. Labels are not drawn for minor ticks. The default value is 0. Set the value to -1 and the number of grid lines between major ticks will be calculated automatically..

Access functions:

minorTickCount()
setMinorTickCount()
Signal minorTickCountChanged()

property tickCountᅟ: int#

This property holds The number of tick marks on the axis. This indicates how many grid lines are drawn on the chart. This value is read-only..

Access functions:

tickCount()
Signal tickCountChanged()

__init__([parent=None])#

Parameters:: parent – QObject

Constructs an axis object that is a child of parent.

base()#

Return type:: float

See also

setBase()

Getter of property baseᅟ .

baseChanged(base)#

Parameters:: base – float

This signal is emitted when the base of the logarithm of the axis changes.

Notification signal of property baseᅟ .

labelFormat()#

Return type:: str

See also

setLabelFormat()

Getter of property labelFormatᅟ .

labelFormatChanged(format)#

Parameters:: format – str

This signal is emitted when the format of axis labels changes.

Notification signal of property labelFormatᅟ .

max()#

Return type:: float

See also

setMax()

Getter of property maxᅟ .

maxChanged(max)#

Parameters:: max – float

This signal is emitted when the maximum value of the axis, specified by max, changes.

Notification signal of property maxᅟ .

min()#

Return type:: float

See also

setMin()

Getter of property minᅟ .

minChanged(min)#

Parameters:: min – float

This signal is emitted when the minimum value of the axis, specified by min, changes.

Notification signal of property minᅟ .

minorTickCount()#

Return type:: int

See also

setMinorTickCount()

Getter of property minorTickCountᅟ .

minorTickCountChanged(minorTickCount)#

Parameters:: minorTickCount – int

This signal is emitted when the number of minor tick marks on the axis, specified by minorTickCount, changes.

Notification signal of property minorTickCountᅟ .

rangeChanged(min, max)#

Parameters:

min – float
max – float

This signal is emitted when the minimum or maximum value of the axis, specified by min and max, changes.

setBase(base)#

Parameters:: base – float

See also

base()

Setter of property baseᅟ .

setLabelFormat(format)#

Parameters:: format – str

See also

labelFormat()

Setter of property labelFormatᅟ .

setMax(max)#

Parameters:: max – float

See also

max()

Setter of property maxᅟ .

setMin(min)#

Parameters:: min – float

See also

min()

Setter of property minᅟ .

setMinorTickCount(minorTickCount)#

Parameters:: minorTickCount – int

See also

minorTickCount()

Setter of property minorTickCountᅟ .

setRange(min, max)#

Parameters:

min – float
max – float

Sets the range from min to max on the axis. If min is greater than max, this function returns without making any changes.

tickCount()#

Return type:: int

Getter of property tickCountᅟ .

tickCountChanged(tickCount)#

Parameters:: tickCount – int

This signal is emitted when the number of tick marks on the axis, specified by tickCount, changes.

Notification signal of property tickCountᅟ .