LogValueAxis QML Type

Adds a logarithmic scale to a chart's axis. 更多...

import 语句: import QtCharts 2.3
实例化: QLogValueAxis
继承: AbstractAxis

特性

信号

详细描述

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.

注意: LogValueAxis type 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.

特性文档编制

base : real

The base of the logarithm.

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

labelFormat : real

The label format of the axis.

格式字符串支持的以下转换说明符、长度修饰符和标志的提供通过 printf() 在标准 C++ 库:d、i、o、x、X、f、F、e、E、g、G、c。

ChartView.localizeNumbers is true ,支持的说明符限于:d、e、E、f、g、G 和 i。另外,仅支持精度修饰符。其余格式来自默认 QLocale 对于应用程序。

另请参阅 QString::asprintf() .

max : real

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.

min : real

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.

minorTickCount : int

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.

tickCount : int

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


信号文档编制

minorTickCountChanged ( int minorTickCount )

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

tickCountChanged ( int tickCount )

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