Python 向reportlab线型图添加日期标签

我正在使用reportlab生成线形图。我似乎无法获得X轴的非数字标签。

有人有什么想法吗

这是我的线形图课程（注意：我在这个课程之外做了一些计算和设置，但是你可以得到要点

import reportlab
from advisor.charting.Font import Font

from reportlab.lib.colors import Color, HexColor
from reportlab.lib.pagesizes import cm, inch
from reportlab.graphics.charts.legends import Legend
from reportlab.graphics.charts.textlabels import Label
from reportlab.graphics.charts.linecharts import HorizontalLineChart
from reportlab.graphics.charts.lineplots import LinePlot
from reportlab.graphics.shapes import Drawing, String, _DrawingEditorMixin
from reportlab.graphics.widgets.markers import makeMarker


class TacticalAugLineGraph(_DrawingEditorMixin, Drawing):       
    def __init__(self, width=100, height=110, legend=False, *args, **kw):
        apply(Drawing.__init__, (self, width, height) + args, kw)

        chartFont = Font('Gotham-Bold')

        self._add(self, LinePlot(), name='chart', validate=None, desc=None)
        self.chart._inFill = 1
        self.chart.x                = 20
        self.chart.y                = 15
        self.chart.width        = 85
        self.chart.height   = 95

        #self.chart.lineLabelFormat = '%d%%'
        self.chart.yValueAxis.valueMin = 0
        self.chart.yValueAxis.valueMax = 100
        self.chart.yValueAxis.valueStep = 10

    def apply_colors(self, colors):

        self.chart.lines[0].strokeColor = colors[0]
        self.chart.lines[1].strokeColor = colors[1]
        self.chart.lines[2].strokeColor = colors[2]
        self.chart.lines[3].strokeColor = colors[3]

---

我制作了一个简单的示例，您可以对其进行测试。结果如下：

在格式化程序中有两个可选的返回语句，您可以使用它们来更好地掌握它

当然，如果x轴上的数据是从日期开始的，则不需要任何格式设置程序，在这种情况下，您可以只指定标签的位置（如果您对默认位置不满意）

上面的例子借用了本书第105页的观点

祝你好运：）

#!/usr/bin/python
from reportlab.graphics.charts.lineplots import LinePlot
from reportlab.graphics.shapes import Drawing
from reportlab.lib import colors
from random import randint
from datetime import date, timedelta

# Generate some testdata
data = [
    [(x,randint(90,100)) for x in range(0,2001,100)],
    [(x,randint(30,80)) for x in range(0,2001,100)],
    [(x,randint(5,20)) for x in range(0,2001,100)],
    ]

# Create the drawing and the lineplot
drawing = Drawing(400, 200)
lp = LinePlot()
lp.x = 50
lp.y = 50
lp.height = 125
lp.width = 300
lp._inFill = 1
lp.data = data
for i in range(len(data)):
    lp.lines[i].strokeColor = colors.toColor('hsl(%s,80%%,40%%)'%(i*60))

# Specify where the labels should be
lp.xValueAxis.valueSteps = [5, 500, 1402, 1988]
# Create a formatter that takes the value and format it however you like.
def formatter(val):
    #return val
    #return 'x=%s'%val
    return (date(2010,1,1) + timedelta(val)).strftime('%Y-%m-%d')

# Use the formatter
lp.xValueAxis.labelTextFormat = formatter
drawing.add(lp)

from reportlab.graphics import renderPDF
renderPDF.drawToFile(drawing, 'example.pdf', 'lineplot with dates')