2019-08-06|2019-08-06 python-pygal画图 2019-08-06python-pygal画图

pygal是个非常简单且功能丰富的py画图包，折线图、柱状图、饼图等常见和不常见的图像都可轻松实现。
解决中文字体问题、Linux系统乱码问题，输出PNG文件问题 【2019-08-06|2019-08-06 python-pygal画图】安装：
pip install pygal
文档特别详细：
http://www.pygal.org/en/stable/documentation/index.html
如下为官网折线图实例：

line_chart = pygal.Line() line_chart.title = 'Browser usage evolution (in %)' line_chart.x_labels = map(str, range(2002, 2013)) line_chart.add('Firefox', [None, None,0, 16.6,25,31, 36.4, 45.5, 46.3, 42.8, 37.1]) line_chart.add('Chrome',[None, None, None, None, None, None,0,3.9, 10.8, 23.8, 35.3]) line_chart.add('IE',[85.8, 84.6, 84.7, 74.5,66, 58.6, 54.7, 44.8, 36.2, 26.6, 20.1]) line_chart.add('Others',[14.2, 15.4, 15.3,8.9,9, 10.4,8.9,5.8,6.7,6.8,7.5]) chart.render()# Return the svg as bytes

文章图片
image.png

设置x轴数据：line_chart.x_labels
y轴数据：line_chart.add
绘图：line_chart.render()
保存输出：
bytes：chart.render() # Return the svg as bytes
svg文件：chart.render_to_file('/tmp/chart.svg')
png图片：chart.render_to_png('/tmp/chart.png')

pygal对输出图片,及中文不够友好，需要引入其他依赖包。
pip install webencodings
pip install tinycss2
pip install defusedxml
pip install cssselect2
pip install cairocffi
pip install CairoSVG
如果是linux环境安装cairo容易失败，可以下载对应的系统包进行安装：
https://launchpad.net/ubuntu/+source/pycairo/
我的ubuntu环境下载的：
python3-cairo_1.16.2-1_amd64.deb
安装：dpkg -i python3-cairo_1.16.2-1_amd64.deb
linux系统上输出 png会有乱码：
解决：windows的 C:\Windows\Fonts 下的微软雅黑.ttf文件copy到 linux的/usr/share/fonts目录
如下为我的一段代码，将字体改成微软，同时输出png：

##################### # 折线图： # 兼容linux 系统 png文字乱码： #windows C:\Windows\Fonts 下的微软雅黑.ttf文件copy到 linux/usr/share/fonts目录 #####################import pygal import cairo from pygal.style import Style from datetime import datetime colors_dict = { 1:'#009688',# 2:'#F44336',# 3:'#3F51B5',# } def draw_line(data, x_label, y_title, title,colors_list): colors = [] for idx in colors_list: if idx in colors_dict: colors.append(colors_dict[idx]) else: colors.append(colors_dict[1]) colors = tuple(colors) custom_style = Style( background='#FFFFFF', plot_background='#FFFFFF', value_background='rgba(229, 229, 229, 1)', foreground='rgba(0, 0, 0, .87)', foreground_strong='rgba(0, 0, 0, 1)', foreground_subtle='rgba(0, 0, 0, .54)',# Monospaced font is highly encouraged font_family=( '"微软雅黑","华文细黑",Arial, Helvetica, sans-serif'),label_font_family=None, major_label_font_family=None, value_font_family=None, value_label_font_family=None, tooltip_font_family=None, title_font_family=None, legend_font_family=None, no_data_font_family=None,label_font_size=20, major_label_font_size=20, value_font_size=20, value_label_font_size=20, tooltip_font_size=14, title_font_size=30, legend_font_size=16, no_data_font_size=64,# Guide line dash array style guide_stroke_dasharray='6,1', major_guide_stroke_dasharray='6,1',opacity='.7', opacity_hover='.8',stroke_opacity='.8', stroke_opacity_hover='.9',transition='150ms', colors=colors, value_colors=(), ci_colors=())chart = pygal.Line(fill=True, style=custom_style,title=title,y_title=y_title, x_label_rotation=20, show_legend=False,width=1600,print_values=True, print_zeroes=False, print_values_position='top', show_minor_x_labels=False) chart.x_labels = x_label chart.x_labels_major = x_label[::5] for i in data: chart.add(i[0], i[1]) return chartif __name__=="__main__": data = https://www.it610.com/article/[('IE', [85.8, 84.6, 84.7, 74.5, 66, 58.6, 54.7, 44.8, 36.2, 26.6, 20.1])] x_label = ['2019-07-07', '2019-07-08', '2019-07-12', '2019-07-14', '2019-07-15','2019-07-16', '2019-07-17', '2019-07-18', '2019-07-19', '2019-07-20', '2019-07-21'] print(x_label) y_title = "嘿嘿嘿" title = "哈哈哈哈" save_path = 'test.png' chart = draw_line(data, x_label, y_title, title,[1]) chart.render_to_png(save_path)