python学习（一）：画幅好画

准备工作：
1.python34+sublime
2.准备太阳黑子数据predict.txt
3.安装tomcat，并将predict.txt置于根目录下

sunspots_roto.py

#第一行就与python2不同#原文：from urllib import urlopenfrom urllib.request import urlopenfrom reportlab.graphics.shapes import *from reportlab.graphics.charts.lineplots import LinePlot from reportlab.graphics.charts.textlabels import Label from reportlab.graphics import renderPDF#http://localhost:8080/predict.txtURL = 'http://localhost:8080/predict.txt'#原文：COMMENT_CHARS = '#:',txt数据中没有:，因此不加也行的COMMENT_CHARS = '#'drawing=Drawing(400,200)data = []for line in urlopen(URL).readlines():    #原文：not line[0] in COMMENT_CHARS;    #不使用decode的话，line的类型为<class 'bytes'>，    #错误提示：TypeError: 'str' does not support the buffer interface    line = line.decode()    if not line.isspace() and not line[0] in COMMENT_CHARS:        data.append([float(n) for  n in line.split()])pred = [row[2]-40 for row in data]  high = [row[3]-40 for row in data]  low = [row[4]-40 for row in data]  times = [row[0] + row[1]/12 for row in data]  lp = LinePlot()lp.x = 50lp.y = 50lp.height = 125lp.width = 300#原文：lp.data =[zip(times,pred),zip(times,high),zip(times,low)]，#不使用tuple转换会报错，#错误提示：TypeError: object of type 'zip' has no len()la =tuple(zip(times,pred))lb =tuple(zip(times,high))lc = tuple(zip(times,low))lp.data =[la,lb,lc]lp.lines[0].strokeColor= colors.red lp.lines[1].strokeColor= colors.blue lp.lines[2].strokeColor= colors.green drawing.add(lp)drawing.add(String(250,150,'Sunspots',fontSize =14,fillColor=colors.red))renderPDF.drawToFile(drawing,'report2.pdf','ssss')

运行效果：