python-matplotlib绘制多条曲线

1.项目背景

• 数据包中包含温度曲线数据，想利用python的matplotlib.pyplot绘制模块将数据曲线绘制出来。
• 涉及的python知识：1.文件操作 2.命令行参数解析 3.解析的字符转short，int 4.文件打包 5.曲线绘制

2.源码分析

2.1 2个字符转short，4个字符转int

2.2输入提示

import matplotlib.pyplot as plt
import numpy as np
import binascii 
import sys
import argparse
import getopt
import os
#1.解析焦温点数N
#2.解析曲线条数S
#3.解析曲线温度点个数

#将str转换为1个字节的数字
def ascii2Num_01(oneByte):
    hex_value = binascii.hexlify(oneByte)
    dec_value = int(hex_value,16)
    #print("asic:{},hex_value:{},dec_value:{}".format(oneByte,hex_value,dec_value))
    return dec_value

#将str转换为2个字节的数字
def ascii2Num_02(byte1,byte2):
    str = byte2 + byte1
    hex_value = binascii.hexlify(str)
    dec_value = int(hex_value,16)
    #print("str:{},hex_value:{},dec_value:{}".format(str,hex_value,dec_value))
    return dec_value
#将str转换为4个字节的数字
def ascii2Num_03(byte1,byte2,byte3,byte4):
    str = byte4 + byte3 + byte2 + byte1
    hex_value = binascii.hexlify(str)
    dec_value = int(hex_value,16)
    #print("str:{},hex_value:{},dec_value:{}".format(str,hex_value,dec_value))
    return dec_value


def inputHelp(argv):
    #print(argv)
    try:
      opts, args = getopt.getopt(argv,"hi:",["help","input="])
    except getopt.GetoptError:
      print('usage:readPackage.py -i ')
      sys.exit(2)
    for opt,arg in opts:
        #print("opt:{},arg:{}".format(opt,arg))
        if opt in ("-h","--help"):
            print("usage:readPackage.py -i ")
            sys.exit()
if __name__ == "__main__":
    inputHelp(sys.argv[1:])
    if len(sys.argv) == 3:
        if os.access(sys.argv[2],os.F_OK | os.R_OK):
            f = open(sys.argv[2],'rb')
            '''解析焦温点数N'''
            f.seek(0,2)
            fileSize = f.tell()
            f.seek(0,0) #回到文件开头
            f.seek(65,0)
            gearNum = ascii2Num_01(f.read(1))
            print("gearNum:{}".format(gearNum))

            '''解析w,h曲线温度点个数'''
            f.seek(75,0)
            disNum = ascii2Num_01(f.read(1))
            print("disNum:{}".format(disNum))
            w = ascii2Num_02(f.read(1),f.read(1))
            h = ascii2Num_02(f.read(1),f.read(1))
            curveTempNum = ascii2Num_02(f.read(1),f.read(1))
            gearArrayLen = ascii2Num_02(f.read(1),f.read(1))
            print("w:{},h:{},curveTempNum:{},gearArrayLen:{}".format(w,h,curveTempNum,gearArrayLen))
            '''曲线数据长度,K矩阵长度'''
            curveDataLen = ascii2Num_03(f.read(1),f.read(1),f.read(1),f.read(1))
            kLen = ascii2Num_03(f.read(1),f.read(1),f.read(1),f.read(1))
            print("curveDataLen:{},kLen:{}".format(curveDataLen,kLen))

            '''绘制曲线数据'''
            #将文件定位到曲线数组位置
            f.seek(216+1400+gearArrayLen,0)
            curve1X = []
            curve1Y = []
            for index in range(gearNum*disNum):
            #for index in range(2):
                curve1X.append([])
                curve1Y.append([])
                print("index={}".format(index))
                for x in range(curveTempNum):
                    tempValue = ascii2Num_02(f.read(1),f.read(1))
                    #print("hex_value: {},dec_value: {}".format(hex_value,dec_value))
                    if index ==0:
                        curve1X[0].append(x)
                    curve1Y[index].append(tempValue)
                plt.figure('curve')
                plt.plot(curve1X[0],curve1Y[index])  # plot绘制折线图
            pic_name = 'curve01.jpg'
            plt.savefig(pic_name)  #保存图象
            plt.show()
            f.close()  
        else:
            print("file is not exist!")
    else:
        print("输入不合法！")

3.可执行文件打包

参考下面的链接：
python打包exe程序参考

4.运行效果

• 执行命令：.\readPackage.py -i .\630_standard_high.raw
  

5.Qt QChart实现同样的绘制效果

• QT += core gui charts

#include 
#include 
    ui->setupUi(this);
    QChart* chart = new QChart;
    chart->setTitle("焦温-温度曲线");
    chart->createDefaultAxes();
    QValueAxis *axisX = new QValueAxis;
    axisX->setRange(0, 2300);
    axisX->setTickCount(24);
    axisX->setLabelFormat("%d");


    QValueAxis *axisY = new QValueAxis;
    axisY->setRange(500, 5000);
    axisY->setTickCount(10);
    axisY->setTitleText("温度/℃");
    axisY->setLabelFormat("%d");

    chart->addAxis(axisY,Qt::AlignLeft);
    chart->addAxis(axisX,Qt::AlignBottom);
    QSplineSeries *series = new QSplineSeries();
    series->setName("焦温1");
    series->append(0,500);
    series->append(1000,2000);
    series->append(2300,4500);

    QPen pen(QColor(0xff5566));
    series->setPen(pen);
    chart->addSeries(series);

    ui->chartView->setChart(chart);