码农code之路QCustomPlot是一个基于Qt C++的图形库，用于绘制和数据可视化 – 制作漂亮的2D图 – 曲线图、趋势图、坐标图、柱状图等。
有详细的例程和帮助文档，使用方便。
一、下载
到官网https://www.qcustomplot.com/index.php/download下载最新版本
二、安装帮助文档
1.下载后解压，有如下文档
（1）帮助文档：documentation
（2）例程：examples
（3）源文件：qcustomplot.cpp和qcustomplot.h
2.将帮助文档qcustomplot.qch，复制到QT目录下，例如E:\Qt\Docs\Qt-5.13.0（根据自己QT的安装位置）
3.打开QT，工具->选项->帮助->添加
4.选择qcustomplot.qch，帮助文档就安装好了
三、测试
1.新建工程，customplot.cpp和qcustomplot.h复制到工程文件里，并在项目里qcustomplot.cpp和qcustomplot.h添加进来，.pro里添加
QT += printsupport
2.打开.ui文件，拖入一个widget控件，右键提升
3.输入QcustomPlot，点添加，再点提升，编译一下，看有没错误。
4.在构造函数里添加测试代码
1 MainWindow::MainWindow(QWidget *parent) :
2 QMainWindow(parent),
3 ui(new Ui::MainWindow)
4 {
5 ui->setupUi(this);
6
7 QCustomPlot* customPlot = ui->customPlot;
8 // add two new graphs and set their look:
9 customPlot->addGraph();
10 customPlot->graph(0)->setPen(QPen(Qt::blue)); // line color blue for first graph
11 customPlot->graph(0)->setBrush(QBrush(QColor(0, 0, 255, 20))); // first graph will be filled with translucent blue
12 customPlot->addGraph();
13 customPlot->graph(1)->setPen(QPen(Qt::red)); // line color red for second graph
14 // generate some points of data (y0 for first, y1 for second graph):
15 QVector<double> x(251), y0(251), y1(251);
16 for (int i=0; i<251; ++i)
17 {
18 x[i] = i;
19 y0[i] = qExp(-i/150.0)*qCos(i/10.0); // exponentially decaying cosine
20 y1[i] = qExp(-i/150.0); // exponential envelope
21 }
22 // configure right and top axis to show ticks but no labels:
23 // (see QCPAxisRect::setupFullAxesBox for a quicker method to do this)
24 customPlot->xAxis2->setVisible(true);
25 customPlot->xAxis2->setTickLabels(false);
26 customPlot->yAxis2->setVisible(true);
27 customPlot->yAxis2->setTickLabels(false);
28 // make left and bottom axes always transfer their ranges to right and top axes:
29 connect(customPlot->xAxis, SIGNAL(rangeChanged(QCPRange)), customPlot->xAxis2, SLOT(setRange(QCPRange)));
30 connect(customPlot->yAxis, SIGNAL(rangeChanged(QCPRange)), customPlot->yAxis2, SLOT(setRange(QCPRange)));
31 // pass data points to graphs:
32 customPlot->graph(0)->setData(x, y0);
33 customPlot->graph(1)->setData(x, y1);
34 // let the ranges scale themselves so graph 0 fits perfectly in the visible area:
35 customPlot->graph(0)->rescaleAxes();
36 // same thing for graph 1, but only enlarge ranges (in case graph 1 is smaller than graph 0):
37 customPlot->graph(1)->rescaleAxes(true);
38 // Note: we could have also just called customPlot->rescaleAxes(); instead
39 // Allow user to drag axis ranges with mouse, zoom with mouse wheel and select graphs by clicking:
40 customPlot->setInteractions(QCP::iRangeDrag | QCP::iRangeZoom | QCP::iSelectPlottables);
41 }
5.运行，没错误能看到如下波形。
来源：https://blog.csdn.net/yxy244
