PGPLOT 的一个示例程序

简介

PGPLOT典型的应用主要是一些已知测定点的描绘和理论曲线的比对。

这里给出一个简单的例子程序，画出5个数据点，理论曲线为y=x^2。

代码

代码如下所示：

/**
 * Copyright (c) 2010-2017, Guo Shaoguang
 *
 * All rights reserved.
 *
 * @file shao_pgplot_y=x2.c
 * @author 	Guo Shaoguang
 * @email 	sgguo@shao.ac.cn
 * @date	2011.06.11
 * @version	v1.0
 *
 * @brief This file will y=x^2 using PGPLOT
 */

#include "../include/cpgplot.h"
#include <stdio.h>
#include <stdlib.h>

int main() {
    int i;
    static float xs[] = {1.0, 2.0, 3.0, 4.0, 5.0};
    static float ys[] = {1.0, 4.0, 9.0, 16.0, 25.0};
    float xr[100], yr[100];
    int n = sizeof(xr) / sizeof(xr[0]);

    printf("Now begin to plot ...\n");

    /// 1. Enable the PGPLOT and setting the device
    if (cpgbeg(0, "?", 1, 1) != 1)
        return EXIT_FAILURE;

    /// 2. Setting the axis of x and y including label
    cpgenv(0.0, 10.0, 0.0, 20.0, 0, 1);
    cpglab("(x)", "(y)", "y = x\\u2\\d");
    cpgiden();

    /// 3. Begin plot points / lines
    cpgpt(5, xs, ys, 9);

    for (i = 0; i < n; i++) {
        xr[i] = 0.1 * i;
        yr[i] = xr[i] * xr[i];
    }

    cpgline(n,xr,yr);

    /// 4. Close the PGPLOT
    cpgend();

    return EXIT_SUCCESS;
}

结果