C++ 调用Matlab画图

劳动节闲来无事，写了一天程序，just for fun.

看，这是C++调用Matlab画图的一段程序。暂时不想多解释了，有兴趣的话，看看下面的代码吧。

以下几段代码由上到下，越来越旧。最上面的是最新更新的版本。

#include <iostream>#include <vector>#include <string>#include <algorithm>#include <cmath>using namespace std;#include <Eigen/Eigen>#include <engine.h>#include <boost/algorithm/string.hpp>class MatArray{public:    MatArray() : _data(NULL){}    MatArray(size_t irows, size_t icols){        resize(irows, icols);    }    MatArray(const MatArray &obj){        if (obj._data){            _data = mxCreateDoubleMatrix(obj.rows(), obj.cols(), mxREAL);            memcpy(this->ptr(), obj.ptr(), sizeof(double)*rows()*cols());        }        else{            _data = NULL;        }    }    ~MatArray(){ mxDestroyArray(_data); _data = NULL; }    inline size_t rows() const { return _data ? mxGetM(_data) : 0; }    inline size_t cols() const { return _data ? mxGetN(_data) : 0; }    inline double* ptr() const { return _data ? mxGetPr(_data) : NULL; }    bool resize(size_t irows, size_t icols){        if (!_data){            _data = mxCreateDoubleMatrix(irows, icols, mxREAL);            return (_data != NULL);        }        if (rows() == irows || cols() == icols){            return true;        }        mxDestroyArray(_data);        _data = mxCreateDoubleMatrix(irows, icols, mxREAL);        return (_data != NULL);    }    int put(Engine *ep, const char* var_name){        return engPutVariable(ep, var_name, _data);    }    template<class EigenMat = Eigen::MatrixXf>    void copy_from_eigen(const EigenMat &emat){        if (emat.rows()*emat.cols() == 0){            mxDestroyArray(_data); _data = NULL;        }        resize(emat.rows(), emat.cols());        for (int c = 0; c < emat.cols(); c++){            for (int r = 0; r < emat.rows(); r++){                (*this)[r + c*(int)(emat.rows())] = emat(r, c);            }        }    }    inline double& operator[](int i){        return ptr()[i];    }private:    mxArray *_data;};string rndcolor(){    string color = "[";    color += to_string((rand() % 256) / 255.) + ",";    color += to_string((rand() % 256) / 255.) + ",";    color += to_string((rand() % 256) / 255.) + "]";    return color;}class Matlab{private:    Matlab(const Matlab &obj){}public:    Matlab(){        _engine = engOpen(NULL);        if (!_engine){            cerr << "failed to open MATLAB engine!" << endl;        }        else{            cout << "MATLAB has been started successfully!" << endl;        }    }    ~Matlab(){        // if you are testing algorithm, you are encouraged to keep the line below bing committed.        //engClose(_engine); _engine = NULL;    }    // line_spec : "LineStyle" + "Marker" + "Color", e.g. "-or"    // for line    // "LineStyle" = {"none", "-", ":", "-."}    // "LineWidth" = 0.5    // "Color" = {[0 0.4470 0.7410] (default) | RGB triplet | {y,m,c,r,g,b,w,k} | 'none'}    // for Marker    // "Marker" = {"none", "o", "+", "*", ".", "x", "s", "d", "^", "v", ">", "<", 'p', 'h'}    // "MarkerEdgeColor" = 'auto' (default) | 'none' | RGB triplet | {y,m,c,r,g,b,w,k}    // "MarkerFaceColor" = 'auto' (default) | 'none' | RGB triplet | {y,m,c,r,g,b,w,k}    // "MarkerSize" = 6    template<class TMatX = Eigen::MatrixXf, class TMatY = Eigen::MatrixXf>    int plot(const TMatX &X, const TMatY &Y,        string nm0  = "",        string nm1  = "", string nm2  = "",        string nm3  = "", string nm4  = "",        string nm5  = "", string nm6  = "",        string nm7  = "", string nm8  = "",        string nm9  = "", string nm10 = "",        string nm11 = "", string nm12 = "",        string nm13 = "", string nm14 = ""        ){        MatArray MX, MY;        MX.copy_from_eigen(X); MX.put(_engine, "MX");        MY.copy_from_eigen(Y); MY.put(_engine, "MY");        string plot_code = "MX, MY";        string code;#define EVL_CODE(_ARG0,_ARG1) code = var_plot_code(nm##_ARG0, nm##_ARG1); if(code != ""){ plot_code += ", " + code;}        code = var_plot_code(nm0, "");        if (code != ""){            plot_code += ", " + code;            EVL_CODE(1, 2);            EVL_CODE(3, 4);            EVL_CODE(5, 6);            EVL_CODE(7, 8);            EVL_CODE(9, 10);            EVL_CODE(11, 12);            EVL_CODE(13, 14);        }        else{            EVL_CODE(0, 1);            EVL_CODE(2, 3);            EVL_CODE(4, 5);            EVL_CODE(6, 7);            EVL_CODE(8, 9);            EVL_CODE(10, 11);            EVL_CODE(12, 13);        }#undef EVL_CODE        plot_code = "plot(" + plot_code + ");";        cout << plot_code << endl;        exec(plot_code);        return 0;    }    // line_spec : "LineStyle" + "Marker" + "Color", e.g. "-or"    // for line    // "LineStyle" = {"none", "-", ":", "-."}    // "LineWidth" = 0.5    // "Color" = {[0 0.4470 0.7410] (default) | RGB triplet | {y,m,c,r,g,b,w,k} | 'none'}    // for Marker    // "Marker" = {"none", "o", "+", "*", ".", "x", "s", "d", "^", "v", ">", "<", 'p', 'h'}    // "MarkerEdgeColor" = 'auto' (default) | 'none' | RGB triplet | {y,m,c,r,g,b,w,k}    // "MarkerFaceColor" = 'auto' (default) | 'none' | RGB triplet | {y,m,c,r,g,b,w,k}    // "MarkerSize" = 6    template<class TMatX = Eigen::MatrixXf, class TMatY = Eigen::MatrixXf, class TMask = Eigen::MatrixXi>    int plot_mask(const TMatX &X, const TMatY &Y, const TMask &mask,        string nm0  = "",        string nm1  = "", string nm2  = "",        string nm3  = "", string nm4  = "",        string nm5  = "", string nm6  = "",        string nm7  = "", string nm8  = "",        string nm9  = "", string nm10 = "",        string nm11 = "", string nm12 = "",        string nm13 = "", string nm14 = ""        ){        MatArray MX, MY, MS;        MX.copy_from_eigen(X); MX.put(_engine, "MX");        MY.copy_from_eigen(Y); MY.put(_engine, "MY");        MS.copy_from_eigen(mask); MS.put(_engine, "MS");        string plot_code = "MX(MS>0), MY(MS>0)";        string code;#define EVL_CODE(_ARG0,_ARG1) code = var_plot_code(nm##_ARG0, nm##_ARG1); if(code != ""){ plot_code += ", " + code;}        code = var_plot_code(nm0, "");        if (code != ""){            plot_code += ", " + code;            EVL_CODE(1, 2);            EVL_CODE(3, 4);            EVL_CODE(5, 6);            EVL_CODE(7, 8);            EVL_CODE(9, 10);            EVL_CODE(11, 12);            EVL_CODE(13, 14);        }        else{            EVL_CODE(0, 1);            EVL_CODE(2, 3);            EVL_CODE(4, 5);            EVL_CODE(6, 7);            EVL_CODE(8, 9);            EVL_CODE(10, 11);            EVL_CODE(12, 13);        }#undef EVL_CODE        plot_code = "plot(" + plot_code + ");";        cout << plot_code << endl;        exec(plot_code);        return 0;    }    string var_plot_code(string nm, string var){        boost::trim(nm); boost::trim(var);        if (nm == ""){            return "";        }        string code = "'" + nm + "'";        if (var == ""){            return (nm[0] < 'A' || nm[0] > 'Z') ? code : "";        }        if (nm == "LineStyle" || nm == "Marker"){ // string            // 'LineStyle', '-'            return code + ", '" + var + "'";        }        if (nm == "LineWidth" || nm == "MarkerSize"){ // positive number            // 'LineWidth', 0.5            return code + ",  " + var;        }        if (nm == "Color" || nm == "MarkerEdgeColor" || nm == "MarkerFaceColor"){            if (var[0] == '['){                return code + ",  " + var;            }            else{                return code + ", '" + var + "'";            }        }        return "";    }    int exec(string cmd){        return engEvalString(_engine, cmd.c_str());    }private:    Engine *_engine;};Matlab mbeng;int main(int argc, char** argv){    // random circles    Eigen::ArrayXXf data;    data = data.Random(1000, 2);    //mbeng.exec("figure(1); clf;");    mbeng.plot(data.col(0), data.col(1), "o", "MarkerFaceColor", "[0,0,0]", "MarkerEdgeColor", "[0,0,0]");    mbeng.exec("axis tight;");    // different colors    int K = 4;    Eigen::ArrayXXi clid;    clid = Eigen::abs(clid.Random(1000, 1));    for (int i = 0; i < clid.rows(); i++){        clid(i, 0) = clid(i, 0) % K;    }       mbeng.exec("figure(2); clf;");    for (int k = 0; k < K; k++){        string colors = rndcolor();        mbeng.plot_mask(data.col(0), data.col(1), (clid == k), "o", "MarkerFaceColor", colors, "MarkerEdgeColor", colors, "MarkerSize", "5");        mbeng.exec("hold on;");    }    mbeng.exec("hold off;");    mbeng.exec("axis tight;");    // plot line    Eigen::ArrayXf X;    Eigen::ArrayXf Y;    X = X.LinSpaced(30,-3.1415926f, 3.1415926f);    Y = X.sin()*X.cos();    mbeng.exec("figure(3);");    mbeng.plot(X, Y, "LineStyle", "-.", "Marker", "o", "MarkerSize", "5", "MarkerFaceColor", "[0,1,0]");    mbeng.exec("axis tight;");    return EXIT_SUCCESS;}

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#include <iostream>#include <vector>#include <string>#include <algorithm>#include <cmath>using namespace std;#include <Eigen/Eigen>#include <engine.h>class MatArray{public:    MatArray() : _data(NULL){}    MatArray(size_t irows, size_t icols){        resize(irows, icols);    }    MatArray(const MatArray &obj){        if (obj._data){            _data = mxCreateDoubleMatrix(obj.rows(), obj.cols(), mxREAL);            memcpy(this->ptr(), obj.ptr(), sizeof(double)*rows()*cols());        }        else{            _data = NULL;        }    }    ~MatArray(){ mxDestroyArray(_data); _data = NULL; }    inline size_t rows() const { return _data ? mxGetM(_data) : 0; }    inline size_t cols() const { return _data ? mxGetN(_data) : 0; }    inline double* ptr() const { return _data ? mxGetPr(_data) : NULL; }    bool resize(size_t irows, size_t icols){        if (!_data){            _data = mxCreateDoubleMatrix(irows, icols, mxREAL);            return (_data != NULL);        }        if (rows() == irows || cols() == icols){            return true;        }        mxDestroyArray(_data);        _data = mxCreateDoubleMatrix(irows, icols, mxREAL);        return (_data != NULL);    }    int put(Engine *ep, const char* var_name){        return engPutVariable(ep, var_name, _data);    }    template<class EigenMat = Eigen::MatrixXf>    void copy_from_eigen(const EigenMat &emat){        if (emat.rows()*emat.cols() == 0){            mxDestroyArray(_data); _data = NULL;        }        resize(emat.rows(), emat.cols());        for (int c = 0; c < emat.cols(); c++){            for (int r = 0; r < emat.rows(); r++){                (*this)[r + c*(int)(emat.rows())] = emat(r, c);            }        }    }    inline double& operator[](int i){        return ptr()[i];    }private:    mxArray *_data;};string rndcolor(){    string color = "[";    color += to_string((rand() % 256) / 255.) + ",";    color += to_string((rand() % 256) / 255.) + ",";    color += to_string((rand() % 256) / 255.) + "]";    return color;}class Matlab{private:    Matlab(const Matlab &obj){}public:    Matlab(){        _engine = engOpen(NULL);        if (!_engine){            cerr << "failed to open MATLAB engine!" << endl;        }        else{            cout << "MATLAB has been started successfully!" << endl;        }    }    ~Matlab(){        // if you are testing algorithm, you are encouraged to keep the line below bing committed.        //engClose(_engine); _engine = NULL;    }    template<class TMatX = Eigen::MatrixXf, class TMatY = Eigen::MatrixXf>    int plot(const TMatX &X, const TMatY &Y, string line_spec = "", int figure_id = 1, bool hold_on = false){        MatArray MX, MY, ID;        MX.copy_from_eigen(X); MX.put(_engine, "MX");        MY.copy_from_eigen(Y); MY.put(_engine, "MY");        ID.resize(1, 1); ID[0] = figure_id; ID.put(_engine, "ID");        string plot_code = " figure(ID); plot(MX, MY";        if (line_spec != ""){            plot_code = plot_code + "," + line_spec;        }        plot_code += ");";        plot_code += hold_on ? "hold on;" : "hold off;";        return engEvalString(_engine, plot_code.c_str());    }    template<class TMatX = Eigen::MatrixXf, class TMatY = Eigen::MatrixXf, class TMatC = Eigen::MatrixXf>    int plot(const TMatX &X, const TMatY &Y, const TMatC &C, int K, int figure_id = 1, int marker_size = 5, string line_and_marker = "o"){        MatArray MX, MY, MC, ID;        MX.copy_from_eigen(X); MX.put(_engine, "MX");        MY.copy_from_eigen(Y); MY.put(_engine, "MY");        MC.copy_from_eigen(C); MC.put(_engine, "MC");        ID.resize(1, 1); ID[0] = figure_id; ID.put(_engine, "ID");        exec("figure(ID); clf;");        for (int k = 0; k < K; k++){            string rdc = rndcolor();            exec(string("idx = MC==") + to_string(k) + ";");            exec("plot(MX(idx), MY(idx), '" + line_and_marker + "', 'MarkerEdgeColor', " + rdc + ",'MarkerFaceColor'," + rdc + ", 'MarkerSize'," + to_string(marker_size) + "); hold on;");        }        exec("hold off;");        return 0;    }    template<class TMatX = Eigen::MatrixXf, class TMatY = Eigen::MatrixXf>    int plot(const TMatX &X, const TMatY &Y, int figure_id = 1, int marker_size = 5, string line_and_marker = "-"){        MatArray MX, MY, ID;        MX.copy_from_eigen(X); MX.put(_engine, "MX");        MY.copy_from_eigen(Y); MY.put(_engine, "MY");        ID.resize(1, 1); ID[0] = figure_id; ID.put(_engine, "ID");        string rdc = rndcolor();        exec("figure(ID); clf;");        exec("plot(MX, MY, '" + line_and_marker + "', 'MarkerEdgeColor', " + rdc + ",'MarkerFaceColor'," + rdc + ", 'MarkerSize'," + to_string(marker_size) + "); hold on;");        exec("hold off;");        return 0;    }       int exec(string cmd){        return engEvalString(_engine, cmd.c_str());    }private:    Engine *_engine;};#if 1int main(int argc, char** argv){    Matlab mbeng;    // random circles    Eigen::ArrayXXf data;    data = data.Random(1000, 2);    mbeng.plot(data.col(0), data.col(1), 1, 5, "o");    mbeng.exec("axis tight;");    // different colors    int K = 4;    Eigen::ArrayXXi clid;    clid = Eigen::abs(clid.Random(1000, 1));    for (int i = 0; i < clid.rows(); i++){        clid(i,0) = clid(i,0) % K;    }       mbeng.plot(data.col(0), data.col(1), clid, K, 2);    mbeng.exec("axis tight;");    // plot line    Eigen::ArrayXXf X(1000,1);    Eigen::ArrayXXf Y(1000,1);    float fpi = 3.1415926f;    float sstep = fpi*2 / 1000.f;    for (int i = 0; i < X.rows(); i++){        X(i, 0) = -3.1415926f + i*sstep;        Y(i, 0) = sin(X(i,0))*cos(X(i,0));    }    mbeng.plot(X, Y, 3, 5, " - ");    mbeng.exec("axis tight;");    return EXIT_SUCCESS;}#endif

跑一下：

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#include <iostream>#include <vector>#include <string>#include <algorithm>#include <cmath>#include <ctime>using namespace std;#include <Eigen/Eigen>#include <engine.h>class MatArray{public:    MatArray() : _data(NULL){}    MatArray(size_t irows, size_t icols){        resize(irows, icols);    }    MatArray(const MatArray &obj){        if (obj._data){            _data = mxCreateDoubleMatrix(obj.rows(), obj.cols(), mxREAL);            memcpy(this->ptr(), obj.ptr(), sizeof(double)*rows()*cols());        }        else{            _data = NULL;        }    }    ~MatArray(){ mxDestroyArray(_data); _data = NULL; }    inline size_t rows() const { return _data? mxGetM(_data):0; }    inline size_t cols() const { return _data? mxGetN(_data):0; }    inline double* ptr() const { return _data? mxGetPr(_data):NULL; }    bool resize(size_t irows, size_t icols){        if (!_data){            _data = mxCreateDoubleMatrix(irows, icols, mxREAL);            return (_data != NULL);        }        if (rows() == irows || cols() == icols){            return true;        }        mxDestroyArray(_data);         _data = mxCreateDoubleMatrix(irows, icols, mxREAL);        return (_data != NULL);    }    int put(Engine *ep, const char* var_name){        return engPutVariable(ep, var_name, _data);    }    template<class EigenMat=Eigen::MatrixXf>    void copy_from_eigen(const EigenMat &emat){        if (emat.rows()*emat.cols() == 0){            mxDestroyArray(_data); _data = NULL;                    }        resize(emat.rows(), emat.cols());        for (int c = 0; c < emat.cols(); c++){            for (int r = 0; r < emat.rows(); r++){                (*this)[r + c*emat.rows()] = emat(r, c);            }        }    }    inline double& operator[](int i){        return ptr()[i];    }private:    mxArray *_data;};class Matlab{private:    Matlab(const Matlab &obj){}public:    Matlab(){         _engine = engOpen(NULL);         if (!_engine){             cerr << "failed to open MATLAB engine!" << endl;         }         else{             cout << "MATLAB has been started successfully!" << endl;         }           }    ~Matlab(){        // if you are testing algorithm, you are encouraged to keep the line below bing committed.        //engClose(_engine); _engine = NULL;    }    template<class TMatX = Eigen::MatrixXf, class TMatY = Eigen::MatrixXf>    int plot(const TMatX &X, const TMatY &Y, string line_spec = "", int figure_id = 1, bool hold_on = false){        MatArray MX, MY, ID;        MX.copy_from_eigen(X); MX.put(_engine, "MX");        MY.copy_from_eigen(Y); MY.put(_engine, "MY");        ID.resize(1, 1); ID[0] = figure_id; ID.put(_engine, "ID");        string plot_code = " figure(ID); plot(MX, MY";        if (line_spec != ""){            plot_code = plot_code + "," + line_spec;        }        plot_code += ");";        plot_code += hold_on ? "hold on;" : "hold off;";        return engEvalString(_engine, plot_code.c_str());    }       int exec(string cmd){        return engEvalString(_engine, cmd.c_str());    }private:    Engine *_engine;};string rndcolor(){    string color = "[";    color += to_string((rand() % 256) / 255.) + ",";    color += to_string((rand() % 256) / 255.) + ",";    color += to_string((rand() % 256) / 255.) + "]";    return color;}int main(int argc, char** argv){    Eigen::MatrixXf data;    srand((unsigned int)time(0));    data = data.Random(1000, 2);    Matlab mateng;    //mateng.exec("clear all; close all;");    mateng.plot(data.col(0), data.col(1), string("'s',") + "'MarkerEdgeColor'," + rndcolor() + ",'MarkerFaceColor'," + rndcolor() + ", 'MarkerSize', 5", 1, true);    return EXIT_SUCCESS;}

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执行一下！看看结果！