Qt环境下读取csv数据进行矩阵运算

1. 读取csv数据

csv.h头文件

#ifndef CSV_H
#define CSV_H

#include <QString>
#include <QTextStream>
#include <QStringList>
#include <QList>
#include <QFile>


class CSVParser{
private:
    QList<QStringList> csvLines;
    QString seperator;
public:
    CSVParser();
    CSVParser(QString sep);
    QList<QStringList> read(QString filename);
    int write(QString filename, QList<QStringList> lines);

};

#endif // CSV_H
csv.cpp源程序
#include "csv.h"

CSVParser::CSVParser(){
    this->seperator = QString(",");
}

CSVParser::CSVParser(QString sep){
    this->seperator = sep;
}

QList<QStringList> CSVParser::read(QString filename){
    QFile file(filename);
    QString line;
    if(file.open(QFile::QIODevice::ReadOnly)){
        QTextStream stream(&file);
        while(!stream.atEnd()){
            line = stream.readLine();
            this->csvLines.append(line.split(this->seperator));
        }
        file.close();
    }
    return this->csvLines;
}

int CSVParser::write(QString filename, QList<QStringList> lines){
    QFile file(filename);
    QStringList line;
    if(file.open(QFile::QIODevice::WriteOnly)){
        QTextStream stream(&file);
        for(int i=0;i<lines.size();i++){
            line = lines[i];
            stream << line.join(this->seperator)<<"\n";
        }
        file.close();
        return 1;
    }
    return 0;
}
2. 使用矩阵运算库Eigen

在Qt环境中使用这个线性代数库,要在qmake中添加:

INCLUDEPATH += D:\Qt-libs\eigen

完整qmake:

QT += core
QT -= gui

CONFIG += c++11

TARGET = csv-mat-mult
CONFIG += console
CONFIG -= app_bundle
INCLUDEPATH += D:\Qt-libs\eigen
TEMPLATE = app

SOURCES += main.cpp \
    csv.cpp

HEADERS += \
    csv.h


主程序main.cpp为:

#include <iostream>
#include "csv.h"
#include <Eigen/Eigen>


int main()
{
    QString filename("aa.csv");
    CSVParser csvp(QString(","));
    QList<QStringList> lines;
    std::string str;
    const char* s;
    lines = csvp.read(filename);
    int m = lines.size();
    if(m!=0){
        int n = lines[0].size();
        if(n!=0){
            Eigen::MatrixXf mat(m,n);
            for(int i=0;i<m;i++){
                for(int j=0;j<n;j++){
                    str = lines[i][j].toStdString();
                    s = str.c_str();
                    mat(i,j) = atof(s);
                }
            }

            std::cout<<"mat = " <<std::endl<< mat<<std::endl;
            std::cout<<"mat*mat = " <<std::endl<< mat*mat<<std::endl;
        }
    }
    return 0;
}