Quick CSV

quickcsv is an easy-to-use C++ reader and parser library for utf8 CSV file. It supports C++17 (and later), is header-only and comes with a basic test suite.

Installation

Method 1: Simply copy include/quickcsv.hpp to your project/include directory and include it.

Method 2: by your CMakeLists.txt file

# CMakeLists.txt
include(FetchContent)

FetchContent_Declare(
  quickcsv
  GIT_REPOSITORY https://github.com/GreyRaphael/quickcsv.git
  GIT_TAG v1.1.1)
FetchContent_MakeAvailable(quickcsv)
# Adds quickcsv::quickcsv

add_executable(your_project main.cpp)
target_link_libraries(your_project PRIVATE quickcsv::quickcsv)

Usage

auto [col1, col2] = quickcsv::read_csv<col1_type, col2_type, col3_type>(filename, parameter_struct);

example1: Reading all data from the following examples/csv/en.csv.

symbol	open	high	low	close	volume
AAPL	123.75	127.93	122.790001	127.790001	116307900
MSFT	235.899994	237.470001	233.149994	236.940002	25324000
IBM	115.057358	116.940727	114.588913	115.430206	5977367
TSLA	230.036667	239.666672	228.350006	239.476669	81408600

symbol,open,high,low,close,volume
AAPL,123.750000,127.930000,122.790001,127.790001,116307900
MSFT,235.899994,237.470001,233.149994,236.940002,25324000,
IBM,115.057358,116.940727,114.588913,115.430206,5977367
TSLA,230.036667,239.666672,228.350006,239.476669,81408600

#include <cassert>  // for assert
#include <iostream>
#include <vector>

#include "quickcsv.hpp"

void test_example1(std::string const& filename) {
    // get all columns: symbol,open,high,low,close,volume
    // the parsing types is: <std::string, double, double, double, double, int> respectively
    auto [symbol_vec, open_vec, high_vec, low_vec, close_vec, volume_vec] = quickcsv::read_csv<std::string, double, double, double, double, int>(filename);

    assert(typeid(volume_vec) == typeid(std::vector<int>));

    size_t vect_size = symbol_vec.size();
    for (unsigned i = 0; i < vect_size; ++i) {
        std::cout << symbol_vec[i] << '\t';
        std::cout << open_vec[i] << '\t';
        std::cout << high_vec[i] << '\t';
        std::cout << low_vec[i] << '\t';
        std::cout << close_vec[i] << '\t';
        std::cout << volume_vec[i] << '\n';
    }
}

int main(){
    test_example1("csv/en.csv");
}

# output
AAPL    123.75  127.93  122.79  127.79  116307900
MSFT    235.9   237.47  233.15  236.94  25324000
IBM     115.057 116.941 114.589 115.43  5977367
TSLA    230.037 239.667 228.35  239.477 81408600

example2: Reading first 3 columns from the following examples/csv/en.csv

symbol,open,high,low,close,volume
AAPL,123.750000,127.930000,122.790001,127.790001,116307900
MSFT,235.899994,237.470001,233.149994,236.940002,25324000,
IBM,115.057358,116.940727,114.588913,115.430206,5977367
TSLA,230.036667,239.666672,228.350006,239.476669,81408600

#include <iostream>

#include "quickcsv.hpp"

void test_example2(std::string const& filename) {
    // get first three colums: symbol,open,high
    // the parsing types is: <std::string, double, int> related to column index
    auto [symbol_vec, close_vec, volume_vec] = quickcsv::read_csv<std::string, double, int>(filename);

    for (unsigned i = 0; i < symbol_vec.size(); ++i) {
        std::cout << symbol_vec[i] << '\t' << close_vec[i] << '\t' << volume_vec[i] << '\n';
    }
}

int main(){
    test_example2("csv/en.csv");
}

# output
AAPL    123.75  127
MSFT    235.9   237
IBM     115.057 116
TSLA    230.037 239

example3: Reading specified columns from the following examples/csv/en.csv with parameters

symbol,open,high,low,close,volume
AAPL,123.750000,127.930000,122.790001,127.790001,116307900
MSFT,235.899994,237.470001,233.149994,236.940002,25324000,
IBM,115.057358,116.940727,114.588913,115.430206,5977367
TSLA,230.036667,239.666672,228.350006,239.476669,81408600

#include <iostream>

#include "quickcsv.hpp"

void test_example3(std::string const& filename) {
    // get specified columns: symbol,close,volume
    // the parsing types is: <std::string, double, int> related to column index
    // specify parameters: sep, skiprows, usecols
    quickcsv::Param parameters{
        .sep = ',',
        .skiprows = 0,
        .usecols = {"symbol", "close", "volume"},
    };
    auto [symbol_vec, close_vec, volume_vec] = quickcsv::read_csv<std::string, double, int>(filename, parameters);
    for (unsigned i = 0; i < symbol_vec.size(); ++i) {
        std::cout << symbol_vec[i] << '\t' << close_vec[i] << '\t' << volume_vec[i] << '\n';
    }
}

int main(){
    test_example3("csv/en.csv");
}

# output
AAPL    127.79  116307900
MSFT    236.94  25324000
IBM     115.43  5977367
TSLA    239.477 81408600

example4: Reading specified columns from the following examples/csv/empty_cells.csv with parameters & NAN values

symbol	open	high	low	close	volume
AAPL	123.75	127.93	122.790001	127.790001	116307900
	235.899994	237.470001	233.149994	236.940002	25324000
IBM	115.057358	116.940727	114.588913	115.430206
TSLA	230.036667	239.666672	228.350006		81408600

;examples/csv/empty_cells.csv
symbol,open,high,low,close,volume
AAPL,123.750000,127.930000,122.790001,127.790001,116307900
,235.899994,237.470001,233.149994,236.940002,25324000
IBM,115.057358,116.940727,114.588913,115.430206,
TSLA,230.036667,239.666672,228.350006,,81408600

#include <iostream>

#include "quickcsv.hpp"

void test_example4(std::string const& filename) {
    // get specified columns: symbol,close,volume
    // the parsing types is: <std::string, double, int> related to column index
    // specify parameters: sep, skiprows, usecols
    // specify empty value(also are default value): na_value of integer = 0; na_value of float = NAN
    quickcsv::Param parameters{
        .sep = ',',
        .skiprows = 1,
        .usecols = {"symbol", "close", "volume"},
    };
    quickcsv::EMPTY_FLOAT = NAN;
    quickcsv::EMPTY_INT = 0;
    auto [symbol_vec, close_vec, volume_vec] = quickcsv::read_csv<std::string, double, int>(filename, parameters);
    for (unsigned i = 0; i < symbol_vec.size(); ++i) {
        std::cout << symbol_vec[i] << '\t' << close_vec[i] << '\t' << volume_vec[i] << '\n';
    }
}

int main(){
    test_example4("csv/empty_cells.csv");
}

# output
AAPL    127.79  116307900
        236.94  25324000
IBM     115.43  0
TSLA    nan     81408600

example5: Reading chinese symbols from the following examples/csv/cn.csv

stockcode,name,close,volume
000725,京东方A,4.32,592100000
600519,贵州茅台,1690.03,1520000
300750,宁德时代,222.25,9810000
688981,中芯国际,49.38,28340000

#include <iostream>

#include "quickcsv.hpp"

void test_example5(std::string const& filename) {
    auto [stockcode_vec, name_vec, close_vec, volume_vec] = quickcsv::read_csv<std::string, std::string, double, int>(filename);

    for (unsigned i = 0; i < stockcode_vec.size(); ++i) {
        std::cout << stockcode_vec[i] << '\t';
        std::cout << name_vec[i] << '\t';
        std::cout << close_vec[i] << '\t';
        std::cout << volume_vec[i] << '\n';
    }
}

int main(){
    test_example5("csv/cn.csv");
}

# output
000725  京东方A 4.32    592100000
600519  贵州茅台        1690.03 1520000
300750  宁德时代        222.25  9810000
688981  中芯国际        49.38   28340000