Table of Contents

• CSV Reader
  • Performance Benchmark
  • Reader API
• CSV Writer
  • Writer API
• Compiling Tests
• Generating Single Header
• Contributing
• License

CSV Reader

#include 

int main() {
  csv2::Reader, 
               quote_character, 
               first_row_is_header,
               trim_policy::trim_whitespace> csv;
  if (csv.mmap("foo.csv")) {
    const auto header = csv.header();
    for (const auto row: csv) {
      for (const auto cell: row) {
        // Do something with cell value
        // std::string value;
        // cell.read_value(value);
      }
    }
  }
}

Performance Benchmark

This benchmark measures the average execution time (of 5 runs after 3 warmup runs) for

csv2

benchmark/main.cpp

cd benchmark
g++ -I../include -O3 -std=c++11 -o main main.cpp
./main 

Hardware

MacBook Pro (15-inch, 2019)
Processor: 2.4 GHz 8-Core Intel Core i9
Memory: 32 GB 2400 MHz DDR4
Operating System: macOS Catalina version 10.15.3

Results (as of 23 APR 2020)

| Dataset | File Size | Rows | Cols | Time | |:--- | ---:| ---:| ---:| ---:| | Denver Crime Data | 111 MB | 479,100 | 19 | 0.174s | | AirBnb Paris Listings | 196 MB | 141,730 | 96 | 0.289s | | 2015 Flight Delays and Cancellations | 574 MB | 5,819,079 | 31 | 1.047s | | StackLite: Stack Overflow questions | 870 MB | 17,203,824 | 7 | 1.505s | | Used Cars Dataset | 1.4 GB | 539,768 | 25 | 1.979s | | Title-Based Semantic Subject Indexing | 3.7 GB | 12,834,026 | 4 | 5.929s| | Bitcoin tweets - 16M tweets | 4 GB | 47,478,748 | 9 | 7.040s | | DDoS Balanced Dataset | 6.3 GB | 12,794,627 | 85 | 12.648s | | Seattle Checkouts by Title | 7.1 GB | 34,892,623 | 11 | 12.883s | | SHA-1 password hash dump | 11 GB | 2,62,974,241 | 2 | 19.505s | | DOHUI NOH scaled_data | 16 GB | 496,782 | 3213 | 32.780s |

Reader API

Here is the public API available to you:

template , 
          class quote_character = quote_character,
          class first_row_is_header = first_row_is_header,
          class trim_policy = trim_policy::trim_whitespace>
class Reader {
public:

  // Use this if you'd like to mmap and read from file
  bool mmap(string_type filename);
  // Use this if you have the CSV contents in std::string already
  bool parse(string_type contents);
  // Shape
  size_t rows() const;
  size_t cols() const;
  // Row iterator
  // If first_row_is_header, row iteration will start
  // from the second row
  RowIterator begin() const;
  RowIterator end() const;
  // Access the first row of the CSV
  Row header() const;
};

Here's the

Row

// Row class
class Row {
public:
  // Get raw contents of the row
  void read_raw_value(Container& value) const;

  // Cell iterator
  CellIterator begin() const;
  CellIterator end() const;
};

and here's the

Cell

// Cell class
class Cell {
public:
  // Get raw contents of the cell
  void read_raw_value(Container& value) const;

  // Get converted contents of the cell
  // Handles escaped content, e.g., 
  // """foo""" => ""foo""
  void read_value(Container& value) const;
};

CSV Writer

This library also provides a basic

csv2::Writer

#include 
#include 
#include 
using namespace csv2;

int main() {
    std::ofstream stream("foo.csv");
    Writer> writer(stream);
std::vector<:vector>&gt; rows = 
    {
        {"a", "b", "c"},
        {"1", "2", "3"},
        {"4", "5", "6"}
    };

writer.write_rows(rows);
stream.close();
}
</:vector>

Writer API

Here is the public API available to you:

template >
class Writer {
public:

  // Construct using an std::ofstream
  Writer(output_file_stream stream);
  // Use this to write a single row to file
  void write_row(container_of_strings row);
  // Use this to write a list of rows to file
  void write_rows(container_of_rows rows);

Compiling Tests

mkdir build && cd build
cmake -DCSV2_TEST=ON ..
make
cd test
./csv2_test

Generating Single Header

python3 utils/amalgamate/amalgamate.py -c single_include.json -s .

Contributing

Contributions are welcome, have a look at the CONTRIBUTING.md document for more information.

License

The project is available under the MIT license.