Stats

stats is a CLI tool to compute basic statistics on a list of numbers.
This is a project for me to learn C++, so it is probably not the most efficient, but it runs fast enough and should be usable by anyone.

Installation

For the moment there are no releases, but since the code only uses the standard library it should be very easy to build on your local machine.

$ g++ -std=c++11 -o stats main.cpp

There is a cmake file automatically generated by my IDE, you can also use it to build the executable (although it might be a little overkill :p)

Usage

stats is meant to be used on standard input only, I might add the option to read from a file later.
stats expects a list of numbers, one per line, as input. It is meant to be used in conjunction with other tools such as cut to parse more complex files such as .csv.

Basic examples

# Create list of numbers
$ echo "1\n2\n3\n4\n5\n6\n7\n8\n9\n10" > test.data

# Get basic statistics on list of numbers 
$ cat test.data | stats

  Mean:     5.5
  Variance: 8.25 (2.87228 SD)
  Min:      1
  Max:      10
  Count:    10

# Format output as json
$ cat test.data | stats --json

  {
  	  "mean": 5.5,
	  "variance": 8.25,
	  "stdev": 2.87228,
	  "min": 1,
	  "max": 10,
	  "count": 10
  }

# Compute median and quartiles
$ cat test.data | stats --quartiles

  Mean:     5.5
  Variance: 8.25 (2.87228 SD)
  Min:      1
  Max:      10
  Count:    10
  Q1:       4
  Median:   6
  Q3:       9

# Download csv file
$ curl "https://gist.githubusercontent.com/netj/8836201/raw/6f9306ad21398ea43cba4f7d537619d0e07d5ae3/iris.csv" > iris.csv

# Get statistics on petal length (3rd column)
$ cut -d "," -f 3 iris.csv | stats --skip-header

  Mean:     3.758
  Variance: 3.0955 (1.7594 SD)
  Min:      1
  Max:      6.9
  Count:    150
  Q1:       1.6
  Median:   4.4
  Q3:       5.1

Options

• -j, --json: Output the statistics in JSON format if you want to use them in a subsequent program
• -q, --quartiles: Compute the median, Q1 and Q3 quartiles. (This is not enabled by default because computing these values implies storing all values in memory which can be a problem with very large inputs)
• -s, --skip-header: Ignores the first line of the input. (Useful when parsing from csv files with headers)
• -h, --help: Show help message