#!/usr/bin/env bash

#

# Computes a commit interval histogram.

#

# References:

#

# * Kolassa, Carsten, Dirk Riehle, and Michel A. Salim. 2013. "The Empirical Commit Frequency Distribution of Open Source Projects." In *Proceedings of the 9th International Symposium on Open Collaboration*, 18:1–:8. WikiSym '13. New York, NY, USA: ACM. doi:[10.1145/2491055.2491073](http://dx.doi.org/10.1145/2491055.2491073).

# Determine root directory:

root="$(git rev-parse --show-toplevel)"

# Define the path to a utility to compute commit intervals:

commit_intervals="${root}/tools/git/scripts/commit_intervals"

# * `commit_intervals`

# - Get commit intervals (in seconds).

# * `awk '{}'`

# - Generate histogram.

# * `sort -n`

# - Sort in numeric order.

"${commit_intervals}" | awk '

BEGIN {

hr = 60 * 60

}

{

# Round interval to nearest hour:

bin = int($0/hr + 0.5)

hist[bin] += 1

}

END {

for (bin in hist) {

print bin OFS hist[bin]

}

}

' | sort -n