Git time histogram

git-hours.sh

git log --date=format:%H --pretty=format:%ad | \
awk '
{ h = int($0); cnt[h]++; total++ }      # collect counts & grand total
END {
  # find max bucket to rescale bars
  for (i = 0; i < 24; i++) if (cnt[i] > max) max = cnt[i]

  barWidth = 50                         # chars for the widest bar
  for (i = 0; i < 24; i++) {
    ampm = (i < 12) ? "AM" : "PM"
    hr   = (i % 12 == 0) ? 12 : i % 12
    pct  = (total ? cnt[i] * 100 / total : 0)
    len  = (max   ? int(cnt[i] * barWidth / max) : 0)

    printf "%2d%s | %6d | %5.1f%% | ", hr, ampm, cnt[i], pct
    for (j = 0; j < len; j++) printf "█"
    print ""
  }
}'