diff options
| -rwxr-xr-x | leapsecond.py | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/leapsecond.py b/leapsecond.py index 977b1b19..dab5ca40 100755 --- a/leapsecond.py +++ b/leapsecond.py @@ -167,9 +167,17 @@ def graph_history(filename): "Generate a GNUPLOT plot of the leap-second history." raw = fetch_leapsecs(filename) (b, c) = leastsquares(zip(range(len(raw)), raw)) + maxerr = 0 + for (i, r) in enumerate(raw): + err = r - (i * b + c) + if err > maxerr: + maxerr = err + maxerr /= (60 * 60 * 24 * 7) dates = map(lambda t: time.strftime("%Y-%m-%d",time.localtime(t)), raw) fmt = '' + fmt += '# Least-squares approximation of Unix time from leapsecond is:\n' fmt += 'lsq(x) = %s * x + %s\n' % (b, c) + fmt += '# Maximum residual error is %.2f weeks\n' % maxerr fmt += 'set autoscale\n' fmt += 'set xlabel "Leap second offset"\n' fmt += 'set xrange [0:%d]\n' % (len(dates)-1) |