I wrote a small python2 application to keep track of a watch/clock's daily rate error. It's a console-only mimic of an Android app that I use on my phone to track my watch timekeeping.

I wrote it mainly as a thought-experiment rather than as a fully functional piece of code.

You put the application in a directory specific to the watch and execute it from that directory. the data from each measurement is stored in a json file in the same directory.

#! /usr/bin/env python
 
## a text-terminal version of the WatchCheck app
## to track error, daily error rate of timepieces.
# auto update?
#
import time
import datetime
import json
 
 
 
 
def write_file(text):
    filename = "logfile.txt"
    f = open(filename, 'a+')
    timenow = time.strftime("%d/%m/%Y %H:%M:%S", time.gmtime(time.time()))
    log = " ".join((timenow, text, "\r\n"))
    f.write(log)
    f.close()
 
 
 
 
def get_delta():
 
    print time.strftime("Current Time = %H:%M")
 
    h = time.strftime("%H")
    w = raw_input("Watch time %s:" % (h))
    print w
 
    date = time.strftime("%Y/%m/%d")
    s = date + " " + h +":"+ w +":00"
 
    raw_input("Press enter when seconds = 0 ")
 
    watchtime = time.mktime(datetime.datetime.strptime(s, "%Y/%m/%d %H:%M:%S").timetuple())
    record_time = time.strftime("%Y/%m/%d %H:%M:%S")
    timenow = time.time()
    delta = watchtime - timenow
 
    return record_time,delta
 
 
def watch_stat():
 
    try:
        saved_error = open('error_list.json')
        error_list = json.load(saved_error)
    except:
        error_list = []
 
    if len(error_list) > 1:
        first_record = error_list[0]
        latest_record = error_list[-1]
        previous_record = error_list[-2]
 
        first_time = first_record[0]
 
        first_delta = first_record[1]
 
        latest_time = latest_record[0] 
        latest_delta = latest_record[1]
 
        previous_time = previous_record[0]
        previous_delta = previous_record[1]
 
        FMT = '%Y/%m/%d %H:%M:%S'
 
        t_latest = datetime.datetime.strptime(latest_time, FMT)
        t_previous = datetime.datetime.strptime(previous_time, FMT)
        t_first = datetime.datetime.strptime(first_time, FMT)
 
        tdelta = t_latest - t_previous
        full_delta = t_latest - t_first
 
        elapsed_time = tdelta.total_seconds()
 
        full_time = full_delta.total_seconds()
 
        print "First record time ", first_time
        print "First record delta ", first_delta
        print ""
 
        print "Previous record time ", previous_time
        print "Previous record delta ", previous_delta
        print ""
 
        print "Latest record time " , latest_time
        print "Latest record delta ", latest_delta
        print ""
 
        print "Overall elapsed time ", full_delta
        print "Latest elapsed time ", tdelta
        print ""
 
        # Current Error rate
        time_error = latest_delta - previous_delta
        error_rate = time_error / elapsed_time
        daily_rate = error_rate * (60*60*24)
        ppm_daily = error_rate * 1000000
 
        # Overall Error rate
        total_error = latest_delta - first_delta
        average_error_rate = total_error / full_time
 
        average_rate = average_error_rate * (60*60*24)
        ppm_overall = average_error_rate * 1000000
 
 
        print "Latest delta change ", time_error
 
        print "Latest elapsed time %d seconds " % (elapsed_time)
 
        print ""
        print "Daily PPM : %0.3f" % ppm_daily
        print "Daily rate error: %0.1f s/d " % (daily_rate)
 
        print ""
        print "Total Time %d seconds" % (full_time)
        print "Total error ", total_error
        print "Total PPM : %0.3f" % ppm_overall
        print "Total rate error: %0.1f s/d" % (average_rate)
        print ""
        print "========================================================"
        print " Delta : %+0.1f s | Rate : %+0.1f s/d | Average : %+0.1f s/d" % (latest_delta, daily_rate, average_rate)
        print "========================================================"
        print ""
        text = "\t%+0.1f\t\t%+0.1f\t\t%+0.1f" % (latest_delta, daily_rate, average_rate)
        write_file(text)
    else:
        print "No rate yet"
 
 
def new_record():
 
    try:
        saved_error = open('error_list.json')
        error_list = json.load(saved_error)
    except:
        error_list = []
 
    s,delta = get_delta()
 
    print ""
    print "%s \n\nDelta %0.1f seconds" % (s, delta)
    last_data=[s,delta]
    error_list.append(last_data)
    #print error_list
 
    with open('error_list.json', 'wb') as outfile:
        json.dump(error_list, outfile)
 
    return
 
def delete_last():
    try:
        saved_error = open('error_list.json')
        error_list = json.load(saved_error)
    except:
        error_list = []
    error_list.pop()
 
    with open('error_list.json', 'wb') as outfile:
        json.dump(error_list, outfile)
 
    return
 
 
def menu():
    print "Wire2waves WatchCheck....."
    print "=========================\n"
    print "N : New Record\nD : Delete Last\nS : Stats\nQ : Quit\n"
    choice = raw_input("Command > : ").upper()
    if choice == "N":
        print "New"
        new_record()
        watch_stat()
        menu()
    elif choice == "S":
        print "Stat"
        watch_stat()
        menu()
    elif choice == "D":
        delete_last()
        watch_stat()
        menu()
    elif choice == "Q":
        return
    else:
        print "?"
        menu()
 
 
menu()

Running it for the first time, with no previous records stored, looks like this:

Wire2waves WatchCheck.....
=========================

N : New Record
D : Delete Last
S : Stats
Q : Quit

Command > : n
New
Current Time = 10:18
Watch time 10:19
19
Press enter when seconds = 0

2022/05/04 10:19:30

Delta -30.2 seconds

and the first time-delta is stored in the error_list.json file like this:

[["2022/05/04 10:19:30", -30.179980039596558]]

I'll update this once I've done a second measurement, in a day or so….

John Pumford-Green Wed May 4 09:09:09 2022

Page Updated : 06/03/25 06:49 GMT