pulsgraph.py

#!/usr/bin/python3
import matplotlib.pyplot as plt
from datetime import datetime, timedelta
import numpy, csv, sys
from itertools import groupby
from functools import partial

reader = csv.reader(open("data.csv", "r"), delimiter=";")
next(reader, None) # skip header

data = numpy.array([
    (datetime.strptime(datestr, "%Y-%m-%d %H:%M:%S"), int(valstr))
        for [datestr, valstr, *_] in reader])

def bymin(mins, d): 
    date,val = d
    return date - timedelta(minutes=date.minute%mins,seconds=date.second)

def average(averager, vals):
    return averager([v for (k,v) in vals])

def make(name, grouper, averager):
    grouped = numpy.array([(date, average(averager, vals)) for (date, vals) in groupby(data, grouper)])
    plt.figure(figsize=(20,10))
    dp = plt.plot([date for date,val in grouped], [val for date,val in grouped])
    plt.savefig(name+".png")

make("mean5",   grouper=partial(bymin, 5), averager=numpy.mean)
make("mean1",   grouper=partial(bymin, 1), averager=numpy.mean)
make("median5", grouper=partial(bymin, 5), averager=numpy.median)
make("median1", grouper=partial(bymin, 1), averager=numpy.median)