import argparse

import csv

import math

import statistics

parser = argparse.ArgumentParser()

parser.add_argument('-d', '--discard', type=int, default=0, help='Number of initial measurements to discard')

parser.add_argument('-i', '--input', required=True, help='Input CSV file')

parser.add_argument('-o', '--output', required=True, help='Output CSV file')

args = parser.parse_args()

time_dict = dict({})

count_dict = dict({})

with open(args.input) as csv_file:

csv_reader = csv.reader(csv_file)

next(csv_reader)

for row in csv_reader:

name = row[2]

time = float(row[3])

count = row[1]

if name in time_dict.keys():

time_dict[name].append(time)

else:

time_dict[name] = [time]

count_dict[name] = 1 if count == '' else int(count)

data = [["name", "mean", "stdev", "count"]]

for name, time_list in time_dict.items():

count = count_dict[name]

mean = statistics.mean(time_list[args.discard:]) / count

runs = len(time_list[args.discard:])

stdev = 0.0 if runs == 1 else statistics.stdev(time_list[args.discard:]) / math.sqrt(count)

data.append([name, mean, stdev, runs * count])

with open(args.output, 'w') as csv_file:

csv_writer = csv.writer(csv_file)

csv_writer.writerows(data)