highs_lows.py

# Author: Bojan G. Kalicanin
# Date: 26-Dec-2016
# Analysis of high and low temperatures.

import csv
from matplotlib import pyplot as plt
from datetime import datetime

# Get dates, high, and low temperatures from file.
fig = plt.figure(dpi=100, figsize=(10, 9))
filenames = ['sitka_weather_2014.csv', 'death_valley_2014.csv']
for filename in filenames:
    #filename = 'death_valley_2014.csv'
    with open(filename) as f:
        reader = csv.reader(f)
        header_row = next(reader)
        
        dates, highs, lows = [], [], []
        for row in reader:
            try:
                current_date = datetime.strptime(row[0], '%Y-%m-%d')
                high = int(row[1])
                low = int(row[3])
            except ValueError:
                print(current_date, 'missing_data')
            else:
                dates.append(current_date)
                highs.append(high)
                lows.append(low)

    # Plot data.
    
    plt.plot(dates, highs, c='red', alpha=0.5)
    plt.plot(dates, lows, c='blue', alpha=0.5)
    plt.fill_between(dates, highs, lows, facecolor='blue', alpha=0.1)


# Format plot.
title = "Daily high and low temperatures - 2014\nDeath Valley, CA"
plt.title(title, fontsize=24)
plt.xlabel('', fontsize=16)
fig.autofmt_xdate()
plt.ylabel("Temperature (F)", fontsize=16)
plt.tick_params(axis='both', which='major', labelsize=16)
plt.axis([None, None, 15, 120])

plt.show()