Are you a fan of cricket? Then you must have observed those worm graphs depicting the pace at which the two teams were playing in a match at a particular instance of time. Here’s an example of a worm graph, depicting the iconic World Cup 2011 final.
This graph is an example of a line graph (when drawn at such a scale it resembles a “crawling worm”). In the earlier session on matplotlib, you learnt what is a line graph and its main uses. Its main feature is that it utilises continuous time-dependent data to accurately depict the trend of a variable. In the next video, let’s see how you can build a line chart for the case study.
[Note: Earlier you used the parse_time parameter to index the date-time fields. In this demo, you’ll be using another pandas function pd.to_datetime. You’re advised to check its documentation before watching this video.]
Here are the steps you followed to create the line chart:
- You converted the date column to a date_time object using pd.to_datetime.
- After that, you found the average rating for each month using a groupby.
- Then, you used the plot function of matplotlib to create a line chart. The following is the line chart obtained:
Though not quite significant, there is indeed some improvement in the ratings during the months of July-August. Note that, here, we have assumed the Last Updated month to be the one in which all the reviews and ratings are coming from the users.
Additional Notes
- Line charts are more or less utilised only for time-series data. Therefore, you’ll be using them predominantly while working on forecasting and other time series models.