This Matplotlib Scatter lesson is for a beginner. Read the short notes, run each example, then change one name or number and run it again.
A scatter plot draws a point for each pair and does not connect them. Use it when the order of rows is not a line.
Each pair below is one dot.
Example 1: Start here
plt.scatter(hours, scores) draws those dots.
hours = [1, 2, 4, 5] # a list; the values stay in this order
scores = [60, 70, 85, 88] # a list; the values stay in this order
print(list(zip(hours, scores))) # zip keeps each pair together
Example 2: List the points
Matplotlib Scatter draws points. Printing each pair lets you check the data before a chart library plots it.
points = [(1, 9), (2, 12), (3, 18)] # a list; the values stay in this order
for x, y in points: # repeat the indented lines once per value
print(x, y) # a comma prints each value, with a space between
Example 3: Find the highest bar
The tallest bar is the largest number. max does that lookup.
heights = [9, 12, 18] # a list; the values stay in this order
print(max(heights)) # the largest value
Example 4: Label each point
A chart label belongs with its number. zip keeps each day next to its height.
labels = ["Mon", "Tue", "Wed"] # a list; the values stay in this order
heights = [9, 12, 18] # a list; the values stay in this order
for label, height in zip(labels, heights): # repeat the indented lines once per value
print(label, height) # a comma prints each value, with a space between
plt.scatter(hours, scores) draws those dots.
