Matplotlib Legend and Color Key - Time Series Mechanics

Read the Key First

Start with two channels, Email and Chat, each shown twice. The legend says blue means this week and gray means last week. So compare blue with blue when reading this week: Email is 8 and Chat is 5. Email is 3 more than Chat this week.

A tiny chart-reading step: read the legend before comparing colored marks.

highlighted = computed this step

Start with colored-series data

Start with 4 pinned colored marks.

\text{pinned colored marks}

Read the legend first

Read the legend before comparing: blue means this week and gray means last week.

\text{legend first}

Match colors to values

Use the legend to match each colored bar to the right series.

\text{match color to series}

Compare after the key

Readout: for blue bars, Email is 3 more than Chat this week.

\text{compare after key}