plot bin2d

Creates a 2D binning heatmap (density plot) of two numeric columns.

Behavior:

• Divides the plane into rectangular bins and counts the number of points in each bin.
• Visualizes the density using character intensity in the terminal.
• Supports automatic bin count strategies or custom bin counts/widths.
• Density scale (low to high):
  • · ≥5% (dark grey)
  • ░ ≥20% (grey)
  • ▒ ≥40% (white)
  • ▓ ≥60% (yellow)
  • █ ≥80% (red)
• Values below 5% are not shown.

Input:

• Reads from files or standard input.
• Files ending in .gz are transparently decompressed.
• Assumes the first line is a header row with column names.

Output:

• Renders a heatmap to the terminal using character density.

Examples:

1. Basic 2D binning tva plot bin2d data.tsv -x age -y income

2. Specify number of bins tva plot bin2d data.tsv -x age -y income --bins 20

3. Different bins for x and y tva plot bin2d data.tsv -x age -y income --bins 30,10

4. Use automatic bin count strategy tva plot bin2d data.tsv -x age -y income -S freedman-diaconis

5. Specify bin width tva plot bin2d data.tsv -x age -y income --binwidth 5

6. Custom chart size tva plot bin2d data.tsv -x age -y income --cols 100 --rows 30