This visualization shows the correlation matrix for physical measurements of abalones, comparing length, diameter, height, various weights, and rings (age). Each cell is colored according to the strength of correlation, revealing strong relationships among size and weight variables and weaker correlations with age. The code uses D3 v4’s scale functions and SVG rendering to draw a grid of colored rectangles. Precomputed correlation values for both female and male abalones are embedded as data arrays, with axis labels placed along the top and left edges for each variable.