TableOfReal: Draw biplot...

A command to draw a biplot for each column in the selected TableOfReal object.

Settings

Xmin, Xmax, Ymin, Ymax
determine the drawing boundaries.
Split factor
determines the weighing of the row and column structure (see below).

Behaviour

1. Get the singular value decomposition U Σ V′ of the table.
2. Calculate weighing factors λ for row and columns
λr,1 = σ1splitFactor
λc,1 = σ11-splitFactor
λr,2 = σ2splitFactor
λc,2 = σ21-splitFactor
where σ1 and σ2 are the first and the second singular values
3. For the rows (i from 1..numberOfRows) form:
xri = Ui1 λr,1
yri = Ui2 λr,2
4. For the columns (i from 1..numberOfColumns) form:
xci = Vi1 λc,1
yci = Vi2 λc,2
5. Plot the points (xri, yri) and (xci, yci) in the same figure with the corresponding row and column labels.

© djmw, June 3, 2002