A matrix is a two-dimensional grid of numbers. The dimensions are expressed as the number of rows and columns in the matrix.
For example, A is a matrix with four rows and two columns:
In mathematical notation, a matrix will usually be assigned to a variable with an upper-case letter to distinguish it from other variables in an equation.
We can construct a matrix from our dataset using Incanter's
(defn ex-3-16  (->> (swimmer-data) (i/$ ["Height, cm" "Weight"]) (i/to-matrix)))
Incanter also defines the
incanter.core/matrix function that will take a sequence of scalar values or a sequence of sequences and convert ...