Transactions of the American Mathematical Society, Vol. 176 (Feb., 1973), pp. 305-318 (14 pages) The theory of monotone matrix functions has been developed by K. Loewner; he first gives some necessary ...

Annals of Mathematics, Second Series, Vol. 176, No. 3 (November, 2012), pp. 1783-1826 (44 pages) We prove generalizations of Löwner's results on matrix monotone functions to several variables. We give ...

Functions of two variables can be visualized in many ways: heat maps in 2D, contour curves in 2D, wireframes in 3D, surfaces in 3D. We begin by defining a function of two variables, building an array ...

Explore how covariance reveals relationships between variables, its role in financial planning, and its application in the stock market for better investment strategies.