Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. In mathematics, and particularly ordinary differential equations, a monodromy matrix is the inverse of the fundamental matrix of a system of ODEs evaluated at zero times the fundamental matrix evaluated at the period of the coefficients of the system. In mathematics, an ordinary differential equation (or ODE) is a relation that contains functions of only one independent variable, and one or more of its derivatives with respect to that variable.