Joining together ordered sample points (xi, yi) when ths xi's are different yields a piecewise linear continuous (P1) function. This snippet defines a handy class to manipulate these functions. It allows
computing the value and the slope of the function at each point, arithmetic operations, absolute value, truncation and linear combinations of such functions, maximum, minimum and integral between bounds. If wxPython is installed on your system, the class also allows plotting the function in a wx plot widget.