mathematical-optimization

Stack Overflow has this question answered in many other languages, but not C. So I thought I'd ask, since I have the same issue. How does one concatenate two integers in C? Example: x = 11; y = 11; I would like z as follows: z = 1111; Other examples attempt to do this with strings. What is a way to do this without strings? I'm looking for an efficient way to do this in C because in my particular usage, this is going into a time critical part of code. Thanks in Advance! Mooing Duck unsigned concatenate(unsigned x, unsigned y) { unsigned pow = 10; while(y >= pow) pow *= 10; return x * pow + y; }

I use scipy.optimize to minimize a function of 12 arguments. I started the optimization a while ago and still waiting for results. Is there a way to force scipy.optimize to display its progress (like how much is already done, what are the current best point)? As mg007 suggested, some of the scipy.optimize routines allow for a callback function (unfortunately leastsq does not permit this at the moment). Below is an example using the "fmin_bfgs" routine where I use a callback function to display the current value of the arguments and the value of the objective function at each iteration. import

I am using CPLEX for solving huge optimization models (more than 100k variables) now I'd like to see if I can find an open source alternative, I solve mixed integer problems (MILP) and CPLEX works great but it is very expensive if we want to scale so I really need to find an alternative or start writing our own ad-hoc optimization library (which will be painful) Any suggestion/insight would be much appreciated I personally found GLPK better (i.e. faster) than LP_SOLVE. It supports various file formats, and a further advantage is its library interface, which allows smooth integration with your