Happenings – 2012 Sep 8

The only math I’ve done this week has been linear programming. It will be worthwhile to put out a second post using a minimization problem instead of a maximum. That is, I discovered I had questions about sensitivity analysis after I finished the minimum problem.

Sensitivity analysis? That’s the part where I said that x2 would enter the optimal solution if its profit rose by 42 cents… and the part where I said the shadow prices on the slack variables told me what I should be willing to pay for more of the resources which I had completely used up.

What happens when it’s a minimization problem instead? I know what I expect… but I haven’t verified the answers.

In addition, I am making progress on understanding the transformation of the cost (or profit) vector from initial conditions to final tableau.

And that’s it for math.

With Federer out of the US Open, I will probably be rooting for Murray. But maybe I should do math instead.

Finally, it turns out that function-shift-return acts as shift-enter on the new Apple keyboards. Well, I like the extended keyboard, so I don’t regret buying it – but now I could also use the default keyboard. What I do regret buying is the separate keypad that the Apple Store guy suggested. My bad… I paid the price (pun intended).

OK, let me get rolling today.