Monthly Archives: September 2007

Rob explains Calculus

If you’re one of the 60% of the population that never took Calculus, but want to find out what it’s all about, check out my friend Rob’s Calculus Tutorial. His goal is to make it understandable in a short period of time for a layperson, and he would really appreciate your feedback if you can’t quite get it after reading.

Fixing Figures with OmniGraffle

Sometimes, someone sends you a figure or image of some kind that you need, but it doesn’t look good — the resolution is too low, the background was trimmed off poorly, whatever. You could ask them to fix it, but often they won’t know how, or it won’t be possible to obtain a higher-resolution version.

When this happens to me, I use OminiGraffle to fix it. OmniGraffle is the main thing that keeps me from going back to using only Linux. There’s nothing remotely comparable to OmniGraffle in either the Windows or Linux worlds. Now that I’ve gushed about it, here’s the general approach to fixing a figure with OmniGraffle (or an inferior vector illustration program).

  1. Load the original figure and lock it down, so that you can use it as an alignment and placement guide and draw on top of it.
  2. Load the original figure in an image editor and cut out anything useful, pasting it in over the background into the vector editor right where it was before.
  3. Draw in the rest of the figure. Often this includes coordinate axes, numbers, labels, whatever.
  4. Hide or delete the background layer and export your new, clean figure.

I also like to do fun things like snipping out sequential images and animating them to make a movie for presentations (with citations of course), but that requires different tools.

Survival Exercise

I’ve never been any good at sports involving flying objects. I used to think that meant I would never enjoy anything athletic. Of course, I was in pretty bad shape at the time, which didn’t help.

Now I’m in much better shape. I still can barely throw a football or a baseball with any distance or accuracy, but I’m passable at a few things, namely swimming, running, bicycling, and rock climbing (of the indoor variety). It occurred to me at some point that these are useful athletic activities to practice both for literal survival, and for accomplishing various tasks that are not life-threatening. For example:

  • Swimming: Life or Death – Falling out of a boat that’s moving fast enough that you can’t just get right back in. Other tasks – You dropped something really important off a dock and it’s not pointless to get it back (i.e. in the case of a cell phone).
  • Running: Life or Death – Someone is trying to kill you, or a velociraptor is after you. Other tasks – Your first of two flights was running late. The second is on the other side of the airport and will leave in 5 minutes. Go!
  • Bicycling: Life or Death – OK, can’t think of anything for this one. Other tasks – Making groceries, commuting, etc.
  • Rock Climbing: Life or Death – You were working on the roof and lost your footing. You manage to catch yourself on the edge of the roof / gutter. Other tasks – anything on a ladder in an awkward position. I used climbing techniques setting up for our wedding reception, and was a lot more comfortable on a ladder than I had been before starting rock climbing.

I suppose throwing things (i.e. spears) could be important to post-apocalyptic survival. In that case, I’m screwed.