# Who needs math? Funny you should ask…

Remember that guy in the tenth grade who would torment your math teacher by asking, “When are we ever going to use this crap?” Or perhaps you grew up in a nicer neighborhood where that guy said, “When are we ever going to use this stuff?”

I’m here to tell you, ladies and gentlemen, that I am USING THAT STUFF. I have just USED IT. I have braided that math into a nice little charm bracelet for my wrist.

To whit, check it. What you are about to see has just made my brain hurt so bad that I think I need a lie-down. Which is fitting, since it’s midnight.

What the WHAT?, I can hear you thinking. What on earth is that? That, friends, is the set of calculations — that I programmed into Excel — required to figure out a set-in sleeve on a sweater. There are simpler sleeves that have squarer shapes (read: easier math), but this curvier sleeve fits the human body better.

To determine the shape of that sleeve, you have to use:

• the Pythagorean theorem
• parentheses to signal to Excel which operations get done first
• the vague memory that any number to the 1/2 power is the same thing as the square root of that number (I was super-dee-duper impressed with myself for remembering that one)
• and other whatnot

The numbers all look consistent with each other, so now I just have to check that they will fit an actual human body. That’s where the physics comes in — that is, the knitting.

If you’re thinking I’m pretty awesome right now — and I feel certain that you are — then let me give credit where credit is due. I’ve been learning how to calculate sleeve caps from a wonderful online class with Knitgrrl Studios. And I have learned a tremendous amount about how to make Excel do some of the work for you from the stupendously generous Marnie Maclean. Really, that woman deserves a medal.

## One thought on “Who needs math? Funny you should ask…”

1. There was a small explosion. I’m now holding my head together with duct tape…..