Re: How do you write tests if you aren't sure what the result should be?

Hi Avi …

On Feb 16, 2013, at 2:47 PM, Avi Kessner <[email protected]> wrote:

> The basic formula for the penguin flying through the air is  x += dt + v
> If this is calculated 30 times per second you basically get x += dt +
> 30v,   but if you calculate it  32 times per second, you get  x +=
> (dt*0.937) + 32v


That formula (x += dt + v) doesn't seem right to me.

if velocity is v meters per second, then the distance travelled in time interval dt is v*dt, isn't it?

so I'd expect x += v*dt always.

I don't see what this dt + v is about, much less the (dt*0.937) + v. I get that 30/32 is 0.9375, but I expect to see that multiplied by velocity not added.

Can you explain to me what's going on?

Ron Jeffries
www.XProgramming.com
I'm not bad, I'm just drawn that way.  -- Jessica Rabbit



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