Known plots: X=966 Y=8.54 X=1299 Y=7.87 I need an equation where I enter X each time to figure Y Tks Too many decades since I did this Real world need, not hypothetical

Assuming a linear fit, 2 points only: slope m = (y1 - y2)/(x1 - x2) m = (8.54 - 7.87)/(966 - 1299) = -2.01e-3 y = mx + b => b = y - mx choose any point: b = 8.54 - (-2.01e-3 * 966) = 10.5 so y = -2.01e-3 x + 10.5 I've kept each of the calculated values to 3 sigdigs.

the volume of a thick crust pizza with height "a" and radius "z" is π·(radius)2·(height), or pi*z*z*a. also, I had pizza for dinner.

-0.00201 And I should have written: y = -2.01e-3x + 10.5 I forgot the x when I orignally posted. It's corrected now Sent from my iPhone using Tapatalk Pro

Try using quaternions instead. Less processing, and you’ll avoid gimbal lock. Half-Fast, Retired servo geek

I learned it as, “Two points define a line and three points don’t. Three points define a plane and four points don’t.”

FlyBy E6B (if you have an iPhone or iPad) has an interpolation function that you may want: http://www.skywritersoft.com/ios/flybye6b/flybye6biphone.html Also available on Android: https://play.google.com/store/apps/details?id=skywritersoft.com.flybye6b&hl=en_US&gl=US

Bought my HP-15C shortly after college graduation. It carried me through 36 years of engineering practice at Lockheed and it’s still going strong now that I’m doing pro bono stuff. They don’t build ‘em like that anymore and that’s a real shame.

Oh FFS...(corrections in red) [966 1;1299 1]\[8.54;7.87] Code: [966 1;1299 1]\[8.54;7.87] ans = -0.0020 10.4836 >> Nauga, who is better with Matlab than typing

OP, e-3 means "times 10 to the -3 power", i.e. move the decimal point three places left. It became common with computers, which don't handle superscripts. IIRC, I first encountered this when using Lotus 1-2-3 in the 1980s. Here is a Wiki page which addresses this; look about 1/3 the way down: https://en.wikipedia.org/wiki/Scientific_notation