Log

[fponticelli]

I added the log function to the set of math functions. It seems to work fine in some cases (egg below) and fail on other (glass). I am not sure my change introduced those errors or how to protect from them.

(define (glass)
(lambda-shape (x y z)
  (+ (* x x) (* y y) (* (log (+ z 3.2)) (log (+ z 3.2))) 0.02))
)


(define (egg)
(lambda-shape (x y z)
  (+ (* x x) (* y y) (* (log (+ z 3.2)) z) 0.02))
)

[mkeeter]

Thanks, I'll check this out and see why glass isn't working.

[mkeeter]

Are you sure that you're using the chain rule correctly for the derivatives?

For example, in the derivative evaluator, you're saying

od = ad * log(av);

but checking with Wolfram Alpha shows

[mkeeter]

Yup, the derivatives are noticeably wrong. Look at the bottom of the egg here:

vs with fixed derivatives:

I fixed the derivatives, rebased, and merged this in e6d8c67

(glass is still crashing, but that's a kernel bug and I'll open up another issue for that)

[fponticelli]

That's great, thank you!