I have been playing around with d. (derivative) and noticed a few places where J does not supply straightforward derivatives and integrals.
The most obvious omissions are derivatives and integrals of inverse trigonometric and inverse hyperbolic functions. These get used a fair amount and would be handy to have. I also don't see why 0&o., 4&o., 8&o. and their inverses should be not differentiable: J can do them if they are spelled out. Similarly, j. is differentiable and integrable, but its alias _11&o. is not. I am not suggesting that J aim for the type of symbolic calculations done by Maple or Mathematica, and I know how to use u`v D. n to supply a derivative: it would just be nice to have the obvious gaps filled in. Best wishes, John ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
