On Tue, Oct 1, 2019 at 8:58 PM David Christensen <dpchr...@holgerdanske.com> wrote:
> On 10/1/19 8:32 PM, Dan Hitt wrote: > > I'm half-way looking for some shell wrappers for common trig functions > like > > sin, cos, exp, log, and others. > > > > I'm aware of bc, but it seems cumbersome. > > > > I would like to just type 'sin 1' and get the sine (of 1 radian), > > Perl one-liners are an option: > > 2019-10-01 19:25:59 dpchrist@tinkywinky ~ > $ perl -e 'print sin 1' > 0.841470984807897 > > > > or type 'log 2' > > 2019-10-01 20:48:52 dpchrist@tinkywinky ~ > $ perl -e 'print log 2' > 0.693147180559945 > > > > and get the natural or maybe common log of 2. (Probably any such > > program should do something intelligent when faced with multiple or zero > > arguments, such as computing the sine or log of each, so that they could > be > > chained together. And maybe such a program would pay attention to > > environment variables or optional command line arguments to tune its > > behavior.) > > > > These kinds of programs would be super-easy to write in just about any > > language (i guess perhaps even just as bash functions which shell out to > bc > > for at least some of the simpler functions) but before i actually do > > something like that, i wonder if somebody has already done it, whether > > there exist any standards or good ideas, etc. (Because if somebody has a > > good, thoughtful exp program, for example, then it could be cookie-cutter > > copied to a bunch of other functions.) > > > > There is a precedent of sorts in Paul Rubin's factor program, which is > just > > oh-so-handy when you're wondering how an integer factors, but don't want > to > > start up some heavy-weight system just to find out. > > 2019-10-01 20:49:17 dpchrist@tinkywinky ~ > $ apt-cache search libmath-prime-util-perl > libmath-prime-util-perl - utilities related to prime numbers, including > fast sieves and factoring > > > > Thanks in advance for any pointers or advice! :) > > > > dan > > > David > > Hi David, Thanks so much for your reply, including the apt-cache searching part. It does look like a way to quickly get values for sine (or any other function in perl). However, i would like to dispense entirely with the 'perl -e' and 'print' part. I really would like stand-alone programs. This would absolutely minimize any typing, and if the programs had a set of good conventions, then they would provide a model for writing others if the functions i want are not already available in perl (or other interpreter). Thanks again for the suggestion and example!! :) dan
