|Re: HP71B Maths Module|
Message #11 Posted by Valentin Albillo on 3 May 2012, 7:33 a.m.,
in response to message #10 by John Abbott (S. Africa)
Thanks Valentin, I have previously read all your articles and find them, and your previous challenges fascinating. Yes I am into Math, Engineering, Stats and physics and while the HP71 is a great machine, the Math Rom is a must as I see it. So I will keep looking.
Thanks to you for your kind words and interest in my humble HP-related productions and I wish you the best of lucks in getting the Math ROM. When you eventually do, which I'm sure you will, you can try it with the following textbook-like problem, which is solved quickly and effortlessly:
"The region R between the spheres of radius 4 and 5 is filled with a material whose density is given by D(x,y,z)=1+x2+y2.
Find the mass of this region."
My quick-'n'-dirty 4-line HP-71B + Math ROM solution is:
10 DEF FNF(Z,F,R)=(1+(R*SIN(F))^2)*R*R*SIN(F)
20 DEF FNG(X,Y)=INTEGRAL(4,5,P,FNF(X,Y,IVAR))
30 DEF FNH(X)=INTEGRAL(0,PI,P,FNG(X,IVAR))
40 RADIANS @ P=1E-7 @ DISP INTEGRAL(0,2*PI,P,FNH(IVAR))
>CALL IDENTIFY(IVALUE,S$) @ S$
where IDENTIFY is the parameterless invocation of my constant recognition subprogram as featured in one of my articles, namely Boldly Going - Identifying Constants downloadable from the link I previously gave.
So, as you can see, a complicated triple-integral problem is numerically solved in just 4 lines of simple Math ROM code, plus full symbolic recognition available as well if needed. What more can one ask for ? ... :D
Regards from V.