February 21 2007
derio 40
My goal is to obtain a formula F:= x -> fa(x)*c1_1(x)+ fb(x)*c1_2(x)+fc(x)*c2_1(x)+... where every ci_j(x) is a function of x. fa, fb, fc are known functions of x. I do not need to have it printed, I just need it to return a numerical value for every value of x I throw in.
I have obtained the solutions of ci_j's in the form
Sol[1]:=[c1_1=f11(x), c1_2=f12(x), c1_3=f13(x), ...], N1 terms
Sol[2]:=[c2_1=f21(x,c1_j’), c2_2=f22(x,c1_j’), c2_3=f23(x,c1_j’), ...], N2 terms
Sol[3]:=[c3_1=f31(x,c1_j’,c2_j’), c3_2=f32(x,c1_j’,c2_j’), c3_3=f33(x,c1_j’,c2_j’), ...], N3 terms
Sol[4]:=[c4_1=f41(x,c1_j’,c2_j’,c3_j’), c4_2=f42(x,c1_j’,c2_j’,c3_j’), c4_3=f43(x,c1_j’,c2_j’,c3_j’), ...], N4 terms

The Cartesian product of a sequence of *m* lists
L_{1}, ..., L_{n},
with list *i* having *n*_{i} elements,
is given by the sequence of Π_{i} *n*_{i} lists
[L_{11},...,L_{m1}], ...,
[L_{1n1},...,L_{mnm}],
where L_{jk} is the *k*-th element of the *j*-th list.

How can I convert an expression into a function? For example, let's in the course of some calculations I get the output: x + sin(x)
How can I convert this into f:=x->x+sin(x) without really spelling it out? Thanks in advance.

Sorry for the repetition. I posted this last night as a reply rather than a new posting.
I am having difficulty converting latex files with maple-graded questions. It appears that it does not recognize the question type even though the documentation claims that all question types are available with latex.
If I try this example or any of the examples in the latex authoring documentation, it generates errors on the latex2edu conversion site.
```
\documentclass[12pt]{article}
\usepackage{ed}
\setImageBase{../classes/myclass/images}
\begin{document}
\begin{topic}{fun}
\begin{question}{Maple}
```

Using with(Units)
If I enter something like:
P := 1 [[atm]]
And then right click to convert this to torr, it does so like this:
P := 1 [[atm]] -> 760 [[torr]]
But then, if I check the value of P, it is still given in [[atm]]. How can I make the new units append to the previous value?
In general, I'm having a difficult time working with units in Maple. Any suggestions?

Hi
Short question version:
ss := ["abcd", " efg", " hijk", " lm_r", " stuv_k"]
How can this be converted to:
ss := [abcd, efg, hijk, lm_r, stuv_k]
(ie just remove the quotation marks.)
Thanks
David
Longer version:
This was meant to be a reply to a previous question posted about 2 days ago, but I have failed to find it. (Sadly I have failed in my attempt to answer his question anyway.) No doubt my lack of being able to successfully use the sort features - are they working properly? (They just seemed to be in a different random order?)
restart:
ss:="abcd # efg # hijk, lm_r, stuv_k":

I'm having a problem to convert my answer to radical term. I've use 'convert' command' but Maple doesn't work.
Thank you for your help.
>solve({a1^2*alpha+a2^2*beta=a1, 2*a1*a2*alpha+a2^2*gamma=a2, a1*b1*alpha+a2*b2*beta=b1, a1*b2*alpha+a2*b1*alpha+a2*b2*gamma=b2, b1^2*alpha+b2^2*beta=a1+b1, 2*b1*b2*alpha+b2^2*gamma=a2+b2, a1*b2<>b1*a2},{a1,a2,b1,b2});
>convert(%,radical);

A couple of question on the following snippet.

Hi,
I am having trouble with the list L:=["2", "abcde"]. I want to get L[1]/4=.5. But L[1] is not a number. How can I convert that?
Thanks.

I am creating help pages for a package, and want an example worksheet to open as a worksheet rather than a help page. For example, clicking the "Package Overview help page template" hyperlink on the "Templates" help page brings up a worksheet rather than a help page. The mouseover of the hyperlink implies it was saved as a help page (presumably in a help database) rather than as a worksheet.
I see the active=true option under INTERFACE_HELP, but am not sure how I convert my worksheet to this form - surely I would lose the formatting styles.
An option under "save to database" seems logical, or an active=true option for makehelp, but these do not seem to exist.

Ref: Kahan (Jan 2007): How Futile are Mindless Assessments of Roundoff in Floating-Point Computation ?

I wanted to know, how Maple behaves on the example given in \2475 of that working paper (where other

systems are considered, mostly Matlab) and thought it might be of interest here in the forum.

**> restart; Digits:=16; interface(version);**

restart; interface(version);
Classic Worksheet Interface, Maple 10.06, Windows, Oct 2 2006 Build ID 255401
expr:=hypergeom([1-I*a,1-I*b],[1],x);
convert(expr, hypergeom, "lower c");
expr := hypergeom([1 - a I, 1 - b I], [1], x)
0
Digits:=14:
subs(a=1, b=2, c=1, expr):
eval(%,x=2); evalf(%);
#Re(%%%); plot( %, x=-1..0.9); plot( %%, x=1.1 .. 3);
hypergeom([1 - I, 1 - 2 I], [1], 2)
0.010385802579659 + 0.068521539093061 I

Hi
Am having trouble converting a list to a string. Below is my Maple code:
restart:
#To read in a list of letters find all #possible words which they can make in #dictionary
with(combinat);#, powerset
ps:=powerset([a,b,c,a]);
#Find all permutations of the letters in each list
p1:=permute(ps[10]);
#Convert list to string
convert(p1[1],string);
Final part of Maple output
p1 := [[a, a, c], [a, c, a], [c, a, a]]
"[a, a, c]"
What I really want is "aac" - how do I clear the list parentheses and commas?
Thanks
David

Hi,
Is there an easy way to convert Matlab or C code to something that Maple can use?
I know CodeGeneration in Maple can go the other way, but can't import into Maple.
Thanks!
Andy

I would expect, that evalhf works for that without 'manual' translation ...
restart;
interface(version);
Classic Worksheet Interface, Maple 10.06, Windows, Oct 2 2006 Build ID 255401
tst1:=proc(a,z) (-z)^(-a); end proc:
evalhf(tst1(1.5, 2.5));
Error, fractional power of a negative
'(-z)^(-a)': '%'= convert(%,exp);
tst2:=proc(a,z) exp(-a*ln(-z)); end proc:
evalhf(tst2(1.5, 2.5));
(-a)
(-z) = exp(-ln(-z) a)
-9
0.155662521299999988 10 + 0.252982212799999995 I