Hi,

I have a dual processor computer and I am using Maple 8 (because it is much faster than Maple 11) but I noticed that Maple 8 only maxes out one processor and doesn't use both.  I am using (unfortunately) Windows Vista.  I would appreciate any suggestions.

I also have a single 2.3 GHz processor at home with XP so I'll give that a try.

Thanks

Hi.

I think there is a problem with arrays. When i define an array like this:

A := {1,12}
Then it works fine as you can see:
print(A[1])=1
print(A[2])=12

but if i do it like this:
A := {1.1,12}
Then the results is reversed:
print(A[1])=12
print(A[2])=1.1

I'm running Maple 11 and updated to the 02 patch.

When I try to integrate a function,Maple returns a summation sign and underneath this sign is the expression R= RootOf (      ),where the bracket contains a cubic polynomial written in terms of Maple's internal default variable _Z.  Why can't Maple simply evaluate the roots of this cubic equation and return the value to me? What do I have to do to force Maple to return the desired result? 

AntipodeanMan

Hi there,

fsolve fails me, for the first time. I have this very messy expression, which comes out of a cubic equation. It must have a zero. I plot it and the graph, smooth, shows a zero between 16.4 and 16.5, but maple's fsolve fails to find it, why's that? The slope of the function is very flat near the zero. I tried to tell maple the solution is between 16.4 and 16.5, to no avail.

Any advice will be much appreciated. The following code tells it all.

many thanks,

Patrick.

I am having problems using implicitplot.  I run this code and it worked and today I tried it again and it gives me the following:

with(plots,implicitplot);

implicitplot(0=int(erf(  (T-e*t)/sqrt(2)  )*t^2*exp(-t/2),t=0..infinity),e=0..1,T=0..10);

Error, (in plots/implicitplot) invalid input: the following extra unknowns were found in the input expression: {t}

The weird thing is that this worked before (took about 10min though) and now it isn't.  Any suggestions?

Thanks

May be that some other people want to use pattern-matching techniques in wrong ways or contexts. What I am interested in is much simpler and clear.

Using dsolve gives the incorrect solution unless you force it to use Laplace transforms. 

Notice that Y5 is the correct solution, not the Y coming from dsolve.

DE17:=diff(y(t),t$2)+y(t)=Dirac(t-Pi)+Dirac(t-2*Pi)+Dirac(t-3*Pi);
Y:=dsolve({DE17,y(0)=0,D(y)(0)=0},y(t));
plot(rhs(Y),t=0..6*Pi);
with(inttrans):
Y2:=laplace(DE17,t,s);
Y3:=solve(Y2,laplace(y(t),t,s));
Y4:=subs({y(0)=0,D(y)(0)=0},Y3);
Y5:=invlaplace(Y4,s,t);
plot(Y5,t=0..6*Pi);
 

 

Anybody run into this problem before?

View 8340_helpweaklynonlinear.mw on MapleNet or Download 8340_helpweaklynonlinear.mw

A colleague recently showed me some strange behavior when trying to plot vertical lines. The following works to create the unit square:

plot( [x=0,x=1,0,1], x=0..1, y=0..1, color=black, axes=none ); # OK

But doubling the size in each direction does not produce a square:

plot( [x=0,x=2,0,2], x=0..2, y=0..2, color=black, axes=none ); # BAD

The vertical lines extend only up to y=1, not y=2 as requested. The next command shows that vertical lines at the boundary are treated differently.

How do I change the default font used in Maple 12?  I'm in WinXP.

Hi, I am just wondering who is currently using Maple in Finance. While I would keen to know any commercial or academic uses, I am especially interested in two areas: 1. Asset valuation and modelling 2. Portfolio analysis including risk, hedging, rebalancing or optimisation 3. High frequency (from 15min to readtime) processing of data (FX, Equity or IR) We recently completed a quite extensive benchmarking of Maple, Mathematica and Matlab using finance and portfolio related problems and would be interested know other experiences here.

I have been wondering about the reception of an independent patch Library for Maple.

I'll lay out a few ideas, and then maybe some criticism (or indifference) might follow.

I'm a bullet-point sort of person:

• sourceforge project with a few willing experts for vetting and gatekeeping of submissions.
• Patch .mla Library archive, going into /toolbox/Patch/lib/ so as to get picked up automatically by libname.
• Self-building, with...

I have been thinking about creating a Maple benchmark, to show a performance ranking versus operating system and hardware.

Is there any interest in such a thing?

If the results were put in a mapleprimes blog post, then they might be editable, and so could be updated as more items were submitted (messaged or emailed, to me, say).

After having Maple for a week I'm happy with it but still have to learn a lot about the kinds of problems it can solve.  Here is a problem I solved many years ago whose solution I have misplaced.  I'm wondering if Maple could help me recover my solution.

Write an expression for ab (a and b real) using only the unit (1) and the operations of adding, subtracting, and taking the reciprocal.

I'm also curious whether this is a well-known problem.  As I recall, I didn't find any references to it when I worked on it before.

 

Something I've been wondering about...