I am working with Maple 9 and I am trying to create some kind of density plot similar to the one shown below this message (this one was created with matlab). I haven't yet figured out how to get a density plot with a color gradient and a scale (or legend) at the site of it which shows which color corresponds to which density value. Actually I want to plot a capacitor (or inductor) current and stored energy in an inductor (two different diagramms) which are depending on the input current and the output voltage. This should happen in a similar diagramm shown below. I would be very thankful if you could help me to solve this problem.

I've looked at Alec Mihailov's interesting web page describing how to use the Microsoft assembler (MASM) to create a DLL that can be called by a Maple procedure. I'm attempting to rewrite the code using the GNU assembler (as) and have a few questions. Page 331, section 6.2 of the Maple 10 Advanced Programming Guide states that, to create a DLL, "the external library functions must be compiled by using the _stdcall calling convention, which is the default under UNIX but must be specified when using most Windows compilers." This leaves me somewhat confused. My limited understanding is that the stdcall calling convention has two effects:

Here are some screenshots of Functioning Maple V R1 DOS demo (circ. 1991).

Recently I was asked in a private email about the fastest way of calculating of binomial coefficients mod 2 in Maple. It shouldn't be a problem for anybody reading my assembly dll creation manual. Anyway, here is the assembly code,

With Maple being able to access dll functions, it is easy to produce a function giving the epoch from the date and time. I give an example here for doing that with Open Watcom compiler included in Maple's distribution for Windows.

Hi does it happen to you that when you evaluate an expression in maple or maplet you get this message,"Evaluate_result"? What this really mean?

The help page for StringTools:-FormatTime states that the %Z specifier returns the time zone, if available. On my system (linux), it just returns the string "???". For example,

 StringTools:-FormatTime("%Z");
                                     "???"

Is there a way to get this to work?

Does anyone know if there is a way to create/display nested piecewise functions in maple? I want a piecewise function where the conditions are themselves piecewise functions. Is that even possible?

After analysing a sketch I came up with two equations describing the sketch.

My first equation looks like: eq1 := tan(X/2) = Vt/Hr;
My second equation looks like: eq2 := tan(X) = (V-Vt)/Hl;

I know the values for Hr, Hl, V so I am left with two unknown values which is angle X and distance Vt.

I have typed these equations in Maple 8 and when I substitute the values Hr, Hl, V then Maple does come up with the correct solution to either angle X or distance Vt. My problem is that I do not want the specific answer to this problem. I need a general answer. That means I want an equation where I can put in any legal values for Hr, Hl, V and then the equation will calculate either Vt or X for me.

Is is possible to add comments in Maple code without gyrating through the LanguageDefinition? Below is a sample that shows an embedded comment - it would be nice if this were possible.

fn := proc(n)
  local x;
  
  # here's my math
  x := n + n;

end proc;

C(fn);

int fn(int n)
{

 // here's my math
 x = n + n;

 return x;
}

Hello,

I'm trying to create a piecewise function with vectors instead of constants. So far I have

vf := 3*vx[1] < [6, 1] and vx[1] < [-2, 5], [3, 4]+3*vx[1], 2*vx[1] < [8, -4] and -vx[1] < [2, -5], [1, 9]+2*vx[1], -3*vx[1] < [-6, -1] and -2*vx[1] < [-8, 4], [9, 5]

This won't convert to a piecewise function. However, if the vectors are in the form (1,2) instead of [1,2] (ie. with parentheses instead of braces), it works. Is there any way to convert them at this stage or earlier, when I have then as individual functions (for example: 3*vx[1] < [6, 1])?

Thanks for the help,

Am

Hi Friends My name is Sayed Hoseini and I am PhD student in University of Wollongong. Could you please have a look on this problem and let me know about any package/s which might be used for solving that? I came across to this problem in my research: We have a linear system including two differential equations and two variables; For example consider the following system: L*U=H Where: [diff(,x$2)+I*w q ] L=[ ] [q diff(,x$2)- I*w] and [u(x)] U=[ ] [v(x)] that u and v are functions of x and w, q and H are functions of x too, but fixed and I is the complex argument .

Looking for faster ways to make chi^2 nonlinear fit calculations, for functions involving integrals, I have compared timings of calculation of chi^2 at a pair of sample points evaluating the integrals by three numerical methods. In the attached worksheet they are called as follows: 1. chin, using evalf(Int(...)) 2. chin2, using the interpolant option (`dsolve/numeric`(sys, range=...)) 3. chin3, using evalf(Int(...,method=_d01ajc)) I have obtained timings with Maple 9.5 using first a Celeron 333 MHz under RH7.1 and then a P4 1.8 GHz under Win XP. My expectation was that the method of the interpolant function were the

How do I create a shared library for use with the define_external command?

In the examples,ExternalCalling help page the following command is used.

> ssystem("cl test1.c -Fetest1.dll -Gz -link -dll -export:f1"):

But this assumes the Microsoft Visual C/C++ compiler.

I want to use the new Watcom compiler included in Maple 10 for Windows.

Bob.

It is quite frustrating how slow map or zip acts over rtables (examples below). I find it quite useful to write a separate procedure and use the new compiler abilities in Maple 10.