## get Maple to use full evaluation in a function cal...

I don't understand, why maple has problems with the following command:

Output_Curve_test:=plot3d([0,0,iL_RMS_func_Ue_const(Iatest,U_test)],Iatest=0..2,U_test=0..1);

It seems that Maple doesn't call the funciton iL_RMS_func_Ue_const with the function variables Iatest and Utest. Instead it just uses the variable names Iatest and Utest. I get the error message:

Error, (in iL_RMS_AVG) cannot determine if this expression is true or false: 46.87500000*Iatest <= .1250000000*(1500-1500*U_test)*U_test

How do I get Maple to use the actual Values of Iatest und U_test? Below are the functions which are related to the problem.

## plot a pair of data?...

Hi, All, Please look at this example. I am using Newton's method to solve for the equation x^2-a=0. > restart: > Digits := 30: > f :=x-> x^2-a: > df :=x-> 2*x: > for a from 1 to 6 do > x0 := trunc(sqrt(a)): > for j from 1 to 5 do > x1 := x0 - f(x0)/df(x0); > x0 := x1; > rsd := f(x0); > end: > printf(`%3.10f\t %3.10e\n`, x0,rsd): > end: Now, I want to plot the solution x and the residue rsd against a in 2 separate figures, how to write the code? David

## Matlab commands from Maple...

I've been exploring the link between Maple and Matlab, and there seems to be no documentation on how to use Maple to call commands (or .m files) in Matlab. On the other hand, it doesn't state that this is not possible. Has anyone else looked into this?

## How do I use Digits within a procedure?...

I am trying to create a procedure like this: myproc := proc(x) Digits := x; sqrt(x) end proc; and then I want to plot the results like this: plot(myproc(x), x=2..20); However, I get an error: "Invalid assignment to Digits". The following works fine, however: seq(myproc(x), x=2..20); How can I solve this? Thanks.

## Using Maple 10 documents for presentations?...

It's obvious how to use Maple 10 for creating a document, but has anyone used Maple 10 for presentations? I'm going to present in a seminar in a couple of weeks and have some Maple demonstrations and graphics to show the group. I'd be interested in hearing tips, suggestions, experiences and ideas for presenting mathematical content to a group from within Maple. (I'm familair of course, with Powerpoint and LaTeX slides, and the LaTeX Prosper package. I'd use LaTeX/Prosper except that then I have to embed the Maple in the presentation. It would be more convenient if I can use Maple solely.)

## Solve an ODE with mixed boundary condition...

Dear All, First of all thank alec and Prof Doug. Please refer to post http://beta.mapleprimes.com/node/362#comment-729 My problem is to solve the following ODE with constrain given by the Eq: > DEq := diff(f(x),x) = c1*sqrt( g(f(x)) - g(f(x=x1)) ); > Eq := ug - f(x=0) = c2*sqrt( g(f(x=0)) - g(f(x=x1)) ); > g(f(x)) := exp(f(x)-xn) +exp(-f(x)) +(1-exp(-xn))*f(x); where ug is the independent variable and others are parameters > c1 :=-257753830.552993398770016153893; > c2 :=1.40376701562707174099362643812; > xn := 35.4196679725860384893589519100; > x0 := 0; > ug := 40; I have tried to followed alec's suggestion but the solution sometime still cannot be obtained. The independent variable ug has to be varied from -50 or less to + 100 or more. The intial guess in solving f0 (f0 := fsolve(g('fx0'(f0))-gfx0(f0),f0=30);) has to be input manually, this is a big drawback.

## exporting 3D files to Povray...

> Hello all, > How do I export a Maple 3D plot to Povray 3.6 Win ? > I use Maple 8. > Some animations on my site http://www.artdigits.org > Answer please to: avandergoten@skynet.be > Thanks for the help !! > Andre

## piecewise & color

by: Maple
Hi, Colleagues, I need to use two colors for positive and negative values of a plotted function and I am trying to use a piecewise switch. My atempt was something like plot(sin(x), x=0..13, color=(x->piecewise(sin(x)

## How do I get my procedure to work?...

What does "Warning, `delta_Ia_con_p` is implicitly declared local to procedure `inductor_current_RMS_AVG_p`" exactly mean?

I get this, when I execute the following procedure:

# art=0 returns RMS current and art=1 returns AVG current
> inductor_current_RMS_AVG_p:=proc(Ue,Ua,Ia,L,T,art)
>
> delta_Ia_con_p:=(Ue-Ua)/L*Ua/Ue*T;
> inititial_inductor_current_con_p:=Ia-delta_Ia_con_p/2;
> initial_inductor_current_p:=piecewise(Ia<eval(IaLG_boundary_condition), 0, inititial_inductor_current_con_p);
> # initial_inductor_current_input:=initial_inductor_current;
> inductor_current_increase_p:=initial_inductor_current_p+(Ue-Ua)/L*t;

## Mandelbrot Set and Newton's Method Basins of Attra...

Maple
This blog entry evolved from my reply to Moira Chas's post. I want to thank her for initiating such an interesting topic. Usually Mandelbrot set is drawn in Maple using `plot3d` command. That also can be done using `densityplot`. In the example below I use `mandelbrot` from John Oprea's worksheet,
```mandelbrot := proc(x, y)
local c, z, m;
c := evalf(x+y*I); z := c;
for m to 50 while abs(z) < 2 do z := z^2+c od;
m end;

plots[densityplot](mandelbrot,-2 .. 0.7, -1.35 .. 1.35,
s_tyle=patchnogrid,colorstyle=HUE,numpoints=62500,axes=none);```

## How to control the thickness of axes and tickmarks...

by: Maple
Hi, Colleagues, I need strongly reduce Maple generated graphs for a journal publication. How could I make the axes and tickmarks thicker? Thanks, Evgeni

## Plot3d and color....

Why do I get the same output with the two following statements plot3d(0, 0..20, 0..70, color=proc(x,y) 200000*x end proc); plot3d(0, 0..20, 0..70, color=proc(x,y) x end proc); How does the option "color=proc() ..end;" works? How can I choose the colors? (The reason behind my question is that I am trying understand how to plot the Mandelbrot set)

## Plotting Matrix[x,y]?

by: Maple
SOS! I need to find how to plot y=f(x) if x and y are columns of 2D matrix. Thanks, Evgeni

## ... save a module containing "define_external" as ...

I have a module with an exported procedure defined by `define_external`, like this:
``` loadtest := module() export hb; option package; hb:=define_external( `hb`, `MAPLE`, `LIB`="/home/hans/system/maple/libhb.so"); end module: ```
This works if I put the code above into a .mpl file, and use `read` to load it. The problem is that I would like to save this module to a maple library:
``` > libname; "/home/hans/system/maple", "/usr/local/maple8/lib" > savelibname:="/home/hans/system/maple/loadtest.lib": > march('create',savelibname,100); > savelib('loadtest'); > map( march, [ 'gc', 'reindex', 'pack' ], savelibname ): ```
``` > A:=Matrix([[3,2,1,-2,-1,-4],[1,0,1,0,-1,0]]): > with(loadtest); [hb] > hb(A); [3 2 1 -2 -1 -4] CALL_EXTERNAL([ ]) [1 0 1 0 -1 0] ```