Hi. I run Maple on 64-bit linux. I have tried to run the same commands from xmaple and maple I do not get the same result. I would very much like to be able to create postscript graphs from the command-line. However the result of the commands at the bottom of the screen is a black graph, which is NOT logarithmic. However when I run the same commands from the xmaple, the results work perfectly - a red graph on a logarithmic plot. The commands are: plotsetup(ps, plotoutput="graph.ps"): plot(exp(x), x=1..20, color=red, axis[2]=[mode=log]);

sum(1/(n^4+n^2+n),n=1..infinity);

  -infinity

                         /   -----                               \
                         |    \                2                 |
        signum(-1 + 1/31 |     )      (4 _alpha  + 13 - 6 _alpha)|)
                         |    /                                  |
                         |   -----                               |
                         \_alpha = %1                            /

         + gamma + 1/31

        /   -----                                               \

Has anyone compared timings of Maple executing under Windows XP and Windows 7? It means, with the same PC and booting in either OS.

The subs command uses variables assigned to values that sub into an equation so the original equation being subbed into is not changed.  Wouldn't it be nice to assign variables during a subs command as well?  I don't really think it adds any value but it would make the command a little more versatile. 

Hi,

This is a bug in v13.01 (I haven't yet tried 13.02). I'm not sure it's related to the proc or recursion but using "Sum" instead of "add" in this case yields the wrong result. I have used "Sum" in recursive definitions before without a problem but this particular one reveals a bug. Given the recursive function:

This first situation may or may not be a bug.

 

restart;

Student[Calculus1][CriticalPoints](x^2, x=-2..2);

interval := -2..2;

Student[Calculus1][CriticalPoints](x^2, x=-2..2);

Student[Calculus1][CriticalPoints](x^2, x=interval);

 

Notice the change in output when the variable "interval" has a value.

The second situation is definitely a big problem:

restart;

ode1:= diff(y(x),x) = y(x)*(y(x)-1)*x;
ode2:= diff(y(x),x) = y(x)*(y(x)-1)*(x-a);

Here is a simple bug:

If I define a function f via

>f:=x->solve(-x*(x+1)+y^(2/x),y);

I can plot(f(x), x=0.2..5) and evaluate f(3) but plot(f,0.2..5) yields an error message ( wrong argument  (f) in plot) and f(1.5) crashes Maple 12–connection to kernel lost.

If I define the function using fsolve or using unapply as in
> g:=unapply(exp((1/2)*ln(x^2+x)*x),x);

I can plot(g,0.2..5) or plot(g(x),x=0.2..5) or evaluate g(1.5) without problems.
 

Any idea whee the bug is?

 

What are some good 3rd party add-ons for maple? 

Maple Advisor Database?  it's a little dated but I think a nice addition.  or Aladjevs library for Maple 2.2013 ? - what does this really add to Maple that it doesn't already have? 

Any comments on those or some other good suggestions?

I recently came across a Probability and Statistics - Explorations with Maple book by Karian and Tanis.  It mentioned something about a stats package.

It seems that most of the stats package commands are mostly incorporated into newer maple versions. 

However some commands from the stats package seem to be better.  For example

Mean([x,3,1+x])  produces an error with the Statistics package in Maple where using Mean from the Stats package of Karian and Tanis produces a result. 

Hi, i am trying to find cosets of S_3 in Maple. I have done this so far: > restart; > with(group); > S_3 := permgroup(3, {[[1, 2]], [[1, 2, 3]], [[2, 3]], [[1, 3]], [[1, 3, 2]]}); permgroup(3, {[[1, 2]], [[1, 2, 3]], [[2, 3]], [[1, 3]], [[1, 3, 2]]}) > grouporder(S[3], ident); Error, (in group:-grouporder) expecting a permgroup or a grelgroup, but received S[3] > Group order should be 6 (which is 3!) but for some reason it does not work. Also I am getting an error message when I try to find cosets of S_3. > ident := permgroup*(3, {[]}); > cosets(S_3, ident);

If I highlight some text in the first line of a document and then wish to highlight text of the same color on the next line, and if the highlight color touches the one above in any way then a whole block is extended and highlighted for both lines.  

However it seems to be okay if different highlight colors are used.

I have developed a fairly complicated (by my standards) Maple routine that makes heavy use (again by my standards) of the numeric methods dverk78 and rkf45. Recently I posted about differences I seemed to be seeing between running this on Linux and on windows. I was in error; the difference seems to be between Maple 13 and Maple 11. Maple 13 gives the same answers on Linux and on Windows.

A favorite diversion of mine (and of many around the Maplesoft office) is xkcd. Its author, Randall Munroe, bills it as “a webcomic of romance, sarcasm, math, and language.” Since 2005, he’s been entertaining many self-proclaimed geeks with his unique and slightly skewed jokes on technology, computer science, mathematics, and relationships.

I really like the post in which a substitute teacher – hm, Mr. Munroe......

Does Maple 13 still have strange behaviours with empty sums like M12?

  interface(version);
  Classic Worksheet Interface, Maple 12.02, Windows, Dec 10 2008 Build ID 377066

  #Sum(t^j*(z-a)^(-2*n+j)/j!,j = 0 .. -1+n); eval(%, n=1);
  #S:=Sum(t^j*(z-a)^(-2+j)/j!,j = 0 .. 0);
  S:=Sum(1,j = 0 .. 0);
  value(S);
  #subs(Sum = add, S); value(%);
  #eval(S, Sum = add);
  #eval(S, Sum = sum);

I have constructed a Maple routine which makes multiple calls to the dsolve numeric methods rkf45 and dverk78. I have been running on Windows Vista. Recently I began experimenting with Kubuntu Linux, thinking this might run faster. I was surprised to see that the same routine with the same numeric input gives different results depending on whether it is run on Kubuntu or Windows.