Powerful database + Maple = Fun

Are you struggling to connect Maple with a simple microsoft access database?
Then after weeks of error messages you finally manage to connect just to
discover that the datafeed is slow slow slow ie you are driving a Fiat Punto
when you really should be driving a ferrari!

Then maybe OpenTSDB http://opentsdb.net/index.html is something for you.
OpenTSDB is free software...

Hi.

Some times ago, I have asked about possibility to solve multilayer transient heat transfer problem.
The problem was solved originaly by Robert Israel. I enclosed his solution and explanation in file Xpde_oryginal.mw.
Thank's Robert!


There was a problem with correct results of numeric PDE in Maple 14 when I have used convection and radiation BC toogather. However Maplesoft have removed this bug in version 15, thus now I have obtained right results...

I am a little disappointed in the update frequency of Maple. 

Maple 15 saw one relatively minor update and I don't foresee any more updates for this version before the next release which is unfortunate.  Then again, was Maple 15 refined so good that it didn't need much fixing?  Something tells me no, but please enlighten me otherwise. 

The threshold for updating seems to be getting smaller and smaller.  What I mean by that is, it seems...

I have always thought that regressions has been too complicated in Maple. 
The Fit command is too fiddly ie you have to specify too many things and 
it is easy to get it wrong plus the statistical output you get is far from 
mainstream ie you dont get t-values, p-values, R, R^2, Adj R^2 etc etc.

I have therefore designed a module called SReg with a new procedure called Reg()
which only needs one input and that is a datamatrix. It is important however that 

I wanted to set the background color of a plot to black (without axes shown) and figured I could add this to the PLOT structure: POLYGONS([[10,0],[0,0],[0,10],[10,10]],COLOUR(RGB, 0., 0., 0.))

And that worked fine. But I feel that it ought to be easier.

Liquid flowing in a pipeline has inertia.  If a valve at the end of the pipeline suddenly closes, a pressure surge hits the valve, and travels through the pipeline at the speed of sound. The damping effect of fluid friction gradually attenuates the pressure wave.

This phenomenon is called water hammer and can cause damage significant damage, sometimes even rupturing the pipeline.

The pressure wave often produces audible sound. If you’ve ever heard...

For your information.

The growth of the audience of russian Maple site webmath.exponenta.ru
According bigmir.net

 year        hits          visitors         hosts        

 2010      608 118    193 495     179 328
 2011  ...

I have come across this previously but I never had the energy to report it.
The problem is that there exist a bug in Vector[row] when n>10.

For example run the below code:

restart:
with(LinearAlgebra):
a1 := Vector[row]([seq(w[i], i = 1 .. 5)]);
a2 := Vector[column]([seq(w[i], i = 1 .. 5)]);

a3 := Vector[row]([seq(w[i], i = 1 .. 20)]);
a4 := Vector[column]([seq(w[i], i = 1 .. 20)]);

a1.a2;
a3.a4;

   ...

National Public Radio in the USA carries Car Talk, a humorous phone-in program in which Tom and Ray Magliozzi (Click and Clack, the Tappet Brothers) diagnose and offer solutions for mysterious auto-related maladies. It's an amusing hour on Saturday mornings.

Here's an example exhibited by Nusc, which I have tweaked slightly to make it look more like your mathematica example.

### Reference: http://www.mapleprimes.com/questions/36580-Bifurcation-Diagram

### xexpr is the logistic function to be iterated (we always start off at x=1/2, which will eventually attract).
### [ra,rb] is the range of the parameter.
### acc is the number of points sampled in [ra,rb]

Bifurcation := proc(initialpoint,xexpr,ra,rb,acc)

Maple is sometimes very forgiving, e.g. (this is in Standard GUI):

plot(x,'color'=blue); #ok
plot(x,'colour'=blue); #ok
plot(x,'colour'=BLUE); #ok

and sometimes not, e.g.

plot(x,'COLOR'=blue); #nok

Other example:

plot(x, 'style' = point, 'numpoints' = 10, 'symbol' = circle); #ok
plot(x, 'style' = point, 'numpoints' = 10, 'symbol' = CIRCLE); #ok
plot(x, 'style' = POINT, 'numpoints' = 10, 'symbol' = CIRCLE); #ok
plot(x, 'STYLE'...

It is possible to thicken the axes of 2D plots by adjusting the underlying data structure, since the appropriately placed THICKNESS() call within the PLOT() data structure is recognized by the Standard GUI. This does not seem to be recognized for PLOT3D structures, however.

The issue of obtaining thicker axes for 2D plots can then be resolved by first creating a plot, and then subsequently modifying the PLOT structure.

The same techniques could be used to thin...

Half of posts under firefox look cut. For example:

http://www.mapleprimes.com/questions/128564-Any-Way-To-Reclaim-NAG-d01akc-Allocated.

It depends on minimal font size. If set to 15 error can be seen.

Download 10102011.mw

As defined at http://mathworld.wolfram.com/MRBConstant.html the MRB constant is