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Why not put the entire Maple help-system online? I mean, as html. No served .mw or plugins. No huge .pdf downloads. Just the goods, one page per routine, that load and render fast for every half-decent browser. No registration and login would be nice too. Consider the competition's sites, here and here. Wouldn't that be another...

Plouffe's Inverter...

December 07 2007 acer 10181 Maple

A new version of Plouffe's Inverter was announced by its author today in the usenet group comp.soft-sys.math.maple . That usenet posting gave this link to maple code for the inverter.

It also said this, "As usual, I would like to mention that this program is FREE and can be distributed at will, I just wish that the source is mentioned. Simon Plouffe"

"I've seen this element before..." Often we are faced with the problem of building up sets incrementally, by removing pieces one at a time from a larger whole. The bottlenecks in this case are usually: 1) adding a small set X to a large set S (copies S and X, making this ~O(|S|+|X|)) 2) removing elements of the large set S from the small set X (binary search: |X|*log(|S|)) A classic example of this is a breadth-first-search. We start at one vertex of a graph and in each iteration we add the set of new neighbors X to the set of vertices S that have already been found. We can make this more useful by making the program return the sets of new neighbors found in each iteration, that is, the sets of vertices that are distance 1, 2, 3, etc. from the initial vertex.

When working with large sparse linear systems you often want to look at their non-zero structure, however Maple's existing tools are all designed for dense matrices. I wrote a little tool to produce images like this in reasonable time. You can download the code here, and the rest of this post is a quick tutorial on how to use the included command. Maple 11 is required.

What is the largest linear system that Maple can solve? You might be surprised to find out. In this article we present strategies for solving sparse linear systems over the rationals. An example implementation is provided, but first we present a bit of background. Sparse linear systems arise naturally from problems in mathematics, science, and engineering. Typically many quantities are related, but because of an underlying structure only a small subset of the elements appear in most equations. Consider networks, finite element models, structural analysis problems, and linear programming problems.

For double-precision ("hardware") real and complex floating-point operations on Matrices, Vectors, and Arrays Maple makes use of its external-calling mechanism to get to compiled code. A great deal of such compiled code for array operations requires what are known as Basic Linear Algebra Subprograms (BLAS). The BLAS libraries provide support not only directly for Matrix-Vector arithmetic but also indirectly in other external compiled libraries used by Statistics, ArrayTools, LinearAlgebra[Modular], etc.

In the admirable quest to make Maple better and stronger, and since so few people responded to the Suggestion to add a searchable bug database here on mapleprimes, here's another tack.

What are the fewest keystrokes that can make the TTY commandline interface of Maple 10.06 or 11 crash?

By crash I mean something like bus-error or segmentation-fault, stack-limit-exceeded, or lost-kernel-connection. I don't mean a runaway computation that simply consumes all...

Can anyone explain to me why the argument of the innerproc, which as y is a local of the outerproc, gets evaluated more than one level?

innerproc := proc(t)
print(t[1]); # or dismantle, or lprint
end proc:

outerproc := proc(x)
local y;
y := x;
print(y[1]); # or dismantle, or lprint
innerproc(y);
end proc:

outerproc(vector(1,['exp(0)']));


acer

Maple 11 has been out for a while now so hopefully people have it. I thought I would write a short post detailing some of what was done in the area of Groebner bases. If you run the examples in Maple 10 and Maple 11, I would appreciate it if you could post the times and the specifications of your computer.

Many Maple users have a preference of user interface, whether it be command line (TTY), Standard (Worksheet or Document mode), or Classic. My personal view is that each may be suited for different types of task. While it's understood that Maplesoft is dedicated to supporting the Standard interface, I understand that some users remain devoted to the Classic interface.

I often use Maple 10 on a 64bit Linux machine, on which the performance of the 64bit Maple 10 kernel is comparatively faster for some types of computation. I discussed this briefly in an earlier post. But there is no officially released 64bit Linux port of the Classic interface. So below I'll mention an unofficial and unsupported way to use the 64bit Linux Maple kernel with the 32bit Linux Maple Classic interface.

Maple 10 comes in both a 32bit and 64bit version for Linux. It's possible to run both versions, installed to the same base location, on a machine with the appropriate operating system runtime configuration. There are some interesting performance differences between the two versions.

I'll say a few words about the installation. I installed both under /usr/local/maple10 on an Athlon64 3200+ running the x86-64 version of the Fedora Core 2 operating system. I have the 32bit...

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