MaplePrimes - Questions and Posts tagged with product

product versus mul

fbackelj — Thu, 26 Apr 2012 13:49:08 Z

Hello,

Just a small question: what's the difference between writing

product( (2*i-1) mod 3 + 1, i=1..10 )

which incorrectly gives 105411381075, and writing

mul( (2*i-1) mod 3 + 1, i=1..10 )

which correctly gives 432...

And what's the reasoning behind this?

-- Regards,

Franky

Can we optimize Matrix-Vector operations with the LinearAlgebra package or is O(n^3) ~ O(n^2)

viraghj — Mon, 27 Feb 2012 18:31:01 Z

The following example shows some typical computations with Householder- or reflextion matrices. Why are the second and third variants only slightly better than the first one? Could we get a real speedup without rtable/NAG/BLAS/etc. tricks?

$ maple15
|\^/| Maple 15 (X86 64 LINUX)
._|\| |/|_. Copyright (c) Maplesoft, a division of Waterloo Maple Inc. 2011
\ MAPLE / All...

Matrix Integration

serena88 — Tue, 14 Feb 2012 16:36:47 Z

Hi, was wondering if there is a way that i can integrate each element in my matrix?

N0:=zeta->Matrix([[-2*(1-zeta)*(zera-1/2)],[4*zeta*(1-zeta)],[(2*zeta)*(zeta-1/2)]])^%T ###1x3 matrix

N1:=zeta->N0(zeta)^%T ###3x1 matrix

dot product of N0 and N1 is a 3x3 matrix

Can in integrate the 3x3 matrix? each of the element by zeta from 0 to 1.

Please advice. Many thanks. =D

Dot product of real vectors

Robert Israel — Thu, 24 Nov 2011 04:18:54 Z

The "." notation for the dot product of Vectors is very convenient and intuitive. For example:

> <1,2,3> . <1,1,1>;

6

One sometimes annoying feature of it, however, is that by default Maple is using a dot product (suitable for Vectors with complex scalars) that is conjugate-linear in the first argument. But let's say you will only be working with real scalars. There's no problem if your Vectors have numeric entries, but...

How can I calculate this product?

aryan_ams — Fri, 04 Nov 2011 20:20:46 Z

ex:

for N=4

Product of lists

Alaza — Wed, 05 Oct 2011 07:30:18 Z

Hi there,

I am working on a Maple sheet where I've been doing all the calculations with units. The problem is that I now want to get the product of a "seq" "R_DC_total-sek" and multiply it by the sequence R_AC_total-sek. But how do I do that? I've tried changing them into lists, but since one of the lists have units and the other one do not, Maple does not multiply the two lists, but just prints them.

I've uploaded the sheet here:

http://www.2shared.com/file/4sUmrdn0/EFD_N87_10_5_3...

Vector Calculus Multiply Error

AlwaysLearning — Fri, 10 Jun 2011 23:30:56 Z

Defined a demand function:

x:=(p,w)->w/(p[1]+p[2]+p[3])*Vector([p[2]/p[1],p[3]/p[2],p[1],p[3]])

The Slutsky Matrix is calculated as Dpx(p,w) + Dwx(p,w) x(p,w)^T with Dpx(p,w) = Jacobian for p1, p2, p3 and Dwx(p,w) is a column vector of the derivate of x1, x2, x3 in respect to w.

Step by step:

Dxp := Jacobian(x(p,w),[p[1],p[2],p[3]])

yields the correct Jacobian.

For Dwx I've tried several different methods, i.e.

Dwx := Jacobian(x(p,w),[w...

Announcing Maple T.A. 7 and Maple T.A. MAA Placement Test Suite 7

eithne — Mon, 10 Jan 2011 18:28:50 Z

Maple T.A. 7 and Maple T.A. MAA Placement Test Suite 7 are now available.

Maple T.A. 7 provides new options for analyzing grades and gaining a deep understanding of how students are performing, including:

Instructors can view all responses to an assignment question, to easily look for patterns
The grading scheme for the entire course can be defined inside Maple T.A., with appropriate weightings and flexible policies for dealing with missed, repeated, and worst assignments...

How to write matrix inequalities (restriction for optimization)

jean-jacques — Fri, 10 Dec 2010 06:39:14 Z

Hi e-friends,

I want to minimize a function subject to a set of S restrictions.

The restrictions are related to matrices V, W, X and Y:

V = [v1, .., vS] order L x S

W = [w1, .., wS] order L x S

X = [x1, .., xS] order LxS

Y = [y11,.. yS] order L x S

How may I write in MAPLE in compact form the following S inequalities (for any arbitrary integers L and S)?. ...

How to find product

hirnyk — Fri, 19 Nov 2010 11:22:21 Z

Maple does not find the product
product((k+a)*(k+b)/((k+c)*(k+d)), k = 1 .. infinity) assuming a > 0, b > 0, c > 0, d > 0, a+b = c+d;

GAMMA(c) GAMMA(d) infinity
----------------------------------

"Error, (in int) wrong number (or type) of arguments"

ap8888 — Fri, 15 Oct 2010 14:31:51 Z

After fixing the problem outlined in a previous post, I seem to get another error that I can't explain.

"Error, (in int) wrong number (or type) of arguments" is the product of defining a function 'u(r,theta,t)' and then defining each of its components.

I've attached the file here as well. Could someone help with troubleshooting? MapleMem5.mw

New packages in App Center

eithne — Fri, 24 Sep 2010 14:01:04 Z

I just wanted to let everyone know that we recently added some interesting new packages to the Application Center. These packages had been available as third party products. Now, the authors have chosen to make these products freely available to the community through the App Center. Follow the links below to take a look.

Harmonic Analysis

Structural Mechanics

Quaternions

FuzzySets

New edition of Math Survival Kit now available

eithne — Mon, 30 Aug 2010 20:26:43 Z

A new edition of The Mathematics Survival Kit – Maple Edition is now available. It contains 25 new topics, which were created in response to requests from readers of the first edition of the book. New materials range from basic operations such as factoring and fractions, to graph sketching, vectors, and integration.

The Math Survival Kit gives students the opportunity to review exactly the concept or technique they are stuck on, learn what they need to know,...

New verison of the Placement Test Suite is now available

eithne — Wed, 04 Aug 2010 19:01:52 Z

A new version of the Maple T.A. MAA Placement Test Suite is now available. The latest release includes a new Calculus Concepts Readiness Test, based on modern research into calculus assessment. It also includes performance improvements when dealing with large student populations, and tools for integration with Moodle™ and other course management systems. To learn more, visit What’s New in PTS 6