Unanswered Questions

This page lists MaplePrimes questions that have not yet received an answer

Hello there,

 

When I was trying to solve a differential equation with dsolve, I've got such a error report:

> dsolve({Q(0) = F[Az], diff(Q(x), x) = q[2](x)});
Error, (in dsolve) found the following equations not depending on the unknowns
of the input system: {Q(0) = -(1/4)*l^2*q[0]-(1/4)*l^2*q[0]*exp(2)+F}
 

But if I only write:

> dsolve(diff(Q(x),x)=q[2](x));

then there is no problem. 

Could i manually reset status bar (i.e. memory and time values)? restart; doesn't help.

raw_panel_cuttin.doc

 Given a large rectangular wooden panel, you want to cut specific quantities of smaller rectangles from it.

Ok, when I run the below code which maximize the risk adjuested portfolio returns
(long and short positions) in QP matrix form on empirical data I get very strange
allocations ie we go 100% or 100% short in almost all stocks except for a few
where the allocations are more appropriate like 0.2 etc.


# Maximize Risk Adjuested Return Matrix Form
# Minimize W'.Cov.W−W'.EV
# R=Return Matrix

EV := Vector([seq(ExpectedValue(Column(R, i)), i = 1 .. N)], datatype = float[8]):

to find the maximum number of rectangles that can be orthogonally packed into a larger rectangle:

http://lagrange.ime.usp.br/~lobato/packing/run/index.php

1) can some maple code replicate this?

2) but what i really want is: what arrangement of a given a number of rectangles (of differing widths and lengths...

Hi everyone,

I am importing an .m file from MATLAB to Maple using the command: FromMFile(). The .m file uses a set of huge symbolic matrices with an output of a huge symbolic vector of 36 by 1. Each element of this vecot is supposed to form a second-order differential /or algebraic equation that I am planning to solve using the Maple DAE toolbox.

The problem I have is that while I execute the worksheet, Maple only evaluates the...

If you look at Maple help on Grid[Launch] command there is an example of checking the prime numbers.

I do not understand why the timingData variable is empty after specifying it in exports parameter.

When I do not specify it in the exports parameter, the timingData variable has the same value as it had before calling Launch command.

I don't know why maple can't solve this PDE

> restart;

> PDE := 4.2000*10^6*(diff(u[1](x, t), t))-.445*(diff(u[1](x, t), x, x))+4200.*u[1](x, t)+464.82-20836.*x-15.832*t+4.0442*10^5*x^2+2953.7*x*t+0.14631e-1*t^2+9.6788*10^6*x^3-2.7139*10^5*x^2*t-.99786*x*t^2+0.15902e-4*t^3-1.0085*10^9*x^4-6.3082*10^6*x^3*t-1069.3*x^2*t^2-0.15006e-1*x*t^3-3.9073*10^(-8)*t^4+2.3478*10^10*x^5+2.5874*10^8*x^4*t+1.2265*10^5*x^3*t^2+2.9028*x^2*t^3+0.17521e-4*x*t^4+1.9407*10^(-11...

I'm using Maple 15 with Suse Linux 11.4

Export to latex produces a tex file which, when conveted by pdflatex contains all sorts of errors. The page margins are very large, parts are missing, the title appears alone on a page, lists of equations don't have line breaks so, for a long list you find just the central part going from edge to edge of the page.

I gave up using "Export to latex" on earlier versions. I had thought that Maple 15 might be better, but it seems worse.

 

The Physics package appears broken for the tensor product of Bras and Kets.
It is not possible to describe new operators creatde by the tensorial
product of operators on two Hilbert spaces. ie H12 = H1 X H2

Download BraKetTensorProduc.mw

Am I missing something here.

Thank you for your help

I have problem because mserver.exe stopped working

 

Yesterday that file was working very well.

 

help me please

robot-circulo-botone.mw

 

 

Three things - one being an possible business opportunity (albeit a small one) for Maplesoft ... ps. sorry for the lengthy talk

updates - Under the Table of Contents in the help Browser I can go to System -> Information -> Updates and find the What's New updates in all versions up to and including the one you're using.  Then at the bottom there are links to further explicit updates to which there are no links in the searchable browser (at least that I could...

Greetings All

I have several equations and each have their own individual frequencies and amplitudes. I would like to sum the equations together and adjust ONLY the individual phases, phase1,phase2, and phase3 to keep the total amplitude value of eq_total under a specific value like 0.8. I know I can normalize the signal or change the vertical offset, but for my purposes I need to have the amplitude controlled by changing/finding the values for just...

When Benoit Mandelbrot was still alive I sent him an email:

Hi,
I am writing to you because I have trouble understanding why
the covariance function in the Fractional Brownian Motion (FBM) is given by:

(t[i]^(2*H)+t[j]^(2*H)-abs(t[i]-t[j])^(2*H))/2)

I would be very grateful if you could please explain this to me in simple and step by step terms.
I understand simple ARIMA models (P(t)=P(t-1)+E(t) where E(t)=p*E(t-1)+r(t)) which have the
same...

 

Hi all,

 i have a problem with the equation generation in MapleSim, when using spring/damper elements in a Multibody-System. As an example, I've created a model of a mass-spring-damper system:

 

 


 

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