## How to plot the Bode plot of this transfer functio...

> restart:
with(DynamicSystems):
> sys := TransferFunction(1/((1+0.1*s)(1+0.002*s+0.0001*s^2)));
> BodePlot(sys,range=10^(-1)..10^(3));

I get the following warning:

Warning, transfer-function(s) are not rational-polynomial(s) in s

Why?.. How can I make it work without any warning?

Thanks everybody for help!

## with(OrthogonalExpansions)...

Hi,

with(OrthogonalExpansions) not working in Maple 15 (work in Maple 14). What is the equivalent package for FourierSeries calculations?

Kamel Boughrara

## Delete rows in a matrix...

Hi,

How can i delete a row in a (2D) Matrix?

Thanks,   (Mohsen)

## Sleep Sort

by: Maple 15

Sleep Sort is a hilarious (to me anyway) joke dressed up as a sorting algorithm.

Here it is in non-obfuscated (if somewhat garbagey) Maple code (need version 15 since it uses ?Threads,Sleep )

SleepSort := proc(L::list(posint),\$)
local Lout, p, i;
Lout := NULL;

p := proc(n::posint,\$)
Lout := Lout, n;
end proc:

## How to linearize three nonlinear equations?...

Hello friends,

I have tried to linearize three nonlinear equations which are coupled in the form of:

a1*xdot(1)+a2*xdot(2)+a3*xdot(3)=f1(x1,x2,x3)+u(1)

b1*xdot(1)+b2*xdot(2)+b3*xdot(3)=f2(x1,x2,x3)+u(2)

c1*xdot(1)+c2*xdot(2)+c3*xdot(3)=f3(x1,x2,x3)

the ai, bi, ci parameters are constant parameters and x1, x2, x3 are variables (states). also, u(1) and u(2) are inputs to the system. xdot(i) is the derivative form of xi.

## Maple 15 failed to connect to the kernel...

I am not able to use the Maple 15, because after it starts up, I receive an error ""the kernel loader cannot find Maple engine..."

What does it means and how to solve it?

Thanks

## Vector Calculus Multiply Error...

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...

## Equations of motion to state space...

Hello:

I am in need of help with Maple Linearize and an exremely crypitc and most un-helpful error message. What does this mean:

> linmod := Linearize(syss, parm, linp);
Error, invalid input: Linearize uses a 4th argument, linpoint (of type {list(`=`), set(`=`)}), which is missing

I can find nothing in the help in this.

Linearize works fine when running a sample program from the help files, but fails when I run my equations.

## trial version of Maple 15...

Could you tel me, is it possible to get free trial version of Maple 15?

## Enumerating Small Magmas

by: Maple 15

Introduction

The Magma package introduced in Maple 15 includes the command Enumerate. This routine allows you to count, or list, isomorphism class representatives of magmas of a given (small) order satisfying a selection of properties that...

## Changes in sqrt for Maple 15 — procedure versus...

by: Maple 15

Hello all,

I've noticed that something has changed to the type of sqrt in Maple 15, which breaks backward compatibility...

In Maple 14, we have

> type(sqrt,procedure);          true
> type(sqrt,`module`); false
> eval(sqrt);          proc(x::algebraic, f::identical(symbolic))  ...  end proc

while in Maple 15, we have

> type(sqrt,procedure);          false
> type(sqrt,`module`); true

## Source Code Versioning and Control for MapleSim...

I'm putting together what will eventually be a rather large simulation system that I want to be able to maintain across a reasonably large organization. Do you have any recommendations for Source Code Control/Versioning systems that work with your .msim file format or should I resign our team to exporting/importing code back and forth into Modelica for source control?

Thanks.

## Box Discretization Method-????...

Can anyone explain the method that was followed in "Box Discretization" scheme in Maple Help?

Am trying to discretize 4th order terms in space..... d^h/dX^4 and third and second order in the same way....

## Checking for subquandles using Magma:-IsSubMagma

by: Maple 15

The Magma package in Maple 15 includes the command IsSubMagma.  This tests whether a specified subset of a magma is closed under the binary operation that defines the magma.  For example, consider the following Cayley table for a group of order four.

> with( Magma ):
> m := << 1, 2, 3, 4 |