restart;
with(ArrayTools):
M1 := Matrix([[0, 0, b], [0, e, f]], order = Fortran_order);
row, col, var := SearchArray(M1);
M2 := Matrix([[0, 0, b], [0, e, f]], order = C_order);
row2, col2, var2 := SearchArray(M2);

I guess that's a bug.

Dear  i want to plot the graphs for different values of R[2,5,6.5]   here is the codes: Either ido loop or array i have to use or other procedure 

The graph display should be at R=2, one graph, R=5 another and R=6.5 

onemore graph

restart:
with(DEtools):
eta:=1+k*x+epsilon*sin(2*Pi*x):
A1(x):=-exp(-alpha*x)*J^2*R/(2*eta^3+6*xi*J^2*eta^2):

psi0:=A1(x)*y^3:
psi:=delta*psi0:
V:=-diff(psi,x):
delta:=0.1:
epsilon:=0.01:
alpha:=1:
xi:=0.001:
k:=0.1:
As:= [0, 2, 4]:
x:=0.2
plot([seq]([eval(V, J= A), y, y= 0..eval(eta, J= A)], A= As),title=" velocity at R=2.0 ",labels= ["v", "y"],color= [green, red, blue], linestyle= [solid, dash, dot],legend= [seq](J = A, A= As), axes=boxed);

Hello, I would like to customize the context menu in Maple 18 and looking for a way, to convert 2-D expressions to classical maple input using command(s) (same function as "2-D Math > Convert To > 1-D Math Input"). My main problem is, that using the standard procedures in the context menu I get the result of an expression, not the expression itself.

Can you give me an idea, how to do this? Thanks, Csaba

@Carl Love Dear Sir i am trying to solve the system of nonlinear ODE equation with semiinfinite domain by using shooting method . but i am receiving following error 

"Error, (in isolate) cannot isolate for a function when it appears with different arguments"

how can i remove this error. i am unable to find the mistake. kindly help me 

Hello! I'm really craving for a piece of advice from you pros.
For simplicity's sake let's start with this made-up system.

where

and

Here is solver options with pair of events to get idea about what I want.

Plot of solution



For my purposes it's essential to restrict variables m and D(fi1)(t), D(fi2)(t). While it's very convenient to use piecewise() operator in first case with m, I simply can't find working method for second.

I've tried various events for dsolve, but they trigger only once and I failed to provide continuous restriction on the derivatives in question.

That's what I need in the end:


If there's a way to obtain this result, please, don't make secrets of it :) Thank you in advance!

Hi!

I was trying to obtain the field equations for the QED Lagrangian and I was not sucessfull.

All my calculations are equal to 0.

Can someone give a hand?

QED.mw

Thanks a lot.

Hi

I have the following functional

I was wondering how I would evaluate the following in Maple

Thanks

James

Hi....how can i multiply the 9*4 matrix on the left side of this table to the 9*1 vector on the right side of it (last column) with a kind of product of cells that results a 9*4 matrix made up of cells like this one's [(a,b,c,d)⊗(e,f,g,h)=(ae,bf,cg,dh)]

can anyone help me please?

Hye, have a good day everyone..

can anyone know why I got this error? :(second_grade.mw

Error, (in dsolve/numeric/bvp/convertsys) unable to convert to an explicit first-order system

Here I have attached the file. thank you in advance :)

Why can't I run a produce on the Maple IDE? I can't add Maple environment to Maple IDE. The error is this.

License expires in 29 days
|\^/| Maple 18 (X86 64 WINDOWS)
._|\| |/|_. Copyright (c) Maplesoft, a division of Waterloo Maple Inc. 2014
\ MAPLE / All rights reserved. Maple is a trademark of
<____ ____> Waterloo Maple Inc.
| Type ? for help.
Error: EnvUtils:-KernelSummary("could not validate license %1, required by %2. Please check the Install.html file under the toolbox directory for instructions on how to activate a license.\nLicense manager error: %3")
memory used=0.7MB, alloc=8.3MB, time=0.11

what means the command that `linsolve` and 

when

a:=matrix([[a1,a2],[b1,b2]])

b:=vector([c1,c2])

c:=transpose(a)

linsolve(c&*a,c&*b)

&* <<--- what is it

I need to make a lot of similar calculations and wonder if it can be done in a smart way in Maple. Microsoft Excel is perfect for this kind of calculations, because you can downcopy cells. I would like to do everything in Maple, if possible, though. I have a number of points A, B, C, D, E, ... , which all lie on various circles in the plane. For every point radius and angle is given, so actually you can say that every point is delivered with polar coordinates. I want to have their rectangular coordinates. 

Maybe I could deliver their radii in a list and their angles in degrees in another list?

r:=[12,56,29,...., 78]:

v:=[15,45,75,..., 102]: 

......

I need to be able to refer to a certain point thorugh an index. At best it would be A, B, C, ... , but 1, 2, 3, ... will be acceptable. So in the end I need to be able to access say x_C and y_C or x_3 and y_3 (understood as index lowered). I hope someone can help me do the task in a nice a efefctive way.

NB! Maybe you have a solution, which involve transformation from polar to rectangular coordinates. That will be nice, but please also tell me how it can be done from scratch, because I want to be able to know about handling many points at once for other purposes, when the function is not r*cos(v), but an arbitrary function.

Regards,

Erik

Is there any some kind of environment variable(or command,package, anything...) that I can play with to tell maple consider all the constrants implied by the given expression

For Example, I want to simplify the following equation(this equation's final form is "0=0" if you take the implied constraints into account.)

 "(4*a^3*b)^(1/2)/(-(a/(4*b))^(1/2))+(4*a^3*b*(4*b/a))^(1/2) = 0" 

in real domain and this equation implies that variable a and b are both negative or positive because of the sqrt operation. And neither a nor b should be zero because they are part of a fraction's denominator.

but if i simply tell maple to simplify this equation, all the constrants will be ignored by maple, even if i use RealDomain package.

My problem is the following; Let's say that I want to make a simple program of designing of a steel beam. In order to do so, there is a respectable number of parameters that have to be taken into account - forces, geometrical characteristics etc -. So for example, I have an excel file that has the following rows

1) A row of variables  :                          LENGTH   MOMENT_OF_INERTIA   AXIAL_FORCE    HEIGHT_OF_SECTION
 
2)A row of a value for each one variable :      5                556                       130                       300


the traditional approach in maple to intoduce these values to the program would be:

LENGTH:=5
MOMENT_OF_INERTIA:=556
AXIAL_FORCE:=130                etc etc

and then when for example we write

MOMENT_OF_INERTIA/LENGTH       we get

556/5=111.2

..but for problems like this the variables may be 50 in number, even more.. and it would be very timeconsuming to define all these parameters one by one..
so what I have been looking for so much these days is a predefined maple procedure - if there is one.. - that takes a matrix which we have created in advance and that includes all the names of the variables that we want to have in the problem - let's name it VARIABLES - takes as well a matrix that we also have created in advance and includes the value that we want each of our variables to get in the problem - let's name it VALUES - and make the correspondense automatically, so as to when we introduce an epression in maple thereafter, like     MOMENT_OF_INERTIA/LENGTH, when we press enter to get  556/5=111.2  (and not just a reproducing of what we already wrote , MOMENT_OF_INERTIA/LENGTH ..).. Do you think that there is an easy way to do so??

many thanks in advance!