evalhf.mw

## A possible bug in Maple 2019: a strange problem of...

Hello everyone, Greetings!

I am facing a really strange problem. I need to write an expression, however, maple out of nowhere assigns values to the variable used. only to those which are written inside sin (). In previous versions the out put is fine. Is there a new way to write expressions in maple 2019? I am not sure.

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 > 96*sin(2*beta*y)*cos(2*beta*y)*beta^4 + 96*sin(2*beta*y)*beta^4
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## How do I remove this message? ... Generate by lo...

I get the following when MAPLE starts...

Warning, .hdb help databases are deprecated, 'C:\Program Files\Maple 2018\lib\OrthogonalExpansions.hdb' will not be used, see ?HelpTools,Migrate help page for more information

I have recently loaded an orthogonal expansions package created for earlier versions of MAPLE.

How can I remove the message?

MRB

## Laplace inverse?...

Hello,

How I can take Laplace inverse?

Thank you

LAPLACE

Maple Worksheet - Error

Failed to load the worksheet //convert/LAPLACE

## How isolate based only in the second index?...

Hi, im working on integration methods and i would like to make a routine that put to left side from a equation only the terms that have 'j+1'. So for example, we have the heat-conduction equation and we want to develope a approximated solution by an implicit method, so:

at this point i have tryed different ways in order to select only the terms that T [any,j+1], because we want T[i,j+1],T[i+1,j+1] and T[i-1,j+1] to the lhs of the equation and the rest to the rhs

I would like to make Maple read only the second index as a criteria to select or not.

Someone have any idea on how to make maple deal with it?

## How to automatically cancel any common factors on ...

I have encountered the situation frequently where I want to simplify an equation by cancelling out terms on both sides.  I have tried simplify() with a variety of assumptions(J,L>0,etc) and I haven't been able to get it to work.  On a simple equation, one can use 'solve' however there are situations where solve doesn't work and I just want to simplify the equation not solve it.

The script below shows the situation.  I cancel out JL and the complex exponential by manually identifying that they are common factors.  Is there an automatic way of doing this type of simplification?

If I use expand() it clearly shows the common factors on both sides but I haven't found the command that removes any common terms.

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## Series Expansion at Infinity with multi-variable...

How can I expand the series in multi-variable, where all variable tends to infinity.

Suppose I have a function F(x,y,z) and I want the series of F in all three variable at {x=Infinity, y=infinity, z=infinity}

## MAPLE and multidimensional Fourier Transforms : i....

Does MAPLE have capabability to do multidimensional FTs i.e. (x,y)->(u,v)? If not, are there any links to MAPLE packages which meet this requirement that can be recommended?

Melvin Brown

## thread makes computational time more...

I used thread for a loop and found that it takes more time than evalf. Please help to decrease the computational cost. Thank you.

## To Obtain the Column Rank of a Matrix Over Finite ...

Consider the finite field G:=GF(p,k) for some prime p and a positive integer k. Let H be an nxm matrix over G.

My question: How to obtain the minimum number of linearly dependent columns of the H over G.

## Solving symbolically matrix equations ...

-Can we solve symbolically matrix equations where the matrices are ungiven by MAPLE?

For a simple example;

Let A.B+2B=C.

where A nxn is matrix and B, C and nx1 matrices. (all matrices are ungiven)

Question: Find symbolically matrix B in terms of C and A?

My try:

We can quickly calculate Matrix B by hand.  We have (A+2I)B=C and so B=(A+2I)^(-1).C   ( where (A+2I) is invertible and I is nxn identity matrix)

Briefly: Can we do for the more complex and difficult equations by MAPLE?

## How apply typesetting for variables that depend of...

Hello, i wish to get dot displayed for time derivative and prime displayed for space derivative. I put typesetting in extended mode but it seems to only work for variable that depend only of time. So how can i get (in 2D math) dot displayed for derivative in time and prime displayed for space?

Example u(x,t):

diff(u(x,t),x) --->  u'(x,t) output displayed in prime

diff(u(x,t),t)  --->  u^. (x,t) output displayed in dot

Thanks

## how to solve this simplification problem?...

hi guys i have a question for you,

can anyone help me to find the correct code to mantain the structure of vel_qD list and simplify the term diff(s1(t),t)??

i'm driving crazy for that beacuse i'm not able to do it...

thanks, down here i post the code...

## Showing Weyl tensor is equal to zero in 3D...

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Weyl tensor is identically equal to zero in 3D and I have tried to show this by inputting an arbitrary metric and calculating components of Weyl tensor. Thus this answer should give me the empty set but I am not getting that, thanks in advance.

CODE:

with(Physics):

Setup(mathematicalnotation = true)

Setup(dimension = 3, coordinates = (X = [x1, x2, x3]), metric = 2*F6(X)*dx2*dx3+2*F5(X)*dx1*dx3+2*F4(X)*dx1*dx2+F1(X)*(dx1^2)+F2(X)*(dx2^2)+F3(X)*(dx3^2))

g_[]

Weyl[alpha, beta, mu, nu, nonzero]