Dear Community,

Would someone have a good and easy to understand/implement description of the Den Iseger algorithm for the numerical inversion of Laplace transform? Even better if someone would have a Maple script to do it, that would be superb.

Tx in advance,

best regards

Andras

Hello guys

I am trying to solve a non-linear 2nd order diffential equation in order to describe the turbulence phenomena for tip vortices .

The initial conditions that i have are

b(0)=1

b(8)=exp(.1842068074*ln(-(2.*(-1.+b(x)))/(2.*b(8)-7.))+9.670857391)

Moreover i know that b from 0 to 1 equals one and then it  increases propably parabololoid(from the experimntal measurements)with respect o Re(Reynolds)

I tried to solve the eqution using maple solve de interactivelly but doesnt seem to work

Do you have any suggestions?

Thank you

giorgio_3.mw

I updated the OSX from El Capitan 10.11 to Sierra 10.12.

After then, whenever I try to input Japanese characters, Internal Error notification appears, and it crashes.
As it is not realistic to go back to the old OS, as the time when I did back up was a little before, I wouldn't do so.
Then, I might end up torelating not using Japanese until the next version of maple appears next year.
Are the situations like this ?

I know there might not be any response as this is about inputting Japanese characters.

Best wishes.

taro

Hello

I am trying to solve interactively the following DE with initial condiotion b(0)=1 and maple freezes as well as my pc.Can you help me?

Hello, 

I have a PDE system. When I use pdsolve it gets me the messege " pdsolve->Warning: System is inconsistent". Is there a way I can see which equations breaks the system down? 
For this system, it's difficult to see from ayeball where the problem is. 
Thank you! 

test.mw

When I use the Determinant function on a matrix with (single variable) polynomial entries with real coefficients I often get an incorrect answer. I know the answers are incorrect because they have a higher degree or a lower lowest degree than is possible given the matrix elements.

However, when I replace the coefficients in the polynomials with rational numbers or I put in the option method=minor, I get the correct answer.

The problem seems to be roundoff error. However, the important error is not simply small changes in the resulting polynomial. The important error is the presence of entirely incorrect powers of the variable and not with very small coefficients.

How does this happen and why does the help page for Determinant( ) not warn of this behavior? In particuiar, why does the help page not say that using Gaussian elimination (i.e., the default) will often give incorrect answers in such cases, but using method=minor will work? Is this behavior known? I cannot find any reference to it on the internet.

Hello all. Is there any solution for the indefinite integralBadIntegral.mw

Download BadIntegral.mw

?

Thanks

i copy maple code from notepad to maple in maple window,

there is no error

my function in the code

explicit define parameters are Local type

for example

appendto("...");

func1(aaa)

Local aaa;

but when i run cmaple to read the code text file in window 8

it return error

missing operator, syntax error

at Local aaa;

originally 

i have defined

Local aaa, ii;

for ii from 1 to nops(aaa) do

etc.

but it has error too,

then i change to one by one

Local aaa;

Local ii;

still have error at Local aaa;

if i m working in maple 13 i have to solve a non linear integral equation then what will be the steps to use the do loop.

Hello all,

Is here anyone who could help me with this Integral.

I want to determine P(y=2) in which the Nu is a constant and also is unknown.

In deed I want to derive the P which only has one unknown parameter(Nu). But I cannot solve this indefinite integral although the \alpha_1 , \alpha_2 and B are known constants. The Nu parameter mustn't be valued preferely.Indefinite_INtegral.mw

Here is my code. I am deriving soil compression line for oedometric testing with porosity, below is a part of the derivation.

I would like to differentiate the (Sst/Vst)/(Spt/Vpt) by dsm first then integrate it with dsm ranges from 0 to dmax to get my final answer...

Hope someone can help me on writing the code... Thank you very much!!!

Download GEO_Assignment_3.mw

n := 5:
z1 := exp(2*3.14*I*k1/n)*cosh(z)^(2/n);
z2 := exp(2*3.14*I*k2/n)*sinh(z)^(2/n);
xx := Re(z1);
yy := Re(z2);
uu := cos(alpha)*Im(z1) + sin(alpha)*Im(z2);

i find that the 3d graph has many intersection points to itself

how to find these intersection points of calabi yau ?

Dear readers,

For a question for my students I want them to calculate tge resulting vector from two vectors. The student had to answer by giving the length and angle of the resulting vector.

For the question the vector angle is always larger as 180 derges, the student should for example give a result of 270 degrees.

Currently I'm using the following code:

$F1=100;#range(200,500,20);
$F2=100;#range(100,200,10);
$A1=45;#range(10,80,5);
$A2=45;#range(10,80,5);
$A1r=180+$A1;
$A2r=360-$A2;
$F1x=maple("cos(($A1r)*Pi/180)*$F1");
$F1y=maple("sin(($A1r)*Pi/180)*$F1");
$F2x=maple("cos(($A2r)*Pi/180)*$F2");
$F2y=maple("sin(($A2r)*Pi/180)*$F2");
$V1=maple("Vector(2,[($F1x),($F1y)])");
$V2=maple("Vector(2,[($F2x),($F2y)])");
$V3=maple("($V1)+($V2)");
$F3=maple("LinearAlgebra[Norm]($V3)");
$V0x=maple("Vector(2,[1,0])");
$A3=maple("LinearAlgebra[VectorAngle](($V0x),($V3))");
$A4=maple("evalf((($A3)*180/(Pi)))");

As you can see maple will always give an angle smaller than 180 degrees since the angle between two vectors is always 180 degrees or smaller.

Can anyone tell me how I should code this problem such that the rest for A4 will be 270 degrees rather than 90 degrees, as is given from the current way of coding.

Thank you in advance.