Why does Maple 2015 solve this very simple system incorrectly?

solve({abs(a-b)=0, sqrt(2*b+c)=0, c^2-c+1/4=0});

With Maple 12 no problem:

solve({abs(a-b)=0, sqrt(2*b+c)=0, c^2-c+1/4=0});

Hi,

I try to solve a system of two second order non linear ordinary differential equations using Maple that I expect to find singularities as blow-up points.

So, I would like to know how to compute values of singular points when existing.

Thank you in advance. 

ode1: -0.1*diff(u(z),z$2)+(z-2*diff(v(z)^-1/2,z))*diff(u(z),z)+(3-2*diff(v(z)^-1/2,z$2)*u(z)=0

ode2: 0.1*diff(v(z),z$2)+0.01*z*diff(v(z),z)+0.02*v(z)-u(z)*v(z)^1/2=0

Ics: u(0)=0, v(0)=0, D(u)(0)=0, D(v)(0)=0

Hi

I have problem with 3Dplotting of this piecewise...can anyone help me please?!

since i know the output will be a value between 0 and 1 can i plot it for different values of Mu in this range to eliminate a dimension?

Mu(x1, x2, x3) = piecewise(`or`(`or`(x1 > 55, x2 > 10), y >= 2), 1, x1 < 35 and x2 <= 10 and x3 < 1, (1/10)*x2, `and`(`and`(x1 < 35 and x2 <= 10, x3 >= 1), x3 <= 2), max((1/10)*x2, x3-1), `and`(`and`(`and`(x1 >= 35, x1 <= 55), x2 <= 10), x3 <= 1), 1-((55-x1)*(1/20))((10-x2)*(1/10)), `and`(`and`(`and`(`and`(x1 >= 35, x1 <= 55), x2 <= 10), x3 >= 1), x3 <= 2), max(x3-1, 1-((55-x1)*(1/20))((10-x2)*(1/10))))

Thank you very much in advance...

restart;
#plot(exp('frem'(x+1,3)-1),x=-5..5,discont);
int(exp('frem'(x+1,3)-1),x=-5..5);
Error, (in int) wrong number (or type) of arguments: invalid options or option values passed to exact integration
evalf(Int(exp('frem'(x+1,3)-1),x=-5..5));
Error, (in evalf/int) when calling 'frem'. Received: 'invalid input: frem received x+1, which is not valid for its 1st argument, x'
sol1:=dsolve({diff(x(t), t)=eval(piecewise(0 <= t and t < 10/3, 60, 10/3 <= t and t < 13/3, 0),t='frem'(t,13/3)),x(0)=0},numeric,output=listprocedure);
sol2:=dsolve({diff(y(t),t)=eval(piecewise(0 <= t and t < 4, 50, 4 <= t and t < 5, 0),t='frem'(t,5)),y(0)=0},numeric,output=listprocedure);
#two commands above are well,but the below is not well.
sol:=dsolve({diff(x(t), t)=eval(piecewise(0 <= t and t < 10/3, 60, 10/3 <= t and t < 13/3, 0),t='frem'(t,13/3)),diff(y(t),t)=eval(piecewise(0 <= t and t < 4, 50, 4 <= t and t < 5, 0),t='frem'(t,5)),x(0)=0,y(0)=0},numeric,output=listprocedure);
Error, (in signum) invalid input: frem received t, which is not valid for its 1st argument, x
plots:-odeplot(sol,[[t,x(t)],[t,y(t),color=blue]],t=0..50,gridlines=true,thickness=2);
Error, (in plots/odeplot) input is not a valid dsolve/numeric solution.

any advice is appreciated.

Maple show "

Error, (in simplify/hypergeom/baseHG) Maple was unable to allocate enough memory to complete this computation. Please see ?alloc"

after I finish the equations set and run it.

what's the reason?

hi,

 I solved  the laplace equation(pde) in spherical cordinates(in my problem tempreture is steady and azimuthal(theta) asymmetry,so my data is a simple function of "phi".)

but I'm really confused,how to make a contour plot of this data on the surface of the sphere where only each point of (phi)axis has a corresponding data value> "simplify(u(1,phi))"?? [the code with the data "u" is attached]

plzz help me soon and abit simple for a newbie,tnX alot. 

Download ques.mwques.mw

I am new to maple and I need help.

Let x=x(t) and y=y(t) be functions in t. Suppose that x'=2x−5y+t and y'=4x+9y+sint such that x(0)=y(0)=0. Find y(1).

How do I go about doing this question?

Thanks

Can I use Maple to solve equation like  for a,b,c?

a,b,c are real numbers and I need to solve it in real domain.

With this application we can meet safety characteristics of a relationship and simple or compound functions. Made with maple 2015.

Relaciones_y_Funciones.mw

(in spanish)

L.AraujoC.

Dear all,

I have one probem in using Maple in comparison with Matlab.

Generally, when using Matlab, I write a long program with 500 lines (for example) and where I use some matricial calculations and other. When I want to repeat this program for some parameters (variables) many times, I transform the program to a procedure "Function" with just adding the command Function in the start of the program.

When using Maple, I have a difficulty to transform a long program which I want to repeat for some variables to a procedure "proc". The program uses packages like LinearAlgebra and other procedures.

Is there a simple way to transform a long Maple program to a procedure which should be repeated many times for some variables in Maple. 

I have especially problems with the commands local, global, use (for packages), etc.. and the warning related to the variables. It is not easy for a long program with many variables to write them in local or global variables.

Thank you.

I find mapleform software   but I dont know how to use , and does anyone know another method to convert.  I know use 

> with(MmaTranslator);
> MmaToMaple();  

I can  automatically translated .nb files.  but this have  

Error, (in readline) file or directory does not exist
Error, (in readline) file or directory does not exist
Error, (in readline) file or directory does not exist
Error, (in readline) file or directory does not exist

another Error, missing operator or `;`

also I try to use 

> with(MmaTranslator);
> FromMmaNotebook(Mma_notebook_filename, options);

I still dont know how is works?  can you explains for me and show me some example  , here is my example files.plot.zip

Hello everyone!

I'm trying to understand how to work with PDEs in Maple by solving a basic PDE such as the wave equation, along with conditions at t = 0 in terms of arbitrary functions. I stumbled upon the very same example, included in the Maple Online help at this page under the part "Three Textbook Examples":

I tried to copy and paste the code and execute it, but to no avail: it seems like pdsolve doesn't give me any other result than a blank space, unlike in the example reported in the Online help. Can anyone tell me if (and where) I am doing wrong? Is it possible that my version of Maple (Maple 13) may not be compatible with the procedures required by this example?

 A warm thank you to whoever will help me!

Hi EveryOne!

In the the answer of the question "How to find roót of polynomial in finite field and extension finite field (at URL: http://www.mapleprimes.com/questions/203977-How-To-Find-Roots-Of-Polynomial-In-Finite#answer215097). Carl Love helped compute eigenvalues (x_1,x₂,...,x_n)and eigenvectors of the given matrix M over GF(2⁸)/(y^8+y^4+y^3+y+1).

I need to do:

1. Get matrix D from these eigenvalues (x_1,x₂,...,x_n), with D[i,i] = x_i and D[i,j≠i] = 0 (D will be diagonalizable matrix. Some x_i may be in extension finite field  GF((2⁸)²))

2. Get matrix P from eigenvectors corresponding to the above eigenvalues, compute P^-1

3. Compute matrix B = P x D^1/4 x P^-1 in  extension finite field  GF((2⁸)²).

Please help me!!! 

During a lengthy computation of mine - done using a well established and scientifically sensible external package - I get a Too many level of recursion error in PDEtools/NumerDenom.

Since it has always worked fine for simpler computation with the exact same code, I am wondering whether, with a bigger bound of the level of recursion, the computation could be succesful.

Which is the max level of recursion than maple allows?

Is it possibile to manually (at one's own risk) raise it, in the same line as raising, for instance, stacklimits kernel option?

I am doing some lengthy computation using the externally developed (and published in academic journals) package 'Janet' to compute the compatibility conditions of an overdetermined set of linear PDEs.

At some point in the process (for a set of equations rather, but not SO, complicated) the procedure gives the error

in (PDEtools/NumerDenom) too many level of recursion

I have contacted the developer of the packages and he told me that he never directly calls PDEtools functions, so he deems that that call is made by some more standard maple command (such as simplify).

I could not find any documentation of NumerDenom function, to try and understand what might be the problem (my set of equations has some extremely 'bad' fractions, but I hope this is not that naive)

How does NumerDenom works, and where is it called by 'standard' maple command?

Thank you all.