I use Maple 15 to calculate some (nasty) integrals at my university. Because our university also offers a server on which I can run my Maple program, I would like to do that. (instead of occupying a workspace). But at the computer on my workspace the integrals are evaluated fine, but on the server the integrals are just returned with no numerical evaluation.

I constructed a MWE to look where it goes wrong. I set the printlevel to 25 so I could see what was going on. The MWE was suprisingly simple, on both machines (via ssh) I executed within maple:

This of course would normally just give 2*sqrt(2). On my workplace-pc it worked fine and it found 2.828427125. The server just returned the integral. After looking at the steps, they where both exactly the same until the following part:

Workplace-PC:

         General_flags := {_NoNAG, _DEFAULT, _NoMultiple}

            NAG_methods := {_d01ajc, _d01akc, _d01amc}

                        Method := _DEFAULT

                          HFDigits := 15

                                       -12
                        HFeps := 0.1 10

                                            -9
                    HFeps := 0.5000000000 10

   oldEvents := overflow = default, division_by_zero = default

                         callNAG := true

                            fcns := {}

                  result := 2.82842712474618807

Server:

        General_flags := {_NoNAG, _DEFAULT, _NoMultiple}

           NAG_methods := {_d01ajc, _d01akc, _d01amc}

                       Method := _DEFAULT

                         HFDigits := 15

                                      -12
                       HFeps := 0.1 10

                                           -9
                   HFeps := 0.5000000000 10

   oldEvents := overflow = default, division_by_zero = default

                         callNAG := true

                           fcns := {}

       overflow = exception, division_by_zero = exception

It seems that the server has a problem with the singularity and thus throwing an exception, but I just don't get why. The Maple-versions are both the same.

Does somebody know what this could be?

This might be a ridiculous question, but what is the easiest way to check the monotonicity of a function? I didn´t find anything helpful in the Maple Help, so maybe one of you could give me a nudge here :)

the following cmd gives me three 3 solutions: -1, 1,sqrt(2), even if I specificlly assume that a is not equal to neither 1 or -1....

([RealDomain[solve]((1/(a-1)-1/(a+1))*(2*a^2-2)/a = 4/surd(2, 2), useassumptions = true)] assuming a <> 1, a <> -1

why does this wired thing happen?

hi, the equations read as 

eq:=[2*x-0.2e-1*y-2.04*sqrt(-v^2+1)*v, 2*y-0.2e-1*x-2.16*sqrt(-u^2+1)*u, 2*u+2.16*u^2*y/sqrt(-u^2+1)-2.16*sqrt(-u^2+1)*y, 2*v+2.04*v^2*x/sqrt(-v^2+1)-2.04*sqrt(-v^2+1)*x] ;

i do as follows using DirectSearch package v.2

i find the solutions not the same,some time the results not much difference,but another,sols1 have one solution,sols2 have three solutions.in some time,some solutions are lost，the result show  me  random.may i have run the command serveral times? regards.

While I was using DEplot3d, I want to draw a space curve, the equation of which is a list of functions of the vars in DEs. I put them in "scene", but Maple told me this:

Error, (in DEtools/DEplot) Invalid scene; must be list of vars: scene = ...

Now I know that I cannot put functions in "scene", but I am wandering if there are some other way so I can draw this kind of space curve.

Thank you very much!

Hi there,

I am trying to compute the following, and I am getting this error.

> A := map(convert, M, unit_free)*Unit('m'*(1/'s'^2));
(I had to put the Unit('m'*(1/'s'^2)) because the original units were kNm/s^2 (kg), and even though I simplified it, it's still using kNm/s^2, and leaves the m/s^2 for some reason when I try to remove the units. I tried simply changing the units on the original matrix, but the units menu has disappeared from the right-click menu!!)

> B := map(convert, K, unit_free);

Loading RealDomain;

solve;

Error, (in assuming) when calling 'Engine:-Dispatch'. Received: 'should not happen: Rename expects the input to contain unknown functions'

Why is it giving me this error? omega is an unknown variable that I am trying to solve for. I am going a modal analysis, so maybe there is a better way to find omega?

Any help appreciated!

Raquel

I have document Maple.mw. I want to copy all text to mathtype. How do I copy and paste?

Link download: maple document

Why does the following not work?

factors(x^4-1)

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