Hello maple users,

I want to compare 5 functions and see which one gives the best result (highest score). Unfortunatelly, I can't say one function always gives higher results than others. I have 8 variables and it makes the comparison complicated.

I assume 4 of them are constant and the other 4 or not.

c=0.1

p=1

w=0.5

wu=0.8

for Pb= 0:0.025:0.20                   Pb and Pa are probabilities, between 0-20, 0.025 increments
    for Pa= 0:0.025:(Pb-0.025)      ** Pa is always less than Pb
        for Ha= 0:50                      Ha takes values between 0-50
            for Hb= 0:(Ha-1)            ** Hb is always less than Ha

I attached the data file. I appreciate if someone tells me how to compare these functions. Should I put more assumptions to make it easier? Thank you.

data1.mw

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?

Hello,

I would like to kow how I can remove the u2,1 and u3,1 from this matrix. I originally had it as a set of just  u2,1 and u3,1, but I converted it to a list, added the 1, because I needed it as the first value, and then converted it to a matrix. I now want to use the matrix for further calculations, but I dont know how to assign a name to it, and exlude the variable names within it.

I have attached the entire maple sheet, if you need some context. Also, if you see anything else that you think could be neater (I think I did a lot of things in a round-about way, because I haven't really used maple before), please let me know!

Earthquake_2.mw

Thanks in advance!

Raquel

(1) I keep trying to enter a reply, and it just never appears. What's wrong?

(2) How do I get code from the Standard GUI to paste into a reply?

I have recently come across this queastion regarding Z-transforms in maple and am struggling with how to complete the question. Any steps on how to proceed with the folloqwing questions would be greatly appreciated. I have done the first part but cannot fathom where to go with this one.

1. For the difference equation

x[n+2]-(α+β)x[n+1]+α*β*x[n]=n/3^n,  x[0]=a, x[1]=b,

(a) Find the general solution for x[n] in terms of the parameters α,β,a and b

(b)Find the solutions for ithe two cases α=-β and α=β

(c)Examine both solutions found in (b) when α=1, for various values of a and b, choosing values to demonstrate different behaviours of the solutions.

Thanks for reading, any help with steps would be great.

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 :)

Hello!

So as the title says i have a problem with solution of second order differential equation system.

The problem is that after i set some initial conditions and check the solution when the time equals zero, the solution graph is completely different from my initial conditions which is obviously incorrect. I know that i can change "spacestep" parameter, but i am not sure if it is the only way to fix the problem. Are there any other ways to fix this?

Here is a part of my code if it helps

r0=1.570796327
theta0=6.000000000

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.

I need to minimize an Integration

Is there a package or an interactive package management utilities?

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

Thanks guys for your help, I know I am asking sometimes some stupid questions, I spend hours trying to do that, but when I am stock.... I need some help... and when the problem is solved I can see how unintelligent am I .

I want to  get   nonlinear equations solutions using 'solve',but i always meet that the program running long long time,i want to stop this 'solve' procedure giving a limit time.how do i.can you help me.thanks a lot.

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

Link download: maple document