Hi, 

I'm being unable to plot the solution to the equation

schro := {-(diff(psi(x), x, x))+(2*a*b*x^4+a^2*x^6+(b^2-a*(2*p+3))*x^2-(2*p+1)*b)*psi(x) = 0};

for the special cases of a=b=1 and p=0 and p=1

I've used dsolve and am getting Heun functions :-(

The claim is that the solutions come out to be exponentials of the form:

psi(x)=(x^p)*exp(-(a*(x^4))/4 - (b*(x^2))/2)

thanks in advance

I am trying to implement Subresultant p.r.s. algorithm for calculating greatest common divisor. The algorithm decribed in the book:

My code return the correct GCD, however the sub-resultant terms are different from the result of the built-in function. The last term a[i-1] is huge and involves fractions. I think my implementation is same as the algorithm described in the textbook.

I have attached the file. Could anybody spot anything wrong in the code? Why do fractions still appear? In my code, "lsr" is last subresultant term returned from the built-in function, the second one is my result.

Download subresultant.mw

I am having difficulty to solve the following ODE

ode:=diff(R(x),x$6)=Dirac(x-y);

with initial and boundary conditions

bcs := ((D@@3)(R))(1) = 0, R(0)-((D@@5)(R))(0) = 0, ((D@@2)(R))(0)-((D@@3)(R))(0) = 0, ((D@@5)(R))(1) = 0, (D(R))(0)+((D@@4)(R))(0) = 0, ((D@@4)(R))(1) = 0;

I want to solve the above ODE for two cases 1) x>y and 2) x<=y

Thanks

Let us consider 

MmaTranslator:-FromMma(" Table[0,{n=10},{m=2}]");

[seq([seq(0,i=1..(m := 2))],j=1..(n := 10))]

The above result is syntactically incorrect in Maple language. The translation should be 

Matrix(10,2)
#or
[seq([seq(0,i=1.. 2)],j=1..10)]

up to the Mmma's result

Table[0, {n = 10}, {m = 2}]

{{0, 0}, {0, 0}, {0, 0}, {0, 0}, {0, 0}, {0, 0}, {0, 0}, {0, 0}, {0,0}, {0, 0}}

Another bug is as follows.

MmaTranslator:-FromMma("Sinc[x]");

Sinc(x)

whereas the expected result is piecewise(x=0,1,sin(x)/x) up to http://reference.wolfram.com/language/ref/Sinc.html

In general, the MmaTranslator package is outdated. It often returns working Mma's commands as incorrect (Concrete examples are long and need a context. These may be exposed on demand.). The question arises about the quality of other Maple translations. 

Hello,

I want plot this equations with values independents x,A,B

But this is error.

Any idea?

Thanks

I resolved the coefficients to a 2nd order diff eq of the form:ay''+by'+cy=f(t)

I have included the .mw file for convenience at the link at the bottom of the page.  I resolved the coefficients in 2 different ways & they do not concur.  The 1st approach used the LaPlace transform & partial fraction decomposition.  The coefficient results are given by equations # 14 & 15.  The 2nd approach used undetermined coefficients where I assumed the particular solution and then applied the initial conditions to resolve the coefficients pertaining to the homogeneous solution which are given in the results listed in equation #23.  Noted in the 1st case the coeff's are A₃ & A₄ and for the 2nd approach the coeff's are A₁ & A₂.  I have worked this numerous times & do not understand why they do not concur.  So I thought I should get some fresh eyes on the problem to find where I may have gone wrong.

Any new perspective will be greatly apprecieated.

I had trouble uploading the .mw file so I have included an alternative link to retrieve the file if the code contents is illegible or you cannot dowlad the file drectly from the weblink  Download coeffs_of_homogen_soln_discrepancy.mw.  You should be able to download from the alternative link below once you paste the link into your browser.  If you cannot & wish for me to provide the file in some other fashion respond with some specific instructions & I will attempt to get the file to you.

https://unl.box.com/s/dywe90wwpy0t4ilkuxshkivz2z26mud8

Thanks 4 any help you can provide.

Download coeffs_of_homogen_soln_discrepancy.mw

I need to implement gaussian elimination with cross multiply. I followed the method decribed in the textbook, however the result returned a wrong determinant. I noticed that cross multiplication changes the determinant in every step. Does anybody know how to use the cross multiplication without altering the determinant?

Find the first 6 non-zero terms of MacLaurin series of the function erf(x)

Consider the expression ∑_n=1 (-1)ⁿ e^*n/n²

1. Find the symbolic value of this sum.

2. Find an approximation for the value when  = -2.

3. Build a function to calculate an approximation for the value of the given expression for

any value for 

Hi all, first poster just getting to grips with Maple here. I am having some problems with the 'verify' function in Maple - I can't understand why it is returning 'FAIL' An example of my printout is given below. 

> verify( 2*q/(q^4+q^2+1)-1/((q-1)^2*(q+1)), 0, 'greater_equal') assuming q>7;

                                             true

> verify( (2*q+1)/(q^4+q^2+1)-1/((q-1)^2*(q+1)), 0, 'greater_equal') assuming q>7;

                                             FAIL

Now it's th second line i'm interested in and it was only after trial and error that i found the first option worked. The fact the 1st does but 2nd doesn't makes no sense to me. Perhaps it's something stupid i'm missing - any help would be great. Thanks.

Dear all,

I'm investigating the vibration performance of timber beams. I have sample data from my test which shows the vibration of the beam. I want to determine the eigenfrequency from this data. The problem I face is that I'm not finding the probber eigenfrequency. I have two data rows; time and amplitude. I'm able to plot the amplitude with SignalPlot but not the time, therefore I have to adjust the samplerate. I have the same problem with the fourier analysis. Is it possible to include the time period as well?

Regards,

Maurits

Hello,

I need a bimodal distribution. Since I could not find any among the ones provided by Maple, I created a simple one:

with(Statistics):
U := Distribution(PDF = (proc (t) options operator, arrow; piecewise(t < -5, 0, t < 5, -(1/2000)*t^4+(9/1000)*t^2+7/80, 0) end proc)):
X := RandomVariable(U):

#Plotting PDF and CDF works fine:
plot(PDF(X, t), t = -infinity .. infinity);

plot(CDF(X, t), t = -infinity .. infinity)

However, plotting the quantile function does not work:

plot(Quantile(X, z), z = 0 .. 1);

it has a decreasing part for z<1/2 and a discontinuity at z=1/2.
I can plot it correctly as
plot('Quantile'(X, z), z = 0 .. 1);

but I wonder why the first option does not work for such a simple distribution.

I have a trouble of Maple.
I can't understand the solution of Maple for simplification of Dirac and Heaviside functions.

I wrote the below code,

"restart:
simplify(Dirac(x)*f(x))".

Then, Maple return the answer of this code, "Dirac(x)*f(0)".
I could understand this solution, then I rewrote the next code,

"restart:
_EnvUseHeavisideAsUnitStep:=true:
Heaviside(0)"

Then, Maple returned "1", because I set the value of Heaviside's step function H(x) at x=0.
Finally, I wrote the below code, but there was a problem, I think.

"restart:
_EnvUseHeavisideAsUnitStep:=true:
simplify(Dirac(x)*Heaviside(x))"

The solution of Maple was "0".

According to my first code, I think this solution is Dirac(x)*Heaviside(0), that is, Dirac(x).
I can't understand this result.
Someone help me, please.

The command

plots:-implicitplot(evalc(argument((1+x+I*y)/(1-x-I*y))) <= (1/4)*Pi, x = -5 .. 5, y = -5 .. 5, crossingrefine = 1, gridrefine = 2, rational = true, filled, signchange = true, resolution = 1000);

produces an incorrect result

in view of

evalf(argument((1-4+4*I)/(1+4-4*I)));
                          2.889038378

There is a workaround 

plots:-inequal(evalc(argument((1+x+I*y)/(1-x-I*y))) <= (1/4)*Pi, x = -5 .. 5, y = -5 .. 5);

Dear all,

I need to transforme these equation from time domain to frequency domain with fourier transforms and solve it in frequency domain but i received the flowing error

any helps

thank you !

Code :

Download Fourier_TRAns_MAPLEprime.mwFourier_TRAns_MAPLEprime.mw