******************************************where d1 to d45 -kappa and chi are constant**********

dsys4 := {d1*h1(theta)+d2*(diff(h1(theta), theta, theta))+d3*(diff(h2(theta), theta))+d4*(diff(h2(theta), theta, theta, theta))+d5*h3(theta)+d6*(diff(h3(theta), theta, theta))+d7*(diff(h1(theta), theta, theta, theta, theta)) = 0, d8*h2(theta)+d9*(diff(h2(theta), theta, theta, theta, theta))+d10*(diff(h2(theta), theta, theta))+d11*(diff(h1(theta), theta))+d12*(diff(h1(theta), theta, theta, theta))+d13*(diff(h3(theta), theta))+d14*(diff(h3(theta), theta, theta, theta)) = 0, h3(theta)^5*(d16+ln(h3(theta))^2*d15+2*ln(h3(theta))*d17)+(diff(h3(theta), theta, theta))*h3(theta)^4*(d19+ln(h3(theta))^2*d18+2*ln(h3(theta))*d20)+(diff(h3(theta), theta, theta, theta, theta))*h3(theta)^4*(d22+ln(h3(theta))^2*d21+2*ln(h3(theta))*d23)+h1(theta)*h3(theta)^4*(d25+ln(h3(theta))^2*d24+2*ln(h3(theta))*d26)+(diff(h1(theta), theta, theta))*h3(theta)^4*(d28+ln(h3(theta))^2*d27+2*ln(h3(theta))*d29)+(diff(h2(theta), theta))*h3(theta)^4*(d31+ln(h3(theta))^2*d30+2*ln(h3(theta))*d32)+(diff(h2(theta), theta, theta, theta))*h3(theta)^4*(d34+ln(h3(theta))^2*d33+2*ln(h3(theta))*d35)+h3(theta)^4*(d37+ln(h3(theta))^2*d36+2*ln(h3(theta))*d38)+h3(theta)^4*(diff(h2(theta), theta, theta, theta, theta, theta, theta))*(d40+ln(h3(theta))^2*d39+2*ln(h3(theta))*d41)-beta*h3(theta)^3*d42-chi*ln(h3(theta))^2*d43/kappa-chi*d45/kappa-2*chi*ln(h3(theta))*d44/kappa = 0, h1(0) = 0, h1(1) = 0, h2(0) = 0, h2(1) = 0, h3(0) = 1, h3(1) = 1, ((D@@1)(h1))(0) = 0, ((D@@1)(h1))(1) = 0, ((D@@1)(h2))(0) = 0, ((D@@1)(h2))(1) = 0, ((D@@1)(h3))(0) = 0, ((D@@1)(h3))(1) = 0, ((D@@2)(h3))(0) = 0, ((D@@2)(h3))(1) = 0}; dsol6 := dsolve(dsys4, 'maxmesh' = 600, numeric, output = listprocedure)

hi

DirectSearch answer has confused me. How to reduce the residual.
See the program.Direct.mw

Hi,

I would like a plot of the solution of this differential equation : diff(phi(x),x,x)=phi(x)*(Ep(x)-E) with for example Ep(x)=(1-exp-(x-2))^2 and E=0.5

So :

>restart;with(plots); xith(DEtools);

>Ep:=x->(1-exp-(x-2))^2;E:=0.5;

>sol:=dsolve({eq,phi(o)=0,D(phi)(0)=0},type=numeric,range=0..10);

>odeplot(sol);

but nothing appear in the plot except axes

Thanks for answer

Hi,

I want to solve two equations which I am mention in worksheet, i want the answers except complex values, when I am trying to solve in maple 18 it take too much time to evaluate, and also I did not get the answer, give some suggestions and ideas to do solve that work .
two_equations.mw


Thankyou...

Hi everyone,

I have a maple program that generates a polynomial g(y)=(80y^8 + 68y^6 + 12y^4 -4y^2 -1). This polynomial has two real roots (irrational roots), call them +/- y*. My code does a sequential calculation, and often sI am left with a higher order polynomial in y that has the form h(y)= p(y)*g(y), where p(y) is also a polynomial in y. This polynomial h(y)=p(y)*g(y) is not in factored form (i.e. it would look like expand(p(y)*g(y)). Is there a way to instruct maple to recoginize that +/-y* is also a root h(y)=p(y)*g(y)? So far I've tried things like applyrule([g(y*)=0],h(y*)), but nothing seems to work (I suspect because Maple cannot recgonize that g(y) is a factor of h(y)). I am not interested in computing this numerically. I am just trying to find a way to instruct Maple to recognize symbolically that h(y*) =0.

Thanks a million for anyone who has any idea.

Best,

Justin

Hi Maple users :)

do you know if exists a Maple package in order to perform a Panel method, for instance in the Hess-Smith version, for solving incompressible potential flow over thick 2d and 3d airfoil geometries?

Thank in advance for the help.

solve Differential equation "a-y=y' bc" use maple 17

the result is y(x)=a+_C1e^-(1/bc)

but the correct result  isn't y(x)=a-_C1e^-(1/bc) ?

Thank you in advance for your help

Hi :)

I have a Macbook Air running on OS X Mavericks. I am using Maple16.

I created a procedure, which construct two keys. Each of those keys consists of a list containing two elements. That is two primes. So at the end of my procedure I included the following code in order to write my data to a file:

> pkey := fopen(keyFile, WRITE, TEXT);
                      pkey:=1
> writedata(pkey, publicKey);
> fclose(pkey);

The problem is that I can't find the created file "keyFile".

So I tried breaking the problem down. I created a List and wanted to write that list in a textfile in a specific folder:

> L := [1, 2, 3];
> fd := fopen("Users\\****\\Desktop\\fdtest.txt", WRITE, TEXT);
                              fd:=1
> fprintf(fd, "This is a test");
                              14
> fclose(fd);

But this did not work either. It seems like the file fdtest.txt never gets created. This happens in general when I use fopen().

Thank you in advance for your help

Schloemilch

I have a matrix then I need to plot its columns as curves on one plot.

I'm interested in doing some experimental mathematics using the PSLQ integer relation algorithm.  The only third-party program for doing PSLQ problems I've been able to find is a GNU C++ program with a less-than-user-friendly command-line interface.  I've heard that Maple implements PSLQ and I like the symbolic input and presentation it offers as a CAS, but I can't find any information on which alternative types of Maple 18 make the PSLQ algorithm available.

I am trying to plot several curves with values from matrix columns on one plot.

L1 := zip(`[]`, groups, waitArray[ .. , 1]);

L2 := zip(`[]`, groups, waitArray[ .. , 2]);

plot([L1, L2])

plot(L1) and plot(L2) work fine.

But for a joined plot I have an error

Error, (in plot) incorrect first argument [Array(1..3, {(1) = [5, HFloat(0.2889190508261187)], (2) = [10, HFloat(0.9017773091123074)], (3) = [20, HFloat(2.4000000155705576)]}), Array(1..3, {(1) = [5, HFloat(0.019538366928174924)], (2) = [10, HFloat(0.06875266075705706)], (3) = [20, HFloat(0.1884304855100058)]})]

f1 := expand((a1*x^2+b1*x+c1)^n);
f2 := a1*x^2+b1*x+c1;

solve([coeff(f1, x, 4) = coeff(f2, x, 4),
coeff(f1, x, 3) = coeff(f2, x, 3),
coeff(f1, x, 2) = coeff(f2, x, 2),
coeff(f1, x, 1) = coeff(f2, x, 1),
coeff(f1, x, 0) = coeff(f2, x, 0)], [a1,b1,c1,d1]);

hi,

i cant solve this 

int(1/1-exp(a*x)*erfc(a*x))

restart;

Vector([a, b]);  <a, b>;  # Identical results

a:=[1, 2]:  b:=[3, 4]:

Vector([a, b]), <a, b>;   # Different results. Why?

I have a vector of lists, and each list is composed of indexed names.  For each list, I would like to assign all the indexed names in the list to the first variable of the list.  Right now, I'm trying to select the entries of the list using the op command and then assign one to the other, and get the following error:

Error, invalid left hand side in assignment

June_29.mw

Thanks!