MaplePrimes Questions

PDE := diff(u(x, t), t$2) = (1/16)*(diff(u(x, t), x$2))-(1/5)*(diff(u(x, t), t)); IBCs := u(x, 0) = x*(1-(1/2)*x), (D[2](u))(x, 0) = x*(1-(1/2)*x), u(0, t) = 0, (D[1](u))(1, t) = 0; Sol := pdsolve({IBCs, PDE}, HINT = f(x)*g(t)); Sol := subs(op([2, 2, 1], Sol) = n, Sol)

I thought that the addition of HINT wolud help but no.

The numeric solution gives the right answer but the analytical gives way too small numbers and wrong shape.

 

I have a list of coefficients each assigned a triple of indices. E.g. CF_{x,y,z}. These indicies are also able to take other values between +-2. E.g. CF_{x+2,y-1,z} or CF_{x,y-2,z+1} as examples. I have a working loop that cycles through the list of these coefficients and I am able to call a particular one by specifying the triple of indicies. This script has been attached:

triple_index_script.mw

I would like to modify this script to have more control over single indexes. As an example, say I want to add up all the coefficients which have z as a subscript (so not z+1,z-2 etc...) and I don't care what the x and y subscripts are; I want to be able to call that sum using the same notation in the script but with a single index. e.g. (using a new example function called RR_MapZ):

RR_MapZ[0]; ## This would return the sum of all coefficients that had z in their subscript

and this would return the sum of all the coefficients which have subscript Z. If I wanted to add up all the coefficients which had index Z+1 I would do:

RR_MapN[1]; ## This would return the sum of all coefficients that had z+1 in their subscript

What would be the most efficient way to do this?

-Yeti

Is there a command in Maple to produce a table of z values given F(z) where F is the CDF of the Standard Normal Distribution? I know of the command ProbabilityTable to generate a table of z, F(z) values.  What I would really like is F, Inv(F) table of values. I guess  I could write my own code to do this but was wondering if there is an easier way to do this.

How can i convert each column of a matrix(30X10) in a list?

Hi everybody

In the attached file, when I run the code an error appears while calculating "omegaL1" parameter. The dimensions of the matrices are correct but the source of error is unknown to me. Can anyone help me?

Thanks in advance

R2_Link_2D.mw 

a=100 
b=10  

1)c=a-b  
2)d=c*2-k2; k2=(b*2)  
3)e=d*2-k3;k3=k2*2  
4)f=e*2-k4;k4=k3*2  
30) (...)
z=c+d+e+f+(...)
z=?

I need a for Statement that calculates this mathematical sequence.

Thanks

I'm trying to use subs to substitute an unknown variable with a number in a Matrix

My Matrix is called values and I have the following

change := f2:

subs(change = 5, values):

This does nothing but when I have the following, it works as expected (All f2 in the Matrix values are replaced with 5)

subs(f2,values):

I'm wondering if its trying to find and replace 'change'. If this is the case how can I get it to use whats assigned to the variable. (I've tried eval(change) but that doesn't work either)

Many thanks

Hi everybody,

 

Here is a very simple question :
I have two strictly positive reals r and s and the expression
a := r^2 – r*s + s^2
Obviously a is strictly positive too

But I’m not capable to prove this with Maple (2016, Windows 7), even after having declared r and s both positive which, I thought, would have prevent Maple to consider them as potentially complex.
I failed in using "is", "coulditbe", "use RealDomain ..." and so on

Totally distressed I tried to do something simpler ... which ultimately appeared still more upsetting

restart:
assume(r, ‘positive’):
coulditbe(r, ‘complex’) ;    # the answer is (surprising ?) true

I'm probably doing some mistake bigger than I but I don't find it !

Could you be compassionate enough to enlight me !!!

Mammoth thanks in advance

Is there any convenient tool to convert Maple worksheet to Matlab m file, until today?

hello i was wondering is it possible to find the standard error of the coefficents in the NonlinearFit function within the statistical package? or in any other package for that matter?

does someone have angorithme that can find it? 

i've searched around the internet and it does not seem like maple employs this function at all?

hope someone can help:)

HI,

I would like to plot the ODE system in phase transition (3d)

I try this

var:={x1(t),x2(t),x3(t)}:
dsys:={diff(x1(t),t)=x1(t), diff(x2(t),t)=x2(t), diff(x3(t),t)=x3(t)};
   / d                  d                  d               \ 
  { --- x1(t) = x1(t), --- x2(t) = x2(t), --- x3(t) = x3(t) }
   \ dt                 dt                 dt              / 
res:=dsolve(dsys);
  {x1(t) = _C3 exp(t), x2(t) = _C2 exp(t), x3(t) = _C1 exp(t)}
plot3d(res,x1(t)=0..1,x2(t)=0..1,axes=boxed,font=[1,1,18],view=[0..0.6,0..1,-5..0]);

 

This must have a simple answer but I have been unable to figure it out after many attempts. 

I am trying to create a Clifford algebra, and then use the results in the multiplication table "MT". The multiplication table elements are correct as displayed, but I don't know how to access the results in the table (i.e. the products of the basis elements).  For example, trying to access the table results as matrix elements like MT[2,3] doesn't work, presumably because it is not a matrix. In other words, I need a matrix that contains the same information as the multiplication table.

DGsetup([x, y, z], M);
I12 := Matrix([[-1, 0, 0], [0, -1, 0], [0, 0, -1]]);
AD3b := AlgebraLibraryData("Clifford(3)", Cl3Q, quadraticform = I12);
DGsetup(AD3b, '[e0, e1, e2, e3, e12, e13, e23, e123]', '[omega]');
MT := MultiplicationTable(Cl3Q, "AlgebraTable");

 

hello, i have problem here.

> restart;
> with(linalg);
> NULL;
> fungsi1 := sum(d1[h]+b1[h], h = 1 .. 7);
> fungsi2 := sum(sum(d2[h, t]+b2[h, t], t = 1 .. 23), h = 1 .. 7);
> fungsi3 := sum(sum(d3[h, t]+b3[h, t], t = 1 .. 23), h = 1 .. 7);
> fungsi4 := sum(d4[k]+b4[k], k = 1 .. 3);
> fungsi := fungsi1+fungsi2+fungsi3+fungsi4;
> NULL;
> NULL;
> k1 := seq(sum(X[h, t], t = 1 .. 23) >= 9, h = 1 .. 6);
> k2 := seq(sum(Y[h, t], t = 1 .. 23) >= 2, h = 1 .. 6);
> k3 := seq(sum(Z[h, t], t = 1 .. 23) >= 2, h = 1 .. 6);
> NULL;
> k4 := seq(seq(X[h, t]+Y[h, t]+Z[h, t] <= 1, h = 1 .. 6), t = 1 .. 23);
> NULL;
> k5 := seq(seq(Z[h, t]+Z[h+1, t] <= 1, h = 1 .. 6), t = 1 .. 23);
> NULL;
> k6 := seq(sum(X[h, t]+Y[h, t]+Z[h, t], t = 1 .. 23) >= 5, h = 1 .. 7);
> k7 := seq(sum(X[h, t]+Y[h, t]+Z[h, t], t = 1 .. 23) <= 6, h = 1 .. 7);
> NULL;
> k8 := seq(sum(X[h, t], t = 1 .. 23)+b1[h]-d1[h] <= 15, h = 1 .. 6);
> k9 := seq(sum(Y[h, t], t = 1 .. 23)+b1[h]-d1[h] <= 4, h = 1 .. 6);
> k10 := seq(sum(Z[h, t], t = 1 .. 23)+b1[h]-d1[h] <= 4, h = 1 .. 6);
> NULL;
> k11 := seq(seq(Y[h, t]+Y[h+1, t]+b2[h, t]-d2[h, t] <= 1, t = 1 .. 23), h = 1 .. 6);
> NULL;
> k12 := seq(seq(Z[h, t]+Z[h+1, t]+b3[h, t]-d3[h, t] <= 1, t = 1 .. 23), h = 1 .. 6);
> NULL;
> k13 := sum(X[7, t], t = 1 .. 23)+b4[1]-d4[1] = 2;
> k14 := sum(Y[7, t], t = 1 .. 23)+b4[1]-d4[1] = 2;
> k15 := sum(Z[7, t], t = 1 .. 23)+b4[1]-d4[1] = 2;
> with(Optimization);
[ImportMPS, Interactive, LPSolve, LSSolve, Maximize, Minimize, 

  NLPSolve, QPSolve]
> CodeTools:-Usage(LPSolve(fungsi, {k1, k10, k11, k12, k13, k14, k15, k2, k3, k4, k5, k6, k7, k8, k9}, assume = {integer, nonnegative}));
Error, (in Optimization:-LPSolve) no feasible point found for LP subproblem

why it can be? please i need help. 

I have a list of univariate polynomials

P:=[x^2-7*x+10, x^2, x^2+2*x+1]

How do I get the gcd of all of these?

It doesn't like it when I do the following:

igcd(P)

 

Thanks

any idea for my problem?

 

> k1 := sum(X[h, t], t = 1 .. 23) >= 9;
9 <= X[h, 1] + X[h, 2] + X[h, 3] + X[h, 4] + X[h, 5] + X[h, 6]

   + X[h, 7] + X[h, 8] + X[h, 9] + X[h, 10] + X[h, 11] + X[h, 12]

   + X[h, 13] + X[h, 14] + X[h, 15] + X[h, 16] + X[h, 17]

   + X[h, 18] + X[h, 19] + X[h, 20] + X[h, 21] + X[h, 22]

   + X[h, 23], h = 1 .. 6

why 'h' still 'h'. from my textbooks the formula must be like this :
 

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