hi.please see attached file below and help me.thanksode.mw

Download ode.mw

if m:= [01100101, 01101100, 01100111, 01100001];

I want to get [[0,1,1,0,0,1,0,1].[0,1,1,0,1,1,0,0],[0,1,1,0,0,1,1,1],[0,1,1,0,0,0,0,1]];

Any command can solve? Thank you.

hi.please see attached file below and help me.one problem is apply differential operator on matrix and then caclute 3D integral?

maple2.mw

Download maple2.mw

Let A and B two real closed intervals.
I define b(x) as B+x for any real x ; more precisely, if B=[B1, B2], b(x) = [B1+x, B2+x]

I want to build a function f(x) such that :

1. if  A and b(x) do not overlap then f(x) = 0
2. otherwise f(x) is some expression of the covering length

For example : if A=[0, 2] and B=[-2,-1], then

1. f(x) = 0 if  -1+x < 0 or -2+x > 2
2. otherwise f(x) = L   where L is the measure of the intersection of A and b(x)

I coded a few variants using piecewise or Heaviside functions. 
In some sense I have already answered my own question ... but no one is neither elegant nor concise.

I wonder if there exist a Maple function that returns the measure of the intersection of two real intervals (when they overlap) and 0 otherwise ?

Hi,

I have been trying to solve the following equation with respect to y, but I have not been successful. In fact, I always get answer RootOf(...). I should mention that all variables and parameters are real non-negative. I have also tested with "assume", but it did not help. Any suggestion would be appreciated. 

Download Equation.mw

Thanks.

How much MB of data one can compile in single worksheet without fear of crashing?

I asked this question because I have maple worksheet with almost 1000 of lines, initially sheet use to open very quickly but as soon as data started piling up the opening of worksheet slowdown significantly.

Should I worry about such slowdown due to large amount of data in worksheet or should I need to create another worksheet to divide data??

Regards

hi,

i want to compute the determining PDE system satisfied by the infinitesimals, such as the KdV equation.

but i have a problem, if i use the command

DeterminingPDE(PDE1, integrabilityconditions = false, split = false)

i can get the coefficients of independent objects, but u[t] exists. 

i want to replace u[t] by (-u[x]u-u[x,x,x]), then extract the coefficients.

but i can't collect the coefficients. 

my code:

with(PDEtools, DeterminingPDE, declare, diff_table, casesplit, InfinitesimalGenerator, Infinitesimals, SymmetryTest, ReducedForm, FromJet, ToJet);

declare(u(x, t));

U := diff_table(u(x, t));

PDE1 := U[]*U[x]+U[t]+U[x, x, x] = 0;

DetSys := DeterminingPDE(PDE1, integrabilityconditions = false, split = false);
detsys := FromJet(DetSys, u(x, t), differentiationnotation = diff);
pd1 := subs(U[t] = -U[]*U[x]-U[x, x, x], detsys); #u[t]->(-u[x]u-u[x,x,x])
pd2 := ToJet(pd1, [u(x, t)]);

how do i collect the coefficients?

help!

I want to ask., I put delta as my constant in maple program and I want the answer are in delta as well., but the thing is., when running., it let delta=0, delta=-1, and delta=delta.,
the condition is we cannot let delta=1 or delta=0 because it is just same for s5 and s7.,.(delta is refer to the s8). How can I get answer as delta? with the condition? here I attach my maple programme..

> derivation := proc (A, n)
local i, j, k, t, s5, s7, s8, m, D,
sols5, sols7, sols8, eqns5, eqns7, eqns8,
BChange5, BChange7, BChange8; eqns5 := {}; eqns7 := {}; eqns8 := {};
D := matrix(n, n);
BChange5 := matrix(n, n); BChange7 := matrix(n, n); BChange8 := matrix(n, n);
for i to n do for j to n do for m to n do
s5 := sum(0*A[i, j, k]*D[m, k], k = 1 .. n)-(sum(A[k, j, m]*D[k, i]+A[i, k, m]*D[k, j], k = 1 .. n));
s7 := sum(0*A[i, j, k]*D[m, k], k = 1 .. n)-(sum(A[k, j, m]*D[k, i]+0*A[i, k, m]*D[k, j], k = 1 .. n));
s8 := sum(0*A[i, j, k]*D[m, k], k = 1 .. n)-(sum(A[k, j, m]*D[k, i]+delta*A[i, k, m]*D[k, j], k = 1 .. n));
eqns5 := `union`(eqns5, {s5}); eqns7 := `union`(eqns7, {s7}); eqns8 := `union`(eqns8, {s8})
end do end do end do;
sols5 := [solve(eqns5)]; sols7 := [solve(eqns7)]; sols8 := [solve(eqns8)];
t := nops(sols5); t := nops(sols7); t := nops(sols8);
for i to t do for j to n do for k to n do
BChange5[k, j] := subs(sols5[i], D[k, j]);
BChange7[k, j] := subs(sols7[i], D[k, j]);
BChange8[k, j] := subs(sols8[i], D[k, j])
end do end do;
print("eqns&Assign;", eqns5); print("sols:=", sols5); print("BChange5:=", BChange5);
print("eqns&Assign;", eqns7); print("sols:=", sols7); print("BChange8:=", BChange7);
print("eqns&Assign;", eqns8); print("sols:=", sols8); print("BChange8:=", BChange8)
end do end proc;

> AS1 := array(sparse, 1 .. 2, 1 .. 2, 1 .. 2, [(1, 1, 2) = 1]);
> derivation(AS1, 2);

> AS2 := array(sparse, 1 .. 2, 1 .. 2, 1 .. 2, [(1, 1, 1) = 1, (1, 2, 2) = 1]);
> derivation(AS2, 2);

> AS3 := array(sparse, 1 .. 2, 1 .. 2, 1 .. 2, [(1, 1, 1) = 1, (2, 1, 2) = 1]);
> derivation(AS3, 2);

> AS4 := array(sparse, 1 .. 2, 1 .. 2, 1 .. 2, [(1, 1, 1) = 1, (2, 2, 2) = 1]);
> derivation(AS4, 2);

> AS5 := array(sparse, 1 .. 2, 1 .. 2, 1 .. 2, [(1, 1, 1) = 1, (1, 2, 2) = 1, (2, 1, 2) = 1]);
> derivation(AS5, 2);

> AS1 := array(sparse, 1 .. 3, 1 .. 3, 1 .. 3, [(1, 3, 2) = 1, (3, 1, 2) = 1]);
> derivation(AS1, 3);

> AS2 := array(sparse, 1 .. 3, 1 .. 3, 1 .. 3, [(1, 3, 2) = 1, (3, 1, 2) = alpha]);
> derivation(AS2, 3);

> AS3 := array(sparse, 1 .. 3, 1 .. 3, 1 .. 3, [(1, 1, 2) = 1, (1, 2, 3) = 1, (2, 1, 3) = 1]);
> derivation(AS3, 3);

> AS4 := array(sparse, 1 .. 3, 1 .. 3, 1 .. 3, [(1, 3, 2) = 1, (2, 3, 2) = 1, (3, 3, 3) = 1]);
> derivation(AS4, 3);

> AS5 := array(sparse, 1 .. 3, 1 .. 3, 1 .. 3, [(2, 3, 2) = 1, (3, 1, 1) = 1, (3, 3, 3) = 1]);
> derivation(AS5, 3);

> AS6 := array(sparse, 1 .. 3, 1 .. 3, 1 .. 3, [(3, 1, 2) = 1, (3, 2, 2) = 1, (3, 3, 3) = 1]);
> derivation(AS6, 3);

> AS7 := array(sparse, 1 .. 3, 1 .. 3, 1 .. 3, [(1, 2, 1) = 1, (2, 2, 2) = 1, (3, 1, 1) = 1, (3, 3, 3) = 1]);
> derivation(AS7, 3);

> AS8 := array(sparse, 1 .. 3, 1 .. 3, 1 .. 3, [(1, 3, 1) = 1, (2, 3, 2) = 1, (3, 1, 1) = 1, (3, 3, 3) = 1]);
> derivation(AS8, 3);

> AS9 := array(sparse, 1 .. 3, 1 .. 3, 1 .. 3, [(2, 3, 2) = 1, (3, 1, 1) = 1, (3, 2, 2) = 1, (3, 3, 3) = 1]);
> derivation(AS9, 3);

> AS10 := array(sparse, 1 .. 3, 1 .. 3, 1 .. 3, [(1, 3, 1) = 1, (2, 3, 2) = 1, (3, 1, 1) = 1, (3, 2, 2) = 1, (3, 3, 3) = 1]);
> derivation(AS10, 3);

> AS11 := array(sparse, 1 .. 3, 1 .. 3, 1 .. 3, [(1, 3, 2) = 1, (2, 3, 2) = 1, (3, 1, 2) = 1, (3, 2, 2) = 1, (3, 3, 3) = 1]);
> derivation(AS11, 3);

> AS12 := array(sparse, 1 .. 3, 1 .. 3, 1 .. 3, [(1, 1, 2) = 1, (1, 3, 1) = 1, (2, 3, 2) = 1, (3, 1, 1) = 1, (3, 2, 2) = 1, (3, 3, 3) = 1]);
> derivation(AS12, 3);

> AS13 := array(sparse, 1 .. 3, 1 .. 3, 1 .. 3, [(1, 1, 1) = 1, (2, 2, 2) = 1, (3, 3, 3) = 1]);
> derivation(AS13, 3);

> AS14 := array(sparse, 1 .. 3, 1 .. 3, 1 .. 3, [(1, 2, 1) = 1, (2, 1, 1) = 1, (2, 2, 2) = 1, (3, 3, 3) = 1]);
> derivation(AS14, 3);

> AS15 := array(sparse, 1 .. 3, 1 .. 3, 1 .. 3, [(1, 2, 1) = 1, (2, 2, 2) = 1, (3, 3, 3) = 1]);
> derivation(AS15, 3);

> AS16 := array(sparse, 1 .. 3, 1 .. 3, 1 .. 3, [(2, 1, 1) = 1, (2, 2, 2) = 1, (3, 3, 3) = 1]);
> derivation(AS16, 3);

> AS17 := array(sparse, 1 .. 3, 1 .. 3, 1 .. 3, [(1, 1, 2) = 1, (3, 3, 3) = 1]);
> derivation(AS17, 3);
>

Dear all,

I am trying to solve a differential equation; 

diff(H(z), z) = 6.534101519*10^17*H(z)^2*(1.+z)^(5/2)+6.250000000*10^(-67)*sqrt(-1.639468135*10^119*H(z)^2*(1.+z)^5+9.161095674*10^82*(1.+z)^8+1.092978756*10^168*H(z)^4*(1.+z)^5)

sol := dsolve({test, H(0) = 2.268308490*10^(-18)}, numeric, range = 0 .. 3)

The problem is that it gives me the eror: 

Warning, cannot evaluate the solution further right of .25430145, probably a singularity

How can I get rid of this?

Dear all

I have the following equaion

Eq := diff(phi(x, k), x, x)+(k^2+2*sech(x))*phi(x, k) = 0;
          
The solution is given by 

phi := (I*k-tanh(x))*exp(I*k*x)/(I*k-1);

My question : At what value of k is there a bound state and in this case can we give a simple form of the solution phi(x,k)

With best regards

How I can simulate control speed of car with sensor of speed, noise, feedback on maplesim?thanks

I am (again) trying to get Maple to do some parallel work; using the Threads package.

My actual problem involves a vector function with 6 elements, acting on 6-vectors. Each element of the output vector is calculated as a high-order polynomial of all 6 input elements. The whole thing is a map that I want to iterate. I plan to evaluate each of the 6 functions in a separate thread (the input vector of course is the same for all six) and then put the results together in a Vector, to be used as input for the next iteration.

Facing difficulty I finally wrote myself a little toy program to check out the basic mechanism. Here it is:

restart;
                "Maple Initialization loaded..."
with(Threads):
f:=x -> 1+x^2;
                                       2
                        f := x -> 1 + x
x:=0:
tt:=time[real]():

for i from 1 to 10 do
  id:=Create(f(x),y):
  Wait(id):
  x:=y:
  y:='y':
end do:

time[real]()-tt;
                             0.018
i;
                               11
So far so good; even the output (not shown) makes sense. BUT: as I increase the number of iterations in the for...do loop, the memory allocation goes up fast, and I hit a point at about 40 iterations where the whole process locks up and the program never ends, cannot even be stopped (at least for 100 iterations), forcing me to abort the whole thing. I have evidence that Maple allocates vast amounts of memory which finally chokes the whole thing (on a 16 GB-RAM machine).

Anyone have any idea what I am doing wrong? I realize the above example does not provide benefits; in the real example there will be 6 Creates and the loop will Wait for all of these to finish.

I'd really like to get this to work as each function can take quite some time and I do expect at least some speed-up from parallelizing this (even after overhead).

This is on Maple 2015 on Mac OS X 10.10.5 with 16 GB of RAM. I should mention that I set UseHardwareFlots:=true in my .mapleinit file.

Thanks,

M.D.

H2 := [a(t)*(diff(c(t), t))+b(t) = 100, a(t)*(diff(b(t), t))+c(t)*(diff(b(t), t)) = exp(t), a(t)*(diff(c(t), t))+a(t)*(diff(b(t), t))+b(t) = 90];
H1 := subs([diff(a(t),t)=a1,diff(b(t),t)=b1,diff(c(t),t)=c1], H2);
H := subs([a(t)=a0, b(t)=b0, c(t)=c0], H1);
ics := generate_ic(H, {a0=-2..2, b0=-2..2, c0=-2..2,a1 = -2 .. 2, b1 = -2 .. 2, c1 = -2 .. 2, t = 0, energy = 0}, 100);

Error, (in generate_ic) invalid input: `DEtools/generate_ic` expects its 1st argument, H, to be of type algebraic, but received [a0*c1+b0 = 100, a0*b1+c0*b1 = exp(t), a0*c1+a0*b1+b0 = 90]

Hello,

After trigonometric manipulations in a mechanical problem, I can obtain the desired angles but defined with modulo 2Pi.

I would like to program or find a function which can do this operation :

While angle doesn't belong to [-Pi, Pi]

do 

  If angle > Pi then do angle = angle - 2Pi

  If angle < - Pi then do angle = angle + 2Pi

end

Is there an existing function which can do this operation ?

Otherwise, may you help me to program it ?

Thanks a lot for your help

Dear all;

I need your help to solve the non-square system of equation

restart;
with(LinearAlgebra);
 l1 := [1, 1, 1, 0, 0, 0, 0, 0, 0];

l2 := [0, 0, 0, 1, 1, 1, 0, 0, 0];

l3 := [0, 0, 0, 0, 0, 0, 1, 1, 1];

l4 := [1, 0, 0, 1, 0, 0, 1, 0, 0];

l5 := [0, 1, 0, 0, 1, 0, 0, 1, 0];

l6 := [0, 0, 1, 0, 0, 1, 0, 0, 1];

l7 := [0, 0, 1, 0, 1, 0, 1, 0, 0];

A := Matrix([l1, l2, l3, l4, l5, l6, l7]);
    # Unknown vector                    

m := [m1, m2, m3, m4, m5, m6, m7, m8, m9];
# Right hand side                  

 b = [15, 15, 15, 15, 15, 15, 15];

# Let the matrix equation : A m =b

1)I need your help to compute the kernel and general solution of this matrix equation

2) can we find a solution if m_k in { 2 3 4 5 6 7 8 } and each of these number appears at least once

3) If there a solution if we consider m_k in the set {0 1 2 3 4 5 6 7 8 }  and the number used exactly one

Thank you very much for your help