I have a differential equation system x'(t)=f1(k,t)*x(t)+f2(k,t)*y(t), x'(t)=g1(k,t)*x(t)+g2(k,t)*y(t) with initial condition x(0)=1 and y(0)=1. Here k is a parameter, f1, f2,g1, g2 are certain functions of k and t. I used dsolve and set k to be a parameter to solve the system numerically which gives you a procedure output. If I fixed k to be a specific numerical number, then I can use odeplot to plot x(t) VS t.

Now I set a range for k, say k=0..10. And I want to plot x VS (t,k) which is a 3D graph. How can I do this?

Hi MaplePrimers,

I've written a function that needs to be evaluated at a bunch of different points.  Evaluating it in a loop works. I'm wondering if there was a faster way to do this because I'm evaluating a list of 400k+ sets of points.  

Right now I'm using a loop with the following code.

for i from 1 to 500000 do 
     Results(i):= f(L[i][])[1];
od;

 

If I have a function f, which has 5 arguements, f(y, w, x,y,z).

I also have a list of those arguements:  L = [[1,2,3,2,3],[4,5,6,2,3],[7,8,9,2,3]]

What would be the fastest way to get a list of results?  Also, is there a way that I could preallocate memory for this list?

Ideally, I would like to get the output as as list.  ie:

Results:= [[f(1,2,3,2,3)], [f(4,5,6,2,3)], [f(7,8,9,2,3)]]

Hi all,

As we know that the differential of conjugate(z) is non-analytic.

But it seems that the diff gives the solution about the complex function conjugate(z)

What does it mean?

Hello guys, i have a system of equations ( dynamical system ) which i have its critical points but when i compute its critical points with maple i get different points , i dont know what is wrong . thank you for your time.

critical.mw

Is there any one to help me in calculating computational order of convergence of derivative free method. I am trying to calculate programs runs with immature error and does not print it.

Please is there any 1 to help.

Hello

Is it not possible to view page breaks in ypyr document in Maple? 

It will make it easier to at up at nice document??

Jakob

Hi! I'm trying to make a point plot and they must have different colors, like the CIE diagram. I wish they varied from red to blue in 31 steps, as shown in the picture (they are all black :\). Does anyone have any idea how to do this? The red line is for something else.

This the code for the dots:

Hi,

Can anyone help me to solve this system of equations in Maple?

solve({
(-(1*Rfd*(1-(Ladssec/Lfd)+((((1.007033 +1*(Laqssec+Ll))*Ladssec)/(((Ra+0.04527646)^2+(1.007033 +1*(Ladssec+Ll))*(1.007033 +1*(Laqssec+Ll)))*Lfd)) *Ladssec)))/(Lfd))=-0.0069
,(-(1*Rfd*(-(Ladssec/Lfd)+((((1.007033 +1*(Laqssec+Ll))*Ladssec)/(((Ra+0.04527646)^2+(1.007033 +1*(Ladssec+Ll))*(1.007033 +1*(Laqssec+Ll)))*L1d)) *Ladssec)))/(Lfd))=0.002689
,(-(1*Rfd*(-((Ra+0.04527646)/((Ra+0.04527646)^2+(1.007033 +1*(Ladssec+Ll))*(1.007033 +1*(Laqssec+Ll))))*(Laqssec/L1q))*Ladssec)/(Lfd))=0.00002647
,(-(1*Rfd*(-((Ra+0.04527646)/((Ra+0.04527646)^2+(1.007033 +1*(Ladssec+Ll))*(1.007033 +1*(Laqssec+Ll))))*(Laqssec/L2q)) *Ladssec)/(Lfd))=-0.00001362

,(-(1*R1d*(-(Ladssec/Lfd)+((((1.007033 +1*(Laqssec+Ll))*Ladssec)/(((Ra+0.04527646)^2+(1.007033 +1*(Ladssec+Ll))*(1.007033 +1*(Laqssec+Ll)))*Lfd))*Ladssec)))/(L1d))=0.1052
,(-(1*R1d*(1-(Ladssec/Lfd)+((((1.007033 +1*(Laqssec+Ll))*Ladssec)/(((Ra+0.04527646)^2+(1.007033 +1*(Ladssec+Ll))*(1.007033 +1*(Laqssec+Ll)))*L1d)) *Ladssec)))/(L1d))=-0.2585
,(-(1*R1d*(-((Ra+0.04527646)/((Ra+0.04527646)^2+(1.007033 +1*(Ladssec+Ll))*(1.007033 +1*(Laqssec+Ll))))*(Laqssec/L1q))*Ladssec)/(L1d))=0.0009122
,(-(1*R1d*(-((Ra+0.04527646)/((Ra+0.04527646)^2+(1.007033 +1*(Ladssec+Ll))*(1.007033 +1*(Laqssec+Ll))))*(Laqssec/L2q)) *Ladssec)/(L1d))=-0.0005093

,(-(1*R1q*(((Ra+0.04527646)/((Ra+0.04527646)^2+(1.007033 +1*(Ladssec+Ll))*(1.007033 +1*(Laqssec+Ll))))*(Ladssec/Lfd))*Laqssec)/(L1q))=-0.000292
,(-(1*R1q*(-((Ra+0.04527646)/((Ra+0.04527646)^2+(1.007033 +1*(Ladssec+Ll))*(1.007033 +1*(Laqssec+Ll))))*(Ladssec/L1d))*Laqssec)/(L1q))=0.0008507
,(-(1*R1q*(1-(Laqssec/L1q)+((((1.007033 +1*(Ladssec+Ll))*Laqssec)/(((Ra+0.04527646)^2+(1.007033 +1*(Ladssec+Ll))*(1.007033 +1*(Laqssec+Ll)))*L1q))*Laqssec)))/(L1q))=-0.04423
,(-(1*R1q*(-(Laqssec/L2q)+((((1.007033 +1*(Ladssec+Ll))*Laqssec)/(((Ra+0.04527646)^2+(1.007033 +1*(Ladssec+Ll))*(1.007033 +1*(Laqssec+Ll)))*L2q))*Laqssec)))/(L1q))=0.0003831

,(-(1*R2q*(((Ra+0.04527646)/((Ra+0.04527646)^2+(1.007033 +1*(Ladssec+Ll))*(1.007033 +1*(Laqssec+Ll))))*(Ladssec/Lfd))*Laqssec)/(L2q))=-0.001785
,(-(1*R2q*(-((Ra+0.04527646)/((Ra+0.04527646)^2+(1.007033 +1*(Ladssec+Ll))*(1.007033 +1*(Laqssec+Ll))))*(Ladssec/L1d))*Laqssec)/(L2q))=-0.03134
,(-(1*R2q*(-(Laqssec/L1q)+((((1.007033 +1*(Ladssec+Ll))*Laqssec)/(((Ra+0.04527646)^2+(1.007033 +1*(Ladssec+Ll))*(1.007033 +1*(Laqssec+Ll)))*L1q))*Laqssec)))/(L2q))=4.239
,(-(1*R2q*(1-(Laqssec/L2q)+((((1.007033 +1*(Ladssec+Ll))*Laqssec)/(((Ra+0.04527646)^2+(1.007033 +1*(Ladssec+Ll))*(1.007033 +1*(Laqssec+Ll)))*L2q))*Laqssec)))/(L2q))=-4.868

}, {L1d, L1q, Ladssec, Laqssec, Lfd, R1d, R1q, Rfd, Ra, Ll},useassumptions)

assuming Lfd ~= 0.1632, R1d~=0.0269, L1d~=0.0750, L1q~=-0.1350, Ladssec~=0.0500, Laqssec~= -0.1500, Rfd~=0.0016, R1q~= 0.0215, Ra~=0.005, Ll~=0.15

which theory can explain the interaction of composition of group for combination of composition of group

if succeed to search a list of groups, what is the next step research them?

Using maple 16. When I run a worksheet it adds in extra rows of the red >s. The attached example was run 3 times. How do I stop this happening?

Download worksheet_issue.mw

Hi, i have problem with this code: 

Spacer := proc (N, p, q, sa, sb, M) local A, B, r, PA, PC, PB, stan, krok, droga; A := -N; B := N; r := 1-p-q; PA := empirical[0., sa, 1-sa]; PC := empirical[q, r, p]; PB := empirical[1-sb, sb, 0.]; stan := 0; droga := stan; to M do if A < stan and stan < B then krok := random[PC](1)-2 elif stan = A then krok := random[PA](1)-2 elif stan = B then krok := random[PB](1)-2 end if; stan := stan+krok; droga := droga, stan end do; {}*plots[pointplot]([seq([i, droga[i+1]], i = 0 .. nops([droga])-1)], axes = BOXED) end proc

---------------------------------------------------------------------------------------------------------------------------------

i have error when i start procedure like: 

error, (in Spacer) cannot determine if this expression is true or false: 0 < random[empirical[.5, 0.5e-1, .45]](1)+8 and random[empirical[.5, 0.5e-1, .45]](1) < 12

My run command: Spacer(3,0.5,0.5,0.8,0.8,20);

Please help me.

Hello Hello everybody 
   I have to solve the following differential equation numerically 

I don't know why it says : Error, (in f) unable to store '[0.]/(0.17571268341557e16+[-0.25659510610770e15])' when datatype=float[8]

Help pleaase!

thank you !!!

Download systéme_complet.mw

Hi,

I have a file with arbitrary points which I want to connect with a surface. I have seen similar problems on this site but I can't fix my problem with the answers that are given, mainly because my points are just plain vectors. Can anybody help me? 
These are my points/vectors:

v1 := `<,>`(15, 6, 14.89);
v2 := `<,>`(15, 8, 14.72);
v3 := `<,>`(15, 10, 14.79);
v4 := `<,>`(15, 12, 14.95);
v5 := `<,>`(15, 14, 15.17);
v6 := `<,>`(15, 16, 15.43);
w1 := `<,>`(15/2, 4, 9.78);
w2 := `<,>`(15/2, 6, 9.95);
w3 := `<,>`(15/2, 8, 9.85); 
x1 := `<,>`(15*(1/3), 4, 8.71);
x2 := `<,>`(15*(1/3), 6, 8.44);
y1 := `<,>`(15/4, 4, 8.31); 

I can only plot the different points with 

with(plots);
pointplot3d({v1, v2, v3, v4, v5, v6, w1, w2, w3, x1, x2, y1}, scaling = CONSTRAINED, symbolsize = 20, color = red, axes = normal, labels = ["L/h", "n", "kg/m"]);

I hope someone can help me!

Hello,

I am trying to solve the equation (non-linear) with one variable t2 (please see bellow):

(35595.29412*(52040.0-2400.0*t2))*(11-t2)*exp(ln(-360.0*t2+29600.0)-(0.9803921570e-5*(-360.0*t2+59200.0))*t2)*exp(ln(52040.0-2400.0*t2)-8.804313725+.5176470590*t2)*(360000*(exp(ln(-360.0*t2+29600.0)-(0.9803921570e-5*(-360.0*t2+59200.0))*t2))^2+(620*(-360.0*t2+29600.0))*(1200*exp(ln(-360.0*t2+29600.0)-(0.9803921570e-5*(-360.0*t2+59200.0))*t2)-2.232000*10^5*t2+1.83520000*10^7))*exp(ln(-360.0*t2+29600.0)-(0.9803921570e-5*(-2760.0*t2+59200.0))*t2)/(360000*exp(ln(52040.0-2400.0*t2)-8.804313725+.5176470590*t2)*(exp(ln(-360.0*t2+29600.0)-(0.9803921570e-5*(-360.0*t2+59200.0))*t2))^2+(372000*((52040.0-2400.0*t2)*exp(ln(-360.0*t2+29600.0)-(0.9803921570e-5*(-2760.0*t2+59200.0))*t2)+(-360.0*t2+29600.0)*exp(ln(52040.0-2400.0*t2)-8.804313725+.5176470590*t2)))*exp(ln(-360.0*t2+29600.0)-(0.9803921570e-5*(-360.0*t2+59200.0))*t2)+(384400*(52040.0-2400.0*t2))*(-360.0*t2+29600.0)*exp(ln(-360.0*t2+29600.0)-(0.9803921570e-5*(-2760.0*t2+59200.0))*t2))^2 = 1/150

During evaluation of the solve command I received a warning that solutions may have been lost. How can I overcome this problem? Also, I need that t2>0.

Thanks in advance,

Dmitry 

Hi,

I have a linear system to solve.

mm:=proc(a,x,h,i)
local A,Z1,Z2,Z,F,result;  # to declare the local variable
A:=array(1..2,1..2,[[1,1],[a,a+h]]);
Z1:=evalf(int(1/(abs(y-x)+.000000001),y=a..a+h));
Z2:=evalf(int(y/(abs(y-x)+.000000001),y=a..a+h));
Z:=array([Z1,Z2]);
F:=evalm(inverse(A)&*Z);
result:=F[i]
end:

My questions: 

1) My exact Z1 is Z1:=evalf(int(1/(abs(y-x)),y=a..a+h)); but I ask if can I put

Z1:=evalf(int(1/(abs(y-x)+.000000001),y=a..a+h));

the same for Z2.

2) Can I writte in a simple form the vector Z.  Because, later, il have a second system contains Z1,Z2, Z3, Z4,Z5.  The difference between Z1 and Z2 is the variable "y" added in the integral of Z2.

Many thinks.