Dear all,

A stupid question.

I tried to create a density plot of the data but I only saw the method to plot graphs through equations. (Actually, I'm not very familiar with related statistical commands in Maple)

This is the histograph of my data:

And I want to get the density plot like this:

It seems that we can get the graph through "InteractiveDataAnalysis" but cannot print the graph into the worksheet or assign the graph to the variable.

How to create a density plot through data? Thanks.

AOA... I want to export system of linear equation into matrix form...

Help.mw

restart:

Eq1:=S*diff(f(x,t),x,t)+diff(f(x,t),x)^2-f(x,t)*diff(f(x,t),x$2)=diff(f(x,t),x$3);

BCs := {D[1](f)(0,t)=cos(t), f(0,t)=0,D[1](f)(L,t)=0};

ICs := {f(x,0)=0};

S:=10:L:=5:
smod3:= pdsolve(Eq1,ICs union BCs,numeric,range=0..L);

smod3:-plot(t=0,  color=red):

it seems to me that the problem is due to the mixed bcs. Any way around?

Cheers!

Dear All,

I analyzed some example of linear equation systems and tried to distinguish the difference between the solve and fsolve in these cases.

1. In general case, the deviation between solve and fsolve is less than 10^-8, for example:

But, in some case, the deviation is more than 10^-7, for example:

how to reduce the error of solving the problem by fsolve?

2. It seems that solve will automatically translate the answer into numerical result while the system is composed with decimals, for example, we redo the second case with no decimals:

Is it possible to get the exact solution while the decimal is involved in the system?

The related file is attached. I'd appreciate any help on this topic. Thank a lot.

solve_and_fsolve.mw

Question_.pdf

this question about midpoint method I need help with the part c

thanks

I have the following nonlinear Differential Equation and don't know how to solve.  Can anyone give me any hints on how solvle for E__fd(t).  I don't even know the specific classification (other than nonlinear) of this DE can someone at least give me hint on that. Thanks.

.5*(diff(E__fd(t), t)) = -(-.132+.1*e^(.6*E__fd(t)))*E__fd(t)+0.5e-1

Thanks,

Melvin

I can't simplify the expression of 

(1/a[x])^(-k-1+epsilon)/(1/a[I])^(-k-1+epsilon)

to 

(a[x]/a[I])^(k+1-epsilon);

Please tell me how to do this.

Thank you in advance.

Taro yamada

1.which rules or theorems can guide to generate relations for words in group theory?

2.Is topological method such as complexes the direction to answer Question 1?

I am running a set of diffrential equation , but i receive below error

"Error, (in LL) cannot evaluate the solution past the initial point, problem may be complex, initially singular or improperly set up"

I can't understand the problem

restart:

Eq1:=diff(f(x),x$4)+(f(x)*diff(f(x),x$3)-diff(f(x),x$1)*diff(f(x),x$2))=0;

Eq2:=diff(f2(x),x$2)+f(x)*diff(f2(x),x$1)=0;

bcs:=f(0)=0,(D@@2)(f)(0)=0,f(1)=0,D(f)(1)=1,f2(-1)=0.5,f2(1)=1;

dsolve({Eq1,Eq2,bcs},numeric,output = listprocedure);

Error, (in dsolve/numeric/process_input) boundary conditions specified at too many points: {-1, 0, 1},

can only solve two-point boundary value problems

How to handle such problem using dsolve?

Cheers!

I suppose you would have to programme this, because I couldn't find anything relating to vector spaces in my Maplesoft Linear Algebra tutor or package.

My question really is, you have a problem like, the set of all pairs of real numbers of the form (1,x) with the operations (1,y)+(1,y')=(1,y+y') and k(1,y)=(1,ky) 

( ^ taken straight out of my homework haha)

and you run through the 10 vecctor space axioms to determine whether it fails and it not a vector space, or it passes all and it is a vector space.

Is there a way to do this in Maplesoft?

Hell

I write this code and didn't work , I have some erorrs as

Warning, The use of global variables in numerical ODE problems is deprecated, and will be removed in a future release. Use the 'parameters' argument instead (see ?dsolve,numeric,parameters)
Warning, cannot evaluate the solution past the initial point, problem may be complex, initially singular or improperly set up

also I have question " How I can change the scale of plot"

parameters := [z = 0, Omega = 2.2758, tau = 13.8, T2 = 200, omega0 = 1, r = .7071, s = 2.2758, H = 1.05457173*10^(-34), omega = .5, k = 1666666.667, Delta = 1.7758]

sys1 := {diff(u(t), t) = s*v(t)-u(t)/T2, diff(v(t), t) = -s*u(t)-2*Omega*exp(-r^2/omega0^2-t^2*1.177^2/tau^2)*cos(kz-`ωt`)*w(t)-v(t)/T2, diff(w(t), t) = 2*Omega*exp(-r^2/omega0^2-t^2*1.177^2/tau^2)*cos(kz-`ωt`)*v(t)}; ICs1 := {u(-20) = 0, v(-20) = 0, w(-20) = -1}

ans1 := dsolve(`union`(eval(sys1, parameters), ICs1), numeric, output = listprocedure); plots:-odeplot(ans1, [[t, u(t)], [t, v(t)], [t, w(t)]], t = -20 .. 20, legend = [w, v, u])

U := eval(u(t), ans1); F := eval(((-2*10^33*Omega*H*r*U(t))*(1/omega0^2))*exp(-r^2/omega0^2-t^2*1.177^2/tau^2)*cos(kz-`ωt`), parameters)

plot(F, t = -20 .. 20)

if there is a set of identities, such as a+b = b+a, a^2 = 2*a + 1

and one input or a few input,

how to make use of these identities to derive some output?

any algorithm can do this?

Hi,

I'm new here and I couldn't find similar problem in this forum.

I want to use variable (red marked) with unit definite integrals but it doesn't work. I put the file with units and file without units (to check correct solution) in this post.

What to do?

Files:

01_referat(units).mw

01_referat(without_u.mw

Is there any simple way in maple 16 to fix the axis width and height on inline plot? The PlotSetup seems dosen't function properly in my windows7 home 64 bit! Thank you.