Hi,

I am trying to solve following expression

int(int((1-exp(-5.5/cos(x)))*sin(x), x = 0 .. arctan(300*cos(y)+sqrt(12.25-90000*sin(y)^2))), y = 0 .. Pi)

But I am not getting results.

Please help me!!!

Thanks

I need to change the color of all elements of a plot by command.

I know that it is possible in interactive mode (see online maple help) but I would like to select the elements of a plot by line command and change color.

I would at first produce the plot with some color and then change only color of elements without reproduce the whole plot.

How can I do it ?

Thank you.

Cannot calculate derivative (gradient) of a procedure returned by dsolve.

Say, I solve the equation:

S1 := dsolve([diff(y(x), x$2)-1.0325*diff(y(x), x)+1.36*y(x)=sin(2*x), y(0)=0, y(1)=1], numeric, y(x), 'output' = listprocedure);

Its solution easily can be retrieved and looks fine:

H:=rhs(S1[2]); 

plot(H(t), t = 0..1, thickness = 4);

But when I try to calculate the gradient of H, I receive the error:

H1 := codegen[GRADIENT](H);

Error, (in intrep/statement) unable to translate Array(1..4, {(1) = proc (outpoint) local X, Y, YP, yout, errproc, L, V, i; option `Copyright (c) 2000 by Waterloo Maple Inc. All rights reserved.`; X := Vector(8, {(1) = .0, (2) = .14817993189456188, (3) = .31785812820433257, (4) = .47163479035679234, (5) = .6130306894371967, (6) = .7460958115245858, (7) = .8741894219027533, (8) = 1.0}, datatype = float[8], order = C_order); Y := Matrix(8, 2, {(1, 1) = .0, (1, 2) = .47692145669848085, (2, 1) = 0.7710429970702501e-1, (2, 2) = .5707930170882397, (3, 1) = .1866916935738028, (3, 2) = .7299040171277492, (4, 1) = .3128649714509215, (4, 2) = .9171936...

Gradient of procedures defined by  ":= proc()" is calculated properly.

When you label a function of curve, this label is put just next to it. Is there a way to move this label to another position of the same curve?

Hello guys

I have a coupled linear differentional equation which are in the 4th order. they are shown in the below:

P:=phi(x):
Q:=psi(x):

eq1:=a11*diff(P,x,x,x,x)+a22*diff(P,x,x)+a33*P+a44*diff(Q,x,x)+a55*Q:
eq2:=a44*diff(P,x,x)+a55*P+a66*diff(Q,x,x)+a77*Q:

eq1:=0:
eq2:=0:

The boundary values for this coupled equation are:
phi(a)=sigma1,phi(-a)=sigma1,diff(P,x)(a)=0,diff(P,x)(-a)=0,psi(a)=sigma2,psi(-a)=sigma2

Now consider:

a11:=6.36463*10^(-10):
a22:=-1.22734*10^(-9):
a33:=3.48604*10^(-10):
a44:=2.94881*10^(-11):
a55:=-5.24135*10^(-11):
a66:=-1.03829*10^(-9):
a77:=4.86344*10^(-10):
when I use dsolve for deriving a good answer in this equation, there are six real roots .How can I solve it with these boundary condition?

I need to extract phi(x) and psi(x) from this coupled equation.

Thanks

Hello friends!

I 'm a student and I don't know a lot about Maple, so I would be really grateful if anyone could help me.

I want to solve a system of two equations and I have two unknowns, which are k and εα. However I don't know what I am doing wrong and I can't solve it.

I have attached my file.

Thank you very much in advance!agogos_2.mw

Dear people in Mapleprimes,

I have a question about the ordering of monomials in a polynomial.

I hope you will help me understand how Maple works about it.

I inputed the polynomial as is written in black below.

Then, the outcome was blue, which ordering I could understand well: total degree ordering where at first 

those who have the order of 6 are collected which are 14 x^3*y^3, 6x*y^5, and then the following was those which 

have the order of 5: 21*x^5, -35 x^4*y, 9*x^3*y^2,-15*x^2*y^3, ... and so on.

And, among those who have the same order, lexical ordering was done, that is among 14 x^3*y^3, 6x*y^5, one which 

came first was the one with the larger degree about x, and among 21*x^5, -35 x^4*y, 9*x^3*y^2,-15*x^2*y^3, 

the first was 21*x^5, the second was -35*x^4*y, and so one, which was the ordering following the exponent about x.

And, then, I calculated Factor(polynomial) mod 7, which meaning I know.

Then, the result was 2*(x*y+2)*(3*y^3+x^2+3x*y)y.

I can understand the ordering among x*y and 2 in x*y+2, and that among 3y^3, x^2 and 3x*y in 3y^3+x^2*3x*y.

But, I can't understand why (x*y+2) comes at the first term, with 3 y^3+x^2+3x*y following it, and with y coming last.

This might be a trivial question. But, I hope you will teach me about this.

Best wishes.

taro 

Download heck_mod.mw

I am trying to fit an experimental data C[A](t)  vs t, with modelled ODE equation by solving it with numerical method. But the process gives problems here ha code and also find attached maple file.

Input is time =[0, 30, 60, 90, 120, 150, 180, 210, 240]

and output exptal data = [7647.5, 7397.5, 6755, 6252.5, 5860, 5530, 5440, 5107.5, 4857.5]

I want to find k,K[A] parameters;

EXPT_datafittinh_LHHW.mw

For my research at my school, I need to plot the Schrodinger equation using my given wave function. I am having issues though as I am receiving an error telling me that I need to submit my argument in standard or parametric form.

restart;

schro := {[4*(x^2-1)*(diff(psi(x, y), x, x))/(x^2-y^2)+2*x*(diff(psi(x, y), x))-(y^2-1)*(diff(psi(x, y), y, y))-2*y*(diff(psi(x, y), y))+(-2/(x+y)-2/(x-y)+1)*psi(x, y)] = energy};

psi := proc (x, y) options operator, arrow; e^((-1)*.5*[2*x+2*y])+e^((-1)*.5*[2*x-2*y]);

plot3d(schro, x= 1..100, y = -1 ..1);

Unfortunately, I am unable to plot my function. I was able to substitute my psi(x,y) function into my schro equation, but I am unable to do much else. I want to plot my function such that my energy is represented in the z-axis as a relationship between x and y which are a specific coordinate system (conical coordintes). 

files.mw

From art of problem solving ws: "Jamal wants to save 30 files onto disks, each with 1.44 MB space. 3 of the files take up 0.8 MB, 12 of the files take up 0.7 MB, and the rest take up 0.4 MB. It is not possible to split a file onto 2 different disks. What is the smallest number of disks needed to store all 30 files?"

The answer is 13: 3*[0.4,0.8]+6*[0.7,0.7]+4*[0.4,0.4,0.4]

How to accomplish this in maple? my attempt doesnt work, unsurprisingly...

How do you move plot labels individually? Just click-hold-and-drag does not work.

"A Virtual 3D Solar System": http://www.maplesoft.com/applications/view.aspx?SID=4484&view=html#mapleautobookmark5

How do you color the orbits individually?

I am also not sure how to program a check in the code to determine that dsolve solved the differential equation.

For example

ode:=diff(y(x),x)-a*(x^n-x)*y(x)^3-y(x)^2=0;
sol:=dsolve(ode,y(x));

In this case, sol is () as it could not solve it. When I tried odetest, I get an error

odetest(sol,ode);

Error, invalid input: odetest uses a 2nd argument, ODE, which is missing

What is the correct way to check dsolve was successful that will work for all cases? I am looking for programmable method, no GUI use.

In Maple help on int, it says

"If Maple cannot find a closed form expression for the integral, the function call itself is returned"

But then, what is the correct way to check for this in the code? How do I know that the result returned is the call I made? (it would have been easier if these functions throw an error, or set some status code that one can check for success or failure).

Hello friends;

I uploaded the file. Firstly i solved the 4. order ode. I converted it to trigonometric functions from exponantial.

I have 4 equation and 4 unkowns. I thought , it is sufficient to solve this. As you see , i can not solve the system .

May you help me please where i am doing wrong. 

Thanks.

odev4.mw

(PS:i downloaded the file again correctly)

How do you plot different kinds of data simultaneously in one graph? E.g. surfdata and spacecurve?