Hello I am trying to plot this differential equation,  have not had any success can any one help me.

plot(q(t)= Ce^-1/2 + sin2t +cos4t)

not sure what i am doing wrong and i just used the plot command

Thanks

Hi everyone. Please excuse me in advance, as I am new on this website and to Maple.

So I am using Maple 16 and I want it to give me the derivative of a function that has constants in it, for example f(x)=(x-a)(x-b). I wrote the (probably stupid) commands on Maple:

> f(x):=(x-a)(x-b);

> diff(f(x), x);

but the result is not the expected (2x-a-b), but rather (D(x))(x-b)-(D(a))(x-b). What would be the right things to write to get what I need?

Thank you in advance,

David

Hello,

I'm trying to improve the fvisual aspect of a worksheet.

For some inputs or texts, I would like to reuse some formats.

Is a way to duplicate formatting such as for software like word or others ?

In others words, is there in Maple this kind of option   Duplicate formatting ?

Thanks a lot for your help.

Hello everyone,

I'm working on a simulation for standing wave to prove that the combination of 2 waves in opposite direction can create standing wave. So I use these:

> restart;
> with(plots):
> W1:=A*cos(omega*t-k*x);

> W2:=A*cos(omega*t+k*x);

> W:=W1+W2;

> SW:=(A,omega,k)->animate(plot,[{W1,W2,W},x=-4..4,y=-4..4,color=[red,green,blue],scaling=constrained],t=0..5,frames=10);

> display(SW(2,2*Pi,5),insequence);

It did work if SW is a function with one variable, now I need 3 variables (A,omega,k);

It said: "Plotting error, empty plot"

Please show me my mistake or an another method. Thank you

Download analytical_case_1.mw

Hi, I'm trying to create a procedure like this;

f:=proc(a);
if a in RealRange(0,1) then a else no;
end if;
end proc;

 But when I try with f(0.5); for instance, I get the error: 

Error, (in f) cannot determine if this expression is true or false: .5 in RealRange(0, 1)

What am I doing wrong here, why can Maple not determine this?

Thank you! 

HI,

wondered if anyone knows how to make proper use of the large operators pallete on the list of pallettes on the left. For example when using the contour integration symbol on the left how do you enter the delimiters. 

I always get the error: "Error, unable to match delimiters". The help on this is not useful for this case. 

Thanks. 

Hi everyone, I'm a new one to Maple. I've just learnt some basic tools :)

This is my task. I tried to record in Maple but I had errors. I don't know why I had problems but I hope you will help me and I will do it.

tkanks

This is the code example_hw2.mw which derives from hw2_I1.mw.

hw2_I1.mw works but example_hw2.mw doesn't work and the differences between two codes are two new function I added to the dsolve which are η(t) and I2(t). The I2(t) is the second part of I1(t) at the interval t>t* which subject to Phi(t*)=0.

So how to make the sentence 'if |(H(t))/(omega)|>1 then eta(t)=0 else eta(t)=arccos(-(H(t))/(omega))' and 'I2(t) = (int(p(t), x = -eta(t) .. eta(t)))/Pi' work?

I would like to plot a 2D contour plot in the botton of a 3D plot of a spacial curve. I don't know how to do that in maple, but I found something similar done in Matlab for a 2Dcontour plot in the botton of a 3D surface.

Can someone help me?

Thanks,

Fernando 

Hi everyone,

One of my teachers got stuck in the last century and will not approve my turned in papers when i use "replace unit"
Can i make a global setting that makes all my watt results come up as MegaWatt ?

Hi,

    i meet  a partial differential equation seems not complicated

with(PDEtools):

PDE := (diff(f(x__1, x__2, p__1, p__2), x__1))*p__1/m-(diff(f(x__1, x__2, p__1, p__2), p__1))*(2*k*x__1-k*x__2)+(diff(f(x__1, x__2, p__1, p__2), x__2))*p__2/m-(diff(f(x__1, x__2, p__1, p__2), p__2))*(-k*x__1+2*k*x__2);

when i use

     pdsolve(PDE);

i get nothing,but i sure

    f=c*(p__1^2/m+p__2^2/m+4*p__1*p__2/m+6*k*x__1*x__2) 

is the one solution of the differential equation .

how i can get solutions about of the above equation.

thanks .

This is the code  hw2_final.mw

Let me explain it.

I am sure that the mistakes must be about the expresstion of the I1(t) and I2(t). Actually if you delete I1(t) and I2(t) , the whole code works and get the picture at the bottom. 

What I want is to put the expresstion of the I1(t) and I2(t) into 'sol:=dsolve...' and 'plots...' to get the picture of I1(t) and I2(t) with respect to t. Before the t* which subject to Phi(t*)=0 (The blue line in the picture at the bottom is Phi) I want I1(t) and after t* I want I2(t).

I1(t) = (int(sqrt(2*(H(t)+omega*cos(q(t)))), q(t) = q(t)-2*Pi .. q(t), numeric))/Pi.    what I want of this experesstion is to get  'int(sqrt(2*(H(t)+omega*cos(q(t)))' from  'q(t)-2*Pi' to 'q(t)' by numeric method.This q(t) is the solution of the ODE sys.

For example(the number I used is not true,just for example) , at the point t=20, q(t)=30-2*Pi.

so I1(t)= (int(sqrt(2*(H(t)+omega*cos(x))), x = 30-2*Pi .. 30, numeric))/Pi.The I2(t) I want is similar to I1(t).

How can I solve it?

Hello, 

I am pretty new to Maple and Im trying to find the parameters of an equation using some kind of fit routine but I can only find such a routine to fit an expression to data and not vice versa.

my equation is as follows

epsilon(E):= a0 + a1*ln(E) + a2*ln(E)^2 + a3*ln(E)^3

I do have data for E which I imagine I need. 

E:= {121, 244, 344, 411, 444, 778, 867, 964, 1085, 1112, 1212, 1299, 1408} all in keV :)

Any suggestions/help would be much appreciated, although I am new to the program so go easy on me :) 

Cheers

Hi, I'm searching through a text file looking at individual letters, characters etc.  As part of this I want to detect if the character is the control character for a new paragraph - carriage return, line feed. I believe the ASCII numbers for these are 13, 10 respectively. I'd like to know the code to do this, please.  It's something along the lines: CR:=???:  if c=CR then

where c is a character read from the text file.   ....but what goes in place of ???

Thanks, David