Hello,

I have another question. I would like to construct a code, demonstrating the loss of information when sending codewords.  Usually, one assumes that each entry of the codeword has a chance equal to p  (like p=0.17) of being incorrectly sent.  How can I have such a random element in my code?  

Thank you,

fredbel6

I have a 2D and a 3D plot which are close together and I would like them to have a similar look. However, when I set the caption with:

caption=["whatever text I want here", font=[HELVETICA,BOLD,12]]

I get what appears to be different fonts on the two plots.

Any suggestions as to whether I am doing something wrong please?

(And does Maple not allow me to use any font I want?)

Many thanks

Karina

I downloaded John Fredsted's Gravitation code from the Maple application center, and now I'm trying to get it to be a package.

However, I'm having trouble doing this.

Can anyone help me get to the point where I can access this application as any other manufacturer produced package using the with command ?

v/r,

Hey

I was discusing Maple and Matlab with one of my friend.

He said that in Matlab he can do

a:=1:12

b:=sin(a)

plot(a,b)

that's easy in matlab to do so

i use

> ptlist:=NULL:
> for n to 12 do
> ptlist:=ptlist,[n,sin(n)]:
> od:
> plot([ptlist]);

do to so

is there any easy way to do that in maple?

like creat a sequence from 1 to 12? ( besides seq(n,n=1..12))

thanks

dsolve( {diff(x(t),t)=sqrt(x(t)), x(0)=0}, x(t));

use the theorem to test the ODE ,the solutions are unique

however maple gives me a unique solution?

I was hoping to fit a cylinder to some data points in 3d space and find the equation of the long axis of the cylinder.

Sample data (actual data much larger matrix):

Hello
I have a problem with Maple. I would like to compute following sum using differentiation:

an:=x^(4*n-3)/(4*n-3)

This power series is convergent for x in (-1,1).

Sum(an,n=1..infinity);

diff(%,x);

s1:=value(%);

pf:=convert(s1,parfrac);

Now when integrating:

subs(x=t,pf);

int(%,t);

the result is: 1/2*arctan(t)-1/4*ln(t-1)+1/4*ln(t+1) .

The problem is that ln(t-1) is not defined for t in (-1,1). This is caused by integration of the equation:

-1/4/(t-1)

which is

Here is a system to ODE i am trying to solve:

w(t) = x(t) + x'(t) + w(t-a)

x''(t) = x'(t) + w(t)

How can i solve this kind of ODE with delay in time?

aks.

I have found this free library for Maple. It has got a lot of new or improved commands.

http://www.download.com/Aladjev-s-Library-for-Maple/3000-2070_4-10716687.html

In a recent blog entry, I proposed an easy way to plot the region between two curves. Later I read from an earlier blog entry that “filled=true” in implicitplot can produce amazing effects for plotting regions. Inspired by the blog entry, I’d like to introduce another easy way to plot the region between two curves.

To plot the region between y=f(x) and y=g(x) (x=a..b), we just need the following code:
with(plots):

f:=x->f(x): g:=x->g(x):

implicitplot(y=0, x=a..b, y=f(x)..g(x), filled=true, coloring=[green,green]);

The key to the success of this code is that Maple 8 allows varying range for the second variable y (i.e. y=f(x)..g(x)). However I was sorry to find that this is not allowed in Maple 11 (This will be addressed later.) .

Example 1  The region between y=x and y=x^2.

with(plots):

f:=x->x:g:=x->x^2:

a:=0: b:=1:

region:=implicitplot(y=0,x=a..b,y=f(x)..g(x),filled=true,coloring=[yellow,yellow]):

F:=plot(f(x),x=a-0.2..b+0.2,thickness=3,color=red):

G:=plot(g(x),x=a-0.2..b+0.2,thickness=3,color=blue):

display(F,G,region,scaling=constrained);

Example 2 The region between y=sin(x) and y=cos(x).

with(plots):

f:=x->sin(x):g:=x->cos(x):

a:=0: b:=6:

region:=implicitplot(y=0,x=a..b,y=f(x)..g(x),filled=true,coloring=[grey,grey]):

F:=plot(f(x),x=a-0.2..b+0.2,thickness=3,color=red):

G:=plot(g(x),x=a-0.2..b+0.2,thickness=3,color=blue):

display(F,G,region,scaling=constrained);

Now if we reverse the order of the range options from “x=a..b, y=f(x)..g(x)” to “y=f(x)..g(x), x=a..b”, some strange but interesting thing will happen (See Example 3）.

Example 3

with(plots):

f:=x->sin(x):g:=x->cos(x):

a:=-1: b:=6:

region:=implicitplot(y=0, y=f(x)..g(x),x=a..b, filled=true,coloring=[grey,grey]):

F:=plot(f(x),x=a-0.2..b+0.2,thickness=3,color=red):

G:=plot(g(x),x=a-0.2..b+0.2,thickness=3,color=blue):

display(F,G,region,scaling=constrained);
 

It can be seen that the region in Example 2 has been reflected with respect to the line y=x. But this is not bad because can use this phenomenon to plot regions between curves x=f(y) and x=g(y) (See Example 4).

Example 4  The region between x=y^2/2 and x=y^4/4-y^2/2.

with(plots):

f:=y->y^4/4-y^2/2: g:=y->y^2/2:

region:=implicitplot(y=0,x=f(y)..g(y),y=0..2,filled=true,coloring=[grey,grey]):

F:=plot([f(y),y,y=-1..2.3],thickness=3):

G:=plot([g(y),y,y=-1..2.3],thickness=3,color=blue):

display(region,F,G,scaling=constrained);

Finally some questions to be answered or discussed.

    1. Is “coloring” used in the examples an option in the package Plots? But I cannot find it in the Help (Typing ? coloring produces no results.) .
   2. Why the strange but interesting thing happens in Example 3 ?

   3. Why the above method cannot be realized in Maple 11?
   If we input the following code in Maple 11,
with(plots):

implicitplot(y=0,x=0..1,y=x..x^2,filled=true,coloring=[yellow,yellow]);with(plots);
An error warning will occur:
Error, (in plots/implicitplot) invalid input: invalid range for second variable

This means varying range for the second variable y (eg. y=x..x^2) is not allowed in Maple 11 , but which is allowed in Maple 8. If this is true, then I doubt if Maple 11 is really stronger than its earlier versions in all respects.

I have a pointplot3d that is running in an infinite loop and I was wondering if there was any way to at the end of my loop show the graph, pause Maple for .1 seconds and delete the graph. Such as in the example:

n:=1;
keepGoing:=1;
 

while keepGoing=1 do
  plot(x^n, x=-5..5);
od;

is there any way I could get Maple to show the graph for .1 seconds then delete the current graph and show the next graph?

pHatfield

Dear all: Anybody could tell me how can I obtain this integral with maple? Int(exp^(-a*x^2)*sech(x/2)^2, x=-infinity..infinity); where "a" is positive thank a lot D. Reyes CBPF