Maple Questions and Posts Maple Questions and Posts Feed

These are Posts and Questions associated with the product, Maple

If there is  an equation or are several equations, I need to obtain all the roots, how can I do???

 

fsolve ? rootfindings? or what?

 

If an examples of actual is given,  That will be perfect  !!!

 

Thanks 

Hi, there

How can we plot the volume of revolution of the region between two curves y=2x-x^2 and y=sqrt(2x-x^2) around the x-axis?

Any help will be appreciated. I used a command in maple 13 but the result was a sphere!

Regards

Yegan

Hi, I am new to Maple. I want to plot a graph in a separate window from command-line maple. I tried the following code and getting this error

> plotsetup(window);
> plot(x,x=-10..10);
Plotting error, no plot device driver for plotdevice=window
>

 

I tried maplet but I am not getting the plot

> plotsetup(maplet);
> plot(x,x=-10..10);
Initializing Java runtime environment.
>

 

What should I do to get the plot??

Hello,

I have a procedure wich is something like 

 

F:=proc(a,b,l) limit(f(a,b),b=l); end proc;

For my specific problem, the limit always exists and is a well defined function

After that, I would like to generate other functions, depending on F(a,b,l), e.g.:

 

G:=proc(a,b,N) add(F(a,b,l),l=1..N); end proc;

 

However, when I tried to do that, Maple inserts in G an unevaluated F, depending on the results of the limits. This makes G not work properly (unevaluated), since the limit is not computed before G. I tried to use some intermediate steps, like using unapply command, but it does not works.

If someone can help, I would appreciate.

 

 

Hi,

I have a problem with maple solving diffusion equation. I solved the equation as follows

Es := 0.117108e12;
Ef := 0.78125e11;
l := 0.150e-6;
s := 0.500000e-3;
f := 0.5898334197e-6;
o := 0.9e-5;
d := 0.10e-17;
cb := 0.1e7/(19.9);
c := l*f/(d*cb);
PDE := diff(u(x, t), t)-(diff(u(x, t), x, x)) = 0;
IBC1 := {u(x, 0) = 0, (D[1](u))(0, t) = 0, (D[1](u))(1, t) = c};
S1 := pdsolve(PDE, IBC1, numeric, time = t);
S1:-plot(t = 0.6e-2);

i am plotting cincentration along the thickness of the material. i want to know why the concentration is negative. It should not be negative because constant flux 'c' is present at x=1. and flux at x=0 is 0, and also the initial concentration is 0.

Thanks

 


How can I plot the volume of revolution of the region between the curves y=ln(x) and y=-ln(x)on the interval [1,e]

around the y-axis.please specify the command. I used the command: VolumeOfRevolution(ln(x),-ln(x), x=1..e, scaling=constrained,axis=vertical,output=plot). But this command only plots the revolution of the curves not the region between them.

Best Regards

Yegan 

Hi,

I would like to plot E2(t) , but It gives errors. How can I avoid the singularity and solve this problem?


restart: with(plots):
with(Student[NumericalAnalysis]):
g1:=(x,t)->(-sqrt(t)/(2*sqrt(Pi*r^3)))*(sin((r*(x-1)^(2)/(4*t))+(Pi/4))-sin((r*(x+1)^(2)/(4*t))+(Pi/4))):

g2:=(x,t)->int(g1(x,t),r=1..infinity);

g3:=(x,t) -> (diff(g2(x,t),t)):


g4:=(x,t) -> (diff(g2(x,t),x,x)):


g5:=(x,t) -> ((1/2)*(g3(x,t)^2+g4(x,t)^2)):


E2:=t->(int(g5(x,t),x=0..100)):

evalf(E2(0));
Error, (in g1) numeric exception: division by zero
evalf(E2(1));
Error, (in g3) invalid input: diff received 1, which is not valid for its 2nd argument
plot(E2(t),t=0..20);

Best regards,

 

Hej guys,

in some of my Maple worksheets I'm using Maples fit-function to obtain a rational function fit to some data, as I'm interested in the zeros of enumerator and denominator, I chose my fit function accordingly. Afterwards I need to extract the results (mainly the zeros) and do some more calculation steps with them. When evaluating rational functions of high degree, I noticed that my way of extracting the results (I'm using patmatch) becomes increasingly slow up to the point where it takes a couple of minutes to extract 10 numbers.
E.g. the following minimal example (download link at the bottom) takes more than 20 minutes on my machine (Maple 18.01 Build ID 935137; Red Hat Version 6.6 running on system with an i5-3570, 8 GB of RAM). Additionally, the calculation requires an unreasonable amount of RAM.
I can work around the problem to some degree by extracting the leading coefficient beforehand, resulting in a substantial speed up, still I think that there might be some error in the code or my usage of patmatch.

Is there another way to extract these numbers in a similarly simple fashion?

Cheers,

Sören


restart

a pathmatch with 9 variables requires roughly 200 MB of memory and takes about 7 s to finish on an i5-3570 CPU:

p := (1+x)*(2+x)*(3+x)*(4+x)*(5+x)/((11+x)*(12+x)*(13+x)*(14+x));

(1+x)*(2+x)*(3+x)*(4+x)*(5+x)/((11+x)*(12+x)*(13+x)*(14+x))

(1)

pattern := (a__1::realcons+x)*(a__2::realcons+x)*(a__3::realcons+x)*(a__4::realcons+x)*(a__5::realcons+x)/((b__1::realcons+x)*(b__2::realcons+x)*(b__3::realcons+x)*(b__4::realcons+x)); patmatch(p, pattern, 'la'); assign(la)

(a__1::realcons+x)*(a__2::realcons+x)*(a__3::realcons+x)*(a__4::realcons+x)*(a__5::realcons+x)/((b__1::realcons+x)*(b__2::realcons+x)*(b__3::realcons+x)*(b__4::realcons+x))

 

true

(2)

a__1; a__2; a__3; a__4; a__5; b__1; b__2; b__3; b__4

1

 

2

 

3

 

4

 

5

 

11

 

12

 

13

 

14

(3)

a pathmatch with 9 variables requires roughly 2.2 GB (!) of memory and takes about 20 min (!) to finish on an i5-3570 CPU:

q := 9*p;

9*(1+x)*(2+x)*(3+x)*(4+x)*(5+x)/((11+x)*(12+x)*(13+x)*(14+x))

(4)

a__1 := 'a__1':

(a__1::realcons+x)*(a__2::realcons+x)*(a__3::realcons+x)*(a__4::realcons+x)*(a__5::realcons+x)*a::realcons/((b__1::realcons+x)*(b__2::realcons+x)*(b__3::realcons+x)*(b__4::realcons+x))

 

true

(5)

a;

1

 

1

 

2

 

3

 

4

 

5

 

11

 

12

 

13

 

14

(6)

NULL

Download patmatch-breakdown.mw

I'm trying to plot the region bounded by the coordinate planes, the plane z=2-y and the cylinder x=4-y^2

This is what I have so far.  I want to know how to get rid of the portions of the planes and cylinder that are not enclosing the region.

restart;

with(plots);

xmin := 0;
xmax := 4;
ymin := 0;
ymax := 2;
zmin := 0;
zmax := 2;

a := plot3d([2-y], x = xmin .. xmax, y = ymin .. ymax, orientation = [40, 70], transparency = 0, color = green, filled = false, title = "");
%;

b := implicitplot3d([z = 0, y = 0, x = 0], x = xmin .. xmax, y = ymin .. ymax, z = zmin .. zmax, transparency = .5, axes = normal);
%;
c := implicitplot3d([x = -y^2+4], x = xmin .. xmax, y = ymin .. ymax, z = zmin .. zmax, transparency = .5, filled = true, axes = normal, color = blue, orientation = [45, 35]);


display(a, b, c);

A duck, pursued by a fox, escapes to the center of a perfectly circular pond. The fox cannot swim, and the duck cannot take flight from the water. The fox is four times faster than the duck. Assuming the fox and duck pursue optimum strategies, is it possible for the duck to reach the edge of the pond and fly away without being eaten? If so, how?

http://www.crazyforcode.com/fox-duck-puzzle/

there is an animation here

https://www.youtube.com/watch?v=Zw9cHEnhzWo

wonder if the equations of motion can be derived usingg maple and an animaton...?

Hallo. I'd like to make a loop for two variables. Let say:

for i from 1..10, j from 1..10

How to do it?

Thanks.

Hi everyone:

I have two functions in terms of theta variable, how can I expressed function Y(X)?

X :=(theta)->cos(theta)+0.8e-1*cos(3.*theta)

Y :=(theta)->-sin(theta)+0.8e-1*sin(3.*theta)

I will earn Y(X) infact.

Thanks alot...

Mehran.

 

 

 

How to calculate the integral

(symbolically or/and numerically) with Maple?

 

1 2 3 4 5 6 7 Last Page 1 of 1043