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Hi,

 

I am having trouble in plotting the following surface (it is a quite complicated expression, but should be fine).

OwnSurface := [-Re(arctan(exp(I*Pi*(1/4))*(u^2+v^2)^(1/2)))-(1/2)*ln((1+(u^2+v^2)^2)^(1/2)), -arctan(1/((2*(u^2+v^2))^(1/2)-1))+7*Pi*(1/4), (1/8)*ln(u^2+v^2-(2*(u^2+v^2))^(1/2)+1)-(1/8)*ln(u^2+v^2+(2*(u^2+v^2))^(1/2)+1)-(1/4)*arctan(1/((2*(u^2+v^2))^(1/2)+1))+(1/4)*arctan(1/((2*(u^2+v^2))^(1/2)-1))];

plot3d(OwnSurface, u = -.4 .. .4, v = -.4 .. .4, labels = [x1, x2, x3]);

The only thing maple does is plotting a box with a diagonal line. How can I fix this?

 

I want to plot a curve of the form |z*e^(1-z)| = 1 (the Szego curve). I am not sure how to call complexplot() to make this happen. Just calling complexplot(abs(z*exp(1-z)) = 1) does not work, and I don't know what else to specify. Any help?

Spiral (equidistant) around the curve.  In this case, a spiral around the spiral.
So without any sense. 
spiral_around_curve.mw 
 
If we re-save the animation with the program Easy GIF Animator, its size is reduced by about 10 times, and sometimes much more.


Hello I have this assignment. I will translate it (because it is not english)

This is the assignment: [IMG]http://i68.tinypic.com/2cgoby9.jpg[/IMG]

(if u cant click on the above link, then u can see it here http://tinypic.com/view.php?pic=2cgoby9&s=9)

 

So it says:

-------

In an examination of young pigs' birth weight 853 newborn pigs were weighted. The weighting is shown in the table down below. 

 

[0,5-0,7] [0,7-0,9] [0,9-1,1] [1,1-1,3] [1,3-1,5] [1,5-1,7] [1,7-1,9] [1,9-2,1] [2,1-2,3] -> WEIGHT in kg

[26]            [43]       [102]       [145]        [171]      [196]     [119]       [42]          [9]      --> number of pigs

 

Draw a cumulative frequency curve of the weighting and determine the kvartils.

 

SO I usually do this in Maple, but this time I did a matrix but nothing happened.. I dont know how I should draw this curve? Help please. 

 

 

[IMG]http://i68.tinypic.com/2cgoby9.jpg[/IMG]

Hello,

I try to use a Catmull-Rom spline which has to match on several points.

I use a code extracted from the book "Geometry and curves with maple".

Here you can find an extract which is visible from google book :

I have slightly modified the initial procedure crom_2d. I didn't find the error in my procedure. May you help me to find the blocking point of my procedure ?

Here I attached my code:

CalculSplineMatmull-Rom.mw

Thank you for your help.

Suppose that we have the following curve on a unit sphere

r^2+z^2=1

phi=pi/3

-1<=z<=1

which is the implicit equation of a circle in "cylindrical coorinates" (r,phi,z) on the sphere.

How can I plot this curve without solving the implicit equation for r or z ?

Also, I don't want to make any parameterization.

Suppose I have the parametric equations of a circle

x=cost

y=sint

where t runs from 0 to 2*pi. How can I show the orientation of this parametric curve on a plot?

Hello,

I'm a very new beginner, and I have a question about getting the data of a curve from a JPG, without using manual measures an too getting more accurate datas.

I wish to fit the curve with a model. The JPG joined, from EU 2015, is about human thermoregulation. I still try to found a model with Mathematica but am uncertain seeing the result as illogic.

Did anyone write something to read curves from a JPG and get coordinates from these curves ? In the JPG, the curve is above, as an 'U'.

Thanks for your advice,

Milos.

How I can highlight p(1,1) and Q(2,4) on the curve f(x)=x^2?

I have the following code of a plot:

plot(
[
add(BS(bb[4], t, i, 3)*bb[1](i+1), i = 0..n),
add(BS(bb[4], t, i, 3)*bb[2](i+1), i = 0..n),
t = 0..1
],
color=red, axes=normal, scaling=constrained, numpoints=100, thickness=2
):

and I get the following error:

Error, (in BS) cannot determine if this expression is true or false: 0 <= t and t < .54901960784313725490196078431373

The problem is that, in the definition of BS, there are some conditions that depend on the variable t. It seems that Maple does not use a specific value of t when executing BS. My solution is to plot specific points, i.e., 

plot(
[
seq([add(BS(bb[4], h/5000, i, 3)*bb[1](i+1), i = 0..n),
add(BS(bb[4], h/5000, i, 3)*bb[2](i+1), i = 0..n)], h=0..5000)
],
color=red, axes=normal, scaling=constrained, numpoints=100, thickness=2
):

Can this be done in a more elegant way?

 

 

Hi, I'm new to Maple and have been trying to solve the below curve intersection. But the answer I am getting from Maple is incorrect and does not tally with the plot when drawn on excel, am I doing something wrong ???  (the intersect should be around x=93.9)

 

restart;
eq1:=y=86:
eq2:=y=-0.0000054527x^3+0.010903836x^2+0.0714244709x+74.18816:
sol:=solve({eq1,eq2},{x,y});

Let a piecewise-linear curve be defined by a listlist. For example,

LL := [[1.1, 2.04], [1.97, 4.04], [2.96, 2.97], [4.5, 6.4], [5.08, 7.21], [1.1, 4.04], [1.1, 2.04]]:
plot(LL);

How to find its natural parametrization in Maple? A procedure is desired. See Wiki for info.

Hi,

I have a small problem. I want to findout area under a curve. I got the plot from solving a partial differential equation. I want to find out area under the curve with out using interpolation. Are there any methods to find this.

 

here i enclose the method i have done.

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:
            
with(plots):
with(plottools):
ys := -0.4245333333e-1:
IBC1 := {u(x, 0) = 0, (D[1](u))(0, t) = 0, (D[1](u))(1, t) = c}:
S1 := pdsolve(PDE, IBC1, numeric, time = t, timestep = 0.1e-2);

p2 := S1:-plot(t = .2525);

p3 := getdata(p2);

p3[3]:
co:=CurveFitting[PolynomialInterpolation](p3[3], x):
Area := int(co, x = x[1] .. x[2]):

So this is the procedure i used to find out, but can there be any other procedure to findout area directly from hte solution of PDE.

Thanks.



 

Hello everybody,

 

my question concerns the visualizing possibilities of maple:

can maple visualize complex functions? (f(z): C->C)

If so, which possibilities do i have und what is the command for it? Maybe as a coulour diagram, as a vector field (f(x): R^2->R^2) , or as mapping of sets (e.g. curves, grids into new curves and curved lines)?

 

 

 

Thanks in advance

regards

Nikita

 

PS: I am using maple 18.

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