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Dear friends,

I am reporting with a brief comment concerning the integral int(1/(1+x^a), x=0..infinity) with a>=2 a real number. This was evaluated here.

Now Maple 15 (X86 64 LINUX) will quite happily compute this in its most simple form involving the sine when a is not a positive integer or a rational number. If it is, however, a beta function term results,...

I'm trying to graph a contour map of this function: e^(y/x)

>with(plots)

>contourplot(e^(y/x),x=-3..3,y=-0.5..0.5)

I thought the contour map for this function would looks more like several lines intersects at the origin. But when I graph it on Maple, it doesn't looks like the graph I'm looking for.

Did I put in a wrong range?

Hi there i have function as:

f(B,F)=

where: F,B>0 and 

,

such that: 

h=B^2;

I need to plot the surface (contour plot) f(B,F) at 0 and -ve points i.e f(B,F)<0.

Thanks

Dear friends,

I will present a series of commands for you to ponder that should speak for themselves.

> q := n -> int(1/(1-2^n*exp(I*theta*n))^2*2*I*exp(I*theta), theta=0..2*Pi);
                            2 Pi
                           /
                          |          2 I exp(theta I)
               q := n ->  |      ------------------------ dtheta
                          |            n                2
                         /       (1 - 2  exp(theta n I...

Dear friends,

I ran into another problem while using Maple to do residue calculus. The following call

residue(1/x^(1/3)/(x^2+2*x*cos(phi)+1), x=-exp(I*phi));

returns zero -- it does not recognize the residue. On the other hand, if I do a subsitution like this

subs(x=-exp(I*phi), 1/x^(1/3)/(x^2+2*x*cos(phi)+1));

followed by

convert(%, trig); simplify(%);

then I get a divide by zero error, which shows that the...

Hello all,

I recently helped someone with a contour integration problem, you may find my calculation at the following link. It occurred to me to test this integral with Maple and Mathematica.

For example,

int(1/x^(1/3)/(x^2+2*x*cos(Pi/7)+1), x=0..infinity);

produces an unusable output from Mathematica. Maple is a little better,...

Is it possible to have a contour plot of an ode, 

restart:with(plots);alpha:=1:

de1:=alpha*diff(f(y),y$4)+(diff(f(y),y$2)*diff(f(y),y$3)^2+diff(f(y),y$4)*diff(f(y),y$2)^2);

with  such type of bcs?

bc1:= f(1+sin(x)) = .95, f(-.1-.1*sin(x)) = -.95, (D(f))(1+sin(x)) = -1, (D(f))(-.1-.1*sin(x)) = -1;

contourplot({de1,bc1}, [x,y, f(y)],x=1..10, y=1..10);

Thanks

Hi 

I want to make a 3D-plot with the style "surfacecontour". My question is: How do I define the number of contourlines? As I understand the default value is 10, but I only want 4. 

I hope you can help me!  

Hi there. 

I'm making some 2D contour plots and am desperate to know what the values are which are assigned to the different contour levels. e.g., a red band must be reading value 120 (say) and an orange one 80, but how can I get this and show it on a legend in the plot? It's crucial to the value of the plot. 

Many thanks for any help!

David

int(cos(a*z)/(z^2-4*z+8), z, method=contour)

why run in maple 15, unknown options method = contour

is it default to use contour?

but the result is the same as done by hand, i mean the answer from the book,

int(cos(a*z)/(z^2-4*z+8), z) return contain some Si  and Ci

Any Example can help see the difference between contour and simple integration?

int(XXXX, x, method = contour);

int (XXX, x)

which example can help to see the difference?

My contour of integration is a semi circle whose diameter rests on the imaginary axis from -ri to ri.  The arc of radius r is on the positive real axis going from -ri to ri.  On the curve I want to have directional arrows indicating that I am traversing this contour in the positive direction.  How do I create this figure in MAPLE?