restart;

assume(alph>0);

assume(alph,real);

f_exp:=exp(-alph*r^2);

ff_deriv:=simplify(r^2*f_exp^2);

ff:=simplify(int(ff_deriv,r=0..infinity));

It seems to understand what i'm trying to integrate but when I try and find ff it comes up with an awful expression full of erf functions and with a lim r--> infinity at the front. However on wolfram alpha I get the answer that I want: sqrt(pi/2)/(8*alpha^(3/2)).

I am trying to solve two differential equations numericaly:

I recently get a new macbook pro with retina display. Unfortunately Maple 16 seems to be not retina ready. Searching the net I found a tool called retinizer. Using it Maple 16 seems to be displaying a little better, but still the outputs of calculations looks blured. however, whenever certain texts are selected, the whole Maple window display becomes very sharp, so I guess Maple is somehow retina ready but this functionality is disabled by default. Checking the "Get Info" window...

hey all..
i want to plot graph for two tables.

Table1 shows value for crank nicolson method at different x and t 

t╲x  0.05	0.15	0.25	0.35	0.45	0.55	0.65	0.75	0.85

0.05	0.0855	0.2446	0.3708	0.4512	0.4815	0.4646	0.4609	0.3160	0.2001

0.15	0.0283	0.8214	0.1277	0.1607	0.1779	0.1776	0.1599	0.1267	0.0813
0.25	0.0112	0.0310	0.0474	0.0597	0.0662	0.0662	0.0597	0.0474	0.0306
0.35	0.0073	0.0128	0.0174	0.0222	0.0246	0.0246	0.0222	0.0175	0.0119

Hi 

In trying to solve:

 a := diff(u(t), t$2)+(p^2-I+t^2)*u(t) = 0;

I get the following solutions,              

sol1 := u(t) = _C1*WhittakerM(-1/4-(1/4*I)*p^2, 1/4, I*t^2)/sqrt(t)+_C2*WhittakerW(-1/4-(1/4*I)*p^2, 1/4, I*t^2)/sqrt(t)        

It should be possible to expand these into parabolic cylinder functions and but im not sure how, i would appreciate any help.

thanks

Hi I have three differential equations: 

u := diff(P(t), t) = -7*10^(-8)*P(t)*t/(P(t)*t+R(t))^(1/2),

diff(R(t), t) = 7*10^(-8)*t^2*P(t)/(P(t)*t+R(t))^(1/2)+600*(Z(t)^2-10^5*t^3*(1/(1.15*10^12))^(2/3)*e^(-1.15*10^12))/(t*(P(t)*t+R(t))^(1/2)),

diff(Z(t), t) = -4*10^5*(Z(t)^2-10^5*t^3*(1/(1.15*10^12))^(2/3)*e^(-1.15*10^12))/(t^2*(P(t)*t+R(t))^(1/2))

and i want to solve them with initial conditions:

initial := R(0) = 0, Z(0) = 0, P(0) = P;

Hello and thank you in advance,

I am used to Mathematica and am looking to switch, conditionals in Mathematica seem easy, like say

How do you replicate this in an easy to read way without lots of nested if statements?

hi 
am writing code and i need to  insert a column vector in maple  of n x 1 order. For specific n i know how to insert it but what if we want for n rows

May be some loop is used or some other commands.

Hi,

r:=[3,3,3,3,4,4,4,3,3,3,3,3,3,3,3,2,4,3,1];

What's the shortest way to create a frequency table from it?

Ie, tells me elements are 1,2,3,4

the corresponding counts are: 1,1,13 and 4

and then if it can return the number with highest counts: 3

Many thanks!

Casper

given differntial equation with boundary conditions.

{f'(x)}^2 - f(x)f''(x) = f'''(x) - 100 * f'(x) - 0.001 * [2 * f'(x) * f'''(x) - f(x) * f''''(x) - {f''(x)}^2] = 0

boundary conditions:

f(0)=0,  f''(0)=0,  f'(1)=1,  f(1)=0

how i will calculate this?

I want to find a triangle with the vertices A(x1, y1, z1), B(x2, y2, z2), C(x3, y3, z3) knowing that the point G(1,1,1) is centroid of the triagle ABC and x1, y1, z1, x2, y2, z2, x3, y3, z3 are integer numbers, but I can not find. How do I tell Maple to do that? 

Hellow, can any body give the suggestion regarding multiple plot in array

i have 

V:=(2*x+3*gamma)*y^2

d0:=subs(x=0.1,gamma1=0,V):
d1:=subs(x=0.1,gamma1=2,V):
d2:=subs(x=0.1,gamma1=4,V):

plot([d0,d1, d2], y=0..0.1,  legend = ["gamma = 0", "gamma= 2","gamma= 4"], titlefont = ["ROMAN", 15], labels = ["y ", "v"], labeldirections = ["horizontal", "vertical"], labelfont = ["HELVETICA", 10], linestyle = [solid, longdash,dashdot],color = [black, red,green], axesfont = ["HELVETICA", "ROMAN", 8], legendstyle = [font = ["HELVETICA", 9], location = bottom],axes=boxed);

and 

e0:=subs(x=0.5,gamma1=0,V):
e1:=subs(x=0.5,gamma1=2,V):
e2:=subs(x=0.5,gamma1=4,V):

plot([e0,e1, e2], y=0..0.1,  legend = ["gamma = 0", "gamma= 2","gamma= 4"], titlefont = ["ROMAN", 15], labels = ["y ", "v"], labeldirections = ["horizontal", "vertical"], labelfont = ["HELVETICA", 10], linestyle = [solid, longdash,dashdot],color = [black, red,green], axesfont = ["HELVETICA", "ROMAN", 8], legendstyle = [font = ["HELVETICA", 9], location = bottom],axes=boxed);

I want to display  this side by side  i,e set {do,d1,d2} and {eo,e1,e2} 

 thanks in advance

 exa.doc

Hi, I am trying to plot a solution curve on a vector field with an initial condition of y(0)=0 and I keep getting error messages. This is what I have so far:

with(DEtools); dfieldplot(diff(y(x), x) = x^2+y(x)^2-1, y(x), x = 0 .. 5, y = -1 .. 5, arrows = line, title = 'Slope*Field');

Thank you. 

Greetings,

I have a finite Fourier series of the form, Asin(x)cos(z) + Bsin(2x)cos(z) + Csin(3x)cos(2z) +... I would like to be able to extract the coefficients, A,B,C etc., that correspond to a specific mode. I have tried using the coeff and coeffs functions. They work for a one-dimensional Fourier series (i.e. if S= Asin(x) + Bsin(2x) + Csin(3x); is my series, then coeff(S,sin(2x) returns B). I cannot however get this to work for the 2-D case. Any suggestions?

Hello, I'm currently trying to approximate the solution of a PDE with Maple, but I'm having troubles with the boundarie conditions .
For instance, when I set : (dT/dr)(r=3,t) = 0 , everything works fine .

With (dT/dr)(r=3,t) = -T(r=3,t), it's still okay .
But if I set (dT/dr)(r=3) = -T(r=3,t)^4, Maple just ignores the second member and works as if it was 0 . There is no error notification, but I don't get a satisfying solution ..