Which command is similar with IsNull function in VBA for assign 0 when detect not assigned

I want to find shortest time it takes particle to travel from point A(0,0) to B(1,1). I tried to solve this problem by using following code test.mw. I know that solution to this problem is cycloid and i already found its equations in parametric form.

My problem is that when i try to solve integral as a solution i receive Time := Float(infinity)*I.

Is there any way to get a numeric solution in Maple...

Are There  options to solve this problem?

I solved a PDE system and got module() export plot,plot3d,animate,value,settings; ... end module (Got ui(x,t) and ur(x,t))
And after it I try to solve the task
Xs := [0, .175, .789, 1.818, 3.287, 5.183];
n := 1;
interface(prettyprint = 1);
for t1 from 0 by 50 to 50 do
k1 := sol:-value(t1, output = listprocedure);

(b0*z^n+b1*z^(n-1) + ... + bn) / (a0*z^n+a1*z^(n-1)+... + a_n_minus_m*z^m)

expand
into

beta0 + beta1*(1/z) + ... + betam*(1/z^m) + beta_m_plus_1*r_m_plus_1(z)/a(z) + ... + betan*rn(z)/a(z)

> de := (1/4)*U*(diff(S(y)^4, `$`(y, 2))) = C*P1*((O*exp(G*y)-R*exp(J*y))/(P1*(exp(J*L)-exp(G*L)))+P2/P1);

print(`output redirected...`); # input placeholder
/ 2 \
1 | 2 / d \ 3 / d / d \\| /
- U |12 S(y) |--- S(y)| + 4 S(y) |--- |--- S(y)||| = C P1 |
4 \ \ dy / \ dy \ dy /// \

O exp(G y) - R exp(J y) P2\
------------------------ + --|

Help me please, How to get a spatial derivative?After solving a system of differential equations numerically, I got module.Help please, How can I find a  value of the first derivative? 
For example , after solving the PDE system, module() export plot,plot3d,animate,value,settings; ... end module
 So, I need to find diff(U(x,t),x) (for example x=0 and t=0) 

Hi,

Here an example of integral that Maple 17 cannot calculate (mean of standard Gumbel distribution)

> G:=int(x*exp(-x)*exp(-exp(-x)), x = -infinity .. infinity);

The result is known as the Euler-Mascheroni constant as shown by a numerical computation:

 > evalf(G);

0.5772156649

>  identify(%, extension = [gamma]);

gamma

> evalf(gamma)

0.5772156649

Also, it cannot compute the variance

hi

how r u

i am writting this commands for loop but its not working .

i want to write genralize matrix for M and K

> Digits := 100;
> n := 4;
> y := vector([1, 1, 1, 1, 1, 1, 1, 1]);
> results := matrix(n, 3);
> for i to n do a1h := Generate; M := Matrix([[2, 3, 0], [0, 1, 7], [3, 1, 2], [2, 1, 0], [0, 0, 1], [3, 7, 0], [1, 1, 1], [5, 1, 0]]); m := `.`(1/(`.`(M^%T, M)), M^%T); mm := `.`(m, y); results[i] := m^%T end do;

As described on the help page ?updates,Maple17,Performance, Maple 17 uses a new data structure for polynomials with integer coefficients. Our goal was to improve the performance and parallel speedup of polynomial algorithms that underpin much of the system and create a platform for large scale polynomial computations. Shown below is the new representation for 9xy³z

I have a set X={a,b,c,d,e} and a table as follows:

M[2]:=TABLE([e = {2,3}, a = 5, c = 1]);

Afterwards I want to add to this table all those elements (e.g. b={3,4} and d=4) of X which are unassigned in M[2]. How I can do this?

Please help me with transformation of the following expression:

> z:=abs(a)^2*b+abs(a)^2*c*conjugate(a);

where I want to derive

a*(conjugate(a)*b+conjugate(a)^2*c)

I try the following:

> z:=collect(z,a);

However it does't transformate z in any way.

In other words if I have
>z:=a*conjugate(a);

>z:=simplify(z);

I derive z=|a|^2. How to decompose z back into a*conjugate(a)?

Hello

I have a nasty definite integral to evaluate. I need to integrate w.r.t X[2] and leave the integrated expression as a function of   X[1].

The discretization is via the...

Let x, y, z be three nonnegative numbers and x^2 + y^2 + z^2 = 5. Find the minimum value of the expression

A = 1/2*x^2*y^2 + y^2*z^2 + z^2 *x^2 + 96/(x + y + z + 1).

How to find the minimum value of the expression?

Hello, I bring here a problem with maple where I make a definite integral and appear suddenly in the solution a "csgn".

Here is the integral :

(1)

V(z) = (int(int(theta*R*(H-p)/(H*(L*L)*sqrt((R*(H-p)/H)^2+(z-p)^2)), p = 0 .. z), o = 0 .. 2*Pi))/(4*Pi*epsilon)

But i want the solution for z where 0

(2)

V := proc (z) options operator, arrow; (1/4)*(int(int(theta*R*(H-p)/(H*L*L*sqrt(R^2*(H-p)^2/H^2+(z-p)^2)), p = 0 .. z), o = 0 .. 2*Pi))/(Pi*epsilon) end proc

I am trying to get Maple to calculate this for me:

Let X₁,X₂,...X₈₁ be a random sample from a distsribution (not necessarily normal) with mean µ=49 and standard deviation σ =8. Let ¯X = (1/81)* ∑_i=1⁸¹ * X_i

_{I need to find the mean, the standard deviation and the approximate distribition of ‾X,}

_{BTW, the 81 goes directly...}