I want to get the result of multi-matrix multiply like followed below,

but error "final value in for loop must be numeric or character"

(*n is arbitrary and B[1],B[2],...,B[n] have been obtained*)

A:=LinearAlgebra:-IdentityMatrix(n);
#using the multiplication operation of matrix
for i from 1 to n do
   A:=LinearAlgebra:-Multiply(A,B[i]);
od:

return A

help me 

thanks

Hello

I have a loop with the do structure but there is an error in the loop .

how can I continue the loop by error or disregard it?

y(t) = _C1*exp(-1.*t)*sin(.57736*t)+_C2*exp(-1.*t)*cos(.57736*t)

The answer i got for a DE raised in mapleprime is given above.

What command do i write now to get a plot of the same?

Ramakrishnan V

Hey, how is can i see all the steps in maple? I would specially like to know it for differential equations.

For example we could use this one:

dl := 3*(diff(y(t), t, t))+6*(diff(y(t), t))+4*y(t) = 0 

Download problem.mw

This is part of a large simplifcation where lots of terms are being substituted. In two of those terms, it did not simplify as we would expect.

I think the main thing is trying to find a way to factor out the "2".

I could do this

> rule3:=w[1]/(1+1/exp(mu[p]))^2+(-w[1]+1)/(1+1/(exp(mu[p])*exp(eta[p2])))^2 = s[3];
>rule3:=2*rule3;

> rule3ne:=-(w[1]/(1+1/exp(mu[p]))^2+(-w[1]+1)/(1+1/(exp(mu[p])*exp(eta[p2])))^2) = -s[3];
> rule3ne:=2*rule3ne;

> applyrule(rule3,tmp[1]);
> applyrule(rule3ne,tmp[2]);

For this example, this works.

But I hope for a more generic approach.

Thanks,

casper

Hello, Im trying to do a jocobian

http://www.maplesoft.com/support/help/Maple/view.aspx?path=VectorCalculus/Jacobian

but when I try the example code

jacobian([rcos(t), rsin(t), r^2*t], [r, t])

i only get the output as 

jacobian([rcos(t), rsin(t), RandomMatrix(4, 4*density = .75, outputoptions = [shape = tringular*lowe])^2*t], [RandomMatrix(4, 4*density = .75, outputoptions = [shape = tringular*lowe]), t])

I want the output as a matrix as in the example url.

Thanks

a:=[1,2,3]:

b:=[1,2,3]:

evalb(a=b)    #The result is true

c:=Array([1,2,3]):

d:=Array([1,2,3]):

evalb(c=d)    #The result is false

This is Why?

I have the following system of non-linear equations and want to find their solutions experimenting with my parameters. I also want to restrict the solutions to be non-negative. I have done the following, but i am sure it exist a more efficient way. Can somone help on this? 

eqns := [A = (gr_c+delta)*kh^(1-alpha)/sav_rate, theta = Rk*(Rh-Rk)/(gamma*((Rh-Rk)^2+sigma^2)), theta = 1*1+kh, Rk = 1+rk-delta, Rh = 1+rh-delta, rk = A*alpha*kh^(alpha-1), rh = A*(1-alpha)*kh^alpha, sigma = sigmay/theta, varrho = Rap^((eps-1)*eps/(1-gamma)), Rap = Rk^(1-gamma)+(1-gamma)*Rk^(-gamma)*theta*(Rh-Rk)-.5*Rk^(-gamma-1)*gamma*(1-gamma)*theta^2*((Rh-Rk)^2+sigma^2), R = Rk+theta*(Rh-Rk), beta = ((1+gr_c)/R)^(1/eps)/varrho];
print(`output redirected...`); # input placeholder
[
[
[
[
[ (1 - alpha)
[ (gr_c + delta) kh
[A = ----------------------------,
[ sav_rate
[

Rk (Rh - Rk)
theta = ---------------------------, theta = 1 + kh,
/ 2 2\
gamma \(Rh - Rk) + sigma /

Rk = 1 + rk - delta, Rh = 1 + rh - delta,

(alpha - 1) alpha
rk = A alpha kh , rh = A (1 - alpha) kh ,

/(eps - 1) eps\
|-------------|
sigmay \ 1 - gamma /
sigma = ------, varrho = Rap , Rap =
theta

(1 - gamma) (-gamma)
Rk + (1 - gamma) Rk theta (Rh - Rk) - 0.5

(-gamma - 1) 2 / 2 2\
Rk gamma (1 - gamma) theta \(Rh - Rk) + sigma /,

/ 1 \]
|---|]
\eps/]
/1 + gr_c\ ]
|--------| ]
\ R / ]
R = Rk + theta (Rh - Rk), beta = ---------------]
varrho ]
]
vals := [alpha = .36, delta = 0.6e-1, sigmay = sqrt(0.313e-1), gamma = 3, eps = .5, gr_c = 0.2e-1, sav_rate = .23];
eval(eqns, vals);
print(`output redirected...`); # input placeholder
[
[
[
[ 0.64 Rk (Rh - Rk)
[A = 0.3478260870 kh , theta = -----------------------,
[ / 2 2\
[ 3 \(Rh - Rk) + sigma /

0.36 A
theta = 1 + kh, Rk = 0.94 + rk, Rh = 0.94 + rh, rk = ------,
0.64
kh

0.36 0.1769180601
rh = 0.64 A kh , sigma = ------------,
theta

0.1250000000
varrho = Rap ,

1 2 theta (Rh - Rk)
Rap = --- - -----------------
2 3
Rk Rk

2 / 2 2\
3.0 theta \(Rh - Rk) + sigma /
+ --------------------------------, R = Rk + theta (Rh - Rk),
4
Rk

2.000000000]
/1\ ]
1.0404 |-| ]
\R/ ]
beta = ---------------------]
varrho ]
]
eqns := [A = .3478260870*kh^.64, theta = (1/3)*Rk*(Rh-Rk)/((Rh-Rk)^2+sigma^2), theta = 1+kh, Rk = .94+rk, Rh = .94+rh, rk = .36*A/kh^.64, rh = .64*A*kh^.36, sigma = .1769180601/theta, varrho = Rap^.1250000000, Rap = 1/Rk^2-2*theta*(Rh-Rk)/Rk^3+3.0*theta^2*((Rh-Rk)^2+sigma^2)/Rk^4, R = Rk+theta*(Rh-Rk), beta = 1.0404*(1/R)^2.000000000/varrho];
print(`output redirected...`); # input placeholder
[
[
[
[ 0.64 Rk (Rh - Rk)
[A = 0.3478260870 kh , theta = -----------------------,
[ / 2 2\
[ 3 \(Rh - Rk) + sigma /

0.36 A
theta = 1 + kh, Rk = 0.94 + rk, Rh = 0.94 + rh, rk = ------,
0.64
kh

0.36 0.1769180601
rh = 0.64 A kh , sigma = ------------,
theta

0.1250000000
varrho = Rap ,

1 2 theta (Rh - Rk)
Rap = --- - -----------------
2 3
Rk Rk

2 / 2 2\
3.0 theta \(Rh - Rk) + sigma /
+ --------------------------------, R = Rk + theta (Rh - Rk),
4
Rk

2.000000000]
/1\ ]
1.0404 |-| ]
\R/ ]
beta = ---------------------]
varrho ]
]

solve(eqns, [Rk, Rh, varrho, Rap, beta, R, A, sigma, theta, rk, rh, kh]);

hello . i have a Partial differential equation i need some help with 

This is how it goes 

Hi everyone.

I always used simple command to plot graphs with parametric function:

> plot([seq([i, t, t=0..11-i], i=1..10)], thickness=3, color=blue); 

And I always obtained this:

But yesterday I installed second update for Maple 18, and now I get only error:

"Error, (in plot) invalid input: ToInert expects 1 or 2 arguments, but received 0"

What command I should use now?

I'd like to implement this in Maple, but being a newbie having hard time getting the syntax right:

This is what I tried:

a:='a';
f:= i->product( `if`(evalb(i<>j),(a-z(j))/(z(i)-z(j)),NULL),j=1..3);

but it is not skipping the i=j case, since when I call it with f(1) I get division by zero.

f(1);
Error, (in product) numeric exception: division by zero

Tried also

f:= i->product(`if`(evalb(not(i=j)),(a-z(j))/(z(i)-z(j)),NULL),j=1..3);
and few other things. I think the reason it fails is deeper than my level of Maple undertstanding.

How would you do this in Maple?

hello, I have a list of numbers, for example [1.2,5.6,7.2,0.5,-0.25,-4,6]. I would like to find the position of it in the list where the number is closest to zero. May I know if there is a function for this please? Thanks.

Hi,

I am interested to know if Abel equation of the form:

y'=a*y^3+(b*x+c)*y^2+d*y+(g*x+f)    where: a,b,c,d,g,f are constants. 

is belonging to any solvable classes? I noticed that most of the classes solved in the literature using invariant analysis has a rational coefficients in x and they do not have the full form as the one abov. Any suggestions for this ?

Regards

Hamada

AoA. How are you? Sir want to generate the attached square matrix for any value of M. Please help.

PhD (Scholar)
Department of Mathematics

AoA. How are you? I want to solve the following equation in one step and convenient way please help

psi(x):=Matrix(1,3,[x,x-1,x^(2)-x-1])

P := Matrix(3, 3, [1, 2, 1, 0, 1, 1, -1, 2, 3])

U := Matrix(3, 3, [a[1, 1], a[1, 2], a[1, 3], a[2, 1], a[2, 2], a[2, 3], a[3, 1], a[3, 2], a[3, 3]])

u := psi(x)^T*(P^2)^T*U*P^2*psi(t)-t*psi(x)^T*(P^2)^T*U*P^2*psi(1)-x*psi(1)^T*(P^2)^T*U*P^2*psi(t)+t*x*psi(1)^T*(P^2)^T*U*P^2*psi(1)

If you reduce my computational work or have any suggestion to solve please give.

PhD (Scholar)
Department of Mathematics