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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 

 

restart:
tmp:=Vector(
[
1+(-s[2]-s[4]+2*w[1]/(1+1/exp(mu[p]))^2+(2*(-w[1]+1))/(1+1/(exp(mu[p])*exp(eta[p2])))^2)*s[1]^3+(-s[2]+s[3])*s[1]^2-s[2]*s[1],

(s[2]+s[4]-2*w[1]/(1+1/exp(mu[p]))^2-(2*(-w[1]+1))/(1+1/(exp(mu[p])*exp(eta[p2])))^2)*s[1]^3
]
);

tmp := Vector(2, {(1) = 1+(-s[2]-s[4]+2*w[1]/(1+1/exp(mu[p]))^2+(-2*w[1]+2)/(1+1/(exp(mu[p])*exp(eta[p2])))^2)*s[1]^3+(-s[2]+s[3])*s[1]^2-s[2]*s[1], (2) = (s[2]+s[4]-2*w[1]/(1+1/exp(mu[p]))^2-(-2*w[1]+2)/(1+1/(exp(mu[p])*exp(eta[p2])))^2)*s[1]^3})

(1)

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

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

(2)

applyrule(rule3,tmp[1]);

1+(-s[2]-s[4]+2*w[1]/(1+1/exp(mu[p]))^2+2*(-w[1]+1)/(1+1/(exp(mu[p])*exp(eta[p2])))^2)*s[1]^3+(-s[2]+s[3])*s[1]^2-s[2]*s[1]

(3)

 

``

 

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.

Abel equation solution...

November 13 2014 Hamada 15

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

AoA. How are you? Hope you will be fine. I want write the following in Loop for any M

 

F[r,s]:=2^(k+2) m sqrt((c[r-1])/(c[s-1])) for r=2...(M+1), s=1..r-1 and (r+s)=odd;

F[r,s]:=0  otherwise

 

 

Novice question

I have two sets of inequalties:

s1:= (0<x, x<100)

s2:= (5<x, x<95)

I want each set to define a "range", so I can do set operations on the ranges. For example I want to determine that S2 is a subset of S1, S1 - S2 would give me (0<x, x<=5, 95<=x, x<100), S1 Union S2 = (0<x, x<100), etc

 

I assume these are simple things that can be done with Maple - but I am not sure how! Any suggestions?

I under stand how to do the calculus that's easy enough, but Maple is stil giving me a hard time.  The math par t is let the radius of the cylinder be r cms. 0<r<10 Then the height is 2 * Sqrt 100-r^2, the volume is V(r)=2PIr^2* sqrt 100-r^2 cm^3

Differentiante V(r) with respect to r we get V' (r) =2PIr^2(1/(2*sqrt(100-r^2)))(-2r) + (2PIsqrt(100-r^2))(2r)

V'(r)=(-2PIr^3 +4PIr(100-r^2))/sqrt (100-r^2)      V'(r)=2PIr(200-3r^2)/sqrt 100r^2         to find the critical point find the value of r when V(r) =0     2PI(200-3r^2)/sqrt 100-r^2 =0   2PIr(200-3r^2) = 0   r(200-3r^2)=0 

r=0 or 200-3r^2 =0     r=0 or r^2=200/3 r=sqrt(200/3) =10sqrt(2/3)   r is not in the interval so ignore it.  The critical point for 0<r<10 occurs at r = 10sqrt(2/3)       Since V'(r) >0 for 0<r<10sqroot(2/3) and V'(r) <0<10sqrt(2/3)<10

The dimensions are r=10sqrt(2/3) =8.16 cm and h=20/sqrt3 = 11.55 cm the volume is 4000PI/3*sqrt3=2418.4 cm^3

So how do I translate this into maple? Any help is greatly appreciated.

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