pik1432

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These are questions asked by pik1432

Hello there, 

Is there any chance to ask if there is a way to simplify the numeric outcome from an operation?

Here is what I've been trying:

restart;

with(LinearAlgebra):

interface(imaginaryunit=j):

Amat := Matrix(2, 2, [[-0.1428571428*K__D, -0.1081971238], [376.9911185, 0]]);

Matrix(2, 2, {(1, 1) = -.1428571428*`#msub(mi("K"),mi("D",fontstyle = "normal"))`, (1, 2) = -.1081971238, (2, 1) = 376.9911185, (2, 2) = 0})

(1)

Eigenvalues(Amat);

Vector(2, {(1) = -0.7142857140e-1*`#msub(mi("K"),mi("D",fontstyle = "normal"))`+0.2000000000e-9*sqrt(0.1275510203e18*`#msub(mi("K"),mi("D",fontstyle = "normal"))`^2-0.1019733868e22), (2) = -0.7142857140e-1*`#msub(mi("K"),mi("D",fontstyle = "normal"))`-0.2000000000e-9*sqrt(0.1275510203e18*`#msub(mi("K"),mi("D",fontstyle = "normal"))`^2-0.1019733868e22)})

(2)

Desired := sqrt((2.000000000*10^(-10))^2 * (1.275510203*10^17*K__D^2 - 1.019733868*10^21));

(0.5102040812e-2*K__D^2-40.78935472)^(1/2)

(3)

 


I tried to simplify the Eigen values, to make them in the formality of the 'Desired' numerical expression, but no success yet. 

Thank you, 

Download Q20230110_m1.mw

Hello there, 

Is there any chance to see that the 'eq_5_22_desired' expression shown below can be derived from a collection of the commands. similar to what's given in the 'eq_5_22a'? In other words, is it possible to make Maple aware of the point that 'L__ad/(L__ad + L__fd)' can be interpreted as 'L__ad*L__fd/(L__ad + L__fd) * 1/L__fd'?

restart;

with(LinearAlgebra):

interface(imaginaryunit=j):

eq_5_22 := Psi__ad = -L__ad*L__fd*i__d*1/(L__ad + L__fd) + L__ad*Psi__fd*1/(L__ad + L__fd);

Psi__ad = -L__ad*L__fd*i__d/(L__ad+L__fd)+L__ad*Psi__fd/(L__ad+L__fd)

(1)

eq_5_23x := L__ad__p = 1 / (1/L__ad + 1/L__fd);

L__ad__p = 1/(1/L__ad+1/L__fd)

(2)

eq_5_23 := L__ad__p = evala(rhs(eq_5_23x));

L__ad__p = L__ad*L__fd/(L__ad+L__fd)

(3)

eq_5_22a := Psi__ad = collect(expand(solve(eq_5_18x, Psi__ad)), rhs(eq_5_23)); # error

Error, invalid input: expand expects 1 argument, but received 0

 

eq_5_22_desired := Psi__ad = -L__ad__p*i__d + L__ad__p*Psi__fd/L__fd;

Psi__ad = -L__ad__p*i__d+L__ad__p*Psi__fd/L__fd

(4)

 

Download Q20220812.mw

Hello there, 

Would you allow me to ask this question?

Is there any way to apply 'collect' command using a term by multiplication of variables?

The following worksheet shows an example. What I wanted to see is the 'desired' expression, while multiple attempts with 'collect' command failed. 


 

restart;

eq_e5_10z := Psi[q0]*Delta*delta = 1/(omega[0])*p(Delta*Psi[q])+Delta*Psi[d]+Psi[d0]*1/(omega[0])*p(Delta*delta);

Psi[q0]*Delta*delta = p(Delta*Psi[q])/omega[0]+Delta*Psi[d]+Psi[d0]*p(Delta*delta)/omega[0]

(1)

eq_e5_10za := Delta*Psi[d] = Psi[q0]*Delta*delta - op(1, rhs(eq_e5_10z)) - op(3, rhs(eq_e5_10z));

Delta*Psi[d] = Psi[q0]*Delta*delta-p(Delta*Psi[q])/omega[0]-Psi[d0]*p(Delta*delta)/omega[0]

(2)

eq_e5_10zb := subs({p(Delta*Psi[q])=0}, eq_e5_10za);

Delta*Psi[d] = Psi[q0]*Delta*delta-Psi[d0]*p(Delta*delta)/omega[0]

(3)

collect(rhs(eq_e5_10zb), {Delta*delta});# error

Error, (in collect) cannot collect Delta*delta

 

collect(rhs(eq_e5_10zb), [Delta*delta]);# error

Error, (in collect) cannot collect Delta*delta

 

collect(rhs(eq_e5_10zb), [Delta, delta]);# did not work  

Psi[q0]*Delta*delta-Psi[d0]*p(Delta*delta)/omega[0]

(4)

Desired := (psi__q0 - psi__d0*p/omega__0)*(Delta*delta);

(psi__q0-psi__d0*p/omega__0)*Delta*delta

(5)

 


 

Download Q20220602.mw

Hello there, 

Would you allow me to ask this one question?

Is it possible to apply diffop2de() to three different functions in a single expression? For example, the attached worksheet shows an expression, 'eq_e5_9', where three time domain function derivatives are defined, D*Delta__delta(t), D*Delta__psi__d(t) and D*Delta__psi__q(t). However, once 'diffop2de(eq_e5_9, f(t))' is applied, none of them gets propely unrolled (e.g, D*Delta__delta(t)becomes d/dt*Delta__delta(t))

Besides, this is my third time attempting to post a question. The first one got disappeared with no sign, the second one came out with a site error message. 

In Kwon Park 

 

Download Q20220425.mw

Hello all, 

Is there any chance to ask these two questions?

1) What would be the way to pick up the result from 'LPSolve' command? I thought that the command would overlay the result to the input matrix, but I was wrong. 

2) This question is not related to Maple, but I saw that the transportation problem described in the attached worksheet has multiple solutions. In other words, the solution that came up with 'LPSolve' command was different from what the textbook presented, but both of them were legitimate solutions. Therefore, I'm wondering if there is a way to test the uniqueness of the solution. 

In Kwon Park 

Q20220416.mw

 

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