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These are questions asked by jrive

I solve for a transfer function using Syrup, and want to operate on the Real part and Imagninary parts separately.  I've added "assumes" statements for every variable:  

assume(Rsrc, real);
assume(C1, real);
assume(Lp, real);
assume(C2, real);
assume(f, real);
assume(RL, real);
additionally(0 < Rsrc, 0 < C1, 0 < Lp, 0 < C2, 0 < RL, 0 < f);


When I then do something like :

instead of gettting just the real part of the expression, I get :


as if one of the variables was still not assumed to be Real.  I'm not sure where all the '~' are coming from ---is that the issue?


I apologize, I can't insert content for some reason..., although I can add the worksheeet.

After I define a Ckt (a ladder network) such as :

Ckt := [v1(4), R1(50) &+ L2(0.9600), Cp(0.8200), L1(0.5000) &+ R2(0.2000), RL(1.3430) &+ LL(0.1550)]

How would I then use the value of R1 as defined above, for example, in a subsequent calculation?

Assuming the results from Solve are in (sol,rest), how can I use R1 (defined in Ckts)as a variable  --something like:

P_R1_ave := (abs(eval(v[R1], rest))/sqrt(2))^2/Ckt[R1]



BTW, I can no longer "insert contents" .  I get the following error:

Maple Worksheet - Error

Failed to load the worksheet /maplenet/convert/t-match_impedance.mw .

I have no idea what may have changed --perhaps something on our server?



When I try to get the magnitude of the transfer function in the uploaded file, I get this error:

Error, invalid input: `simpl/abs` expects its 1st argument, a1, to be of type algebraic, but received [0.15000e8/(-0.2137457857e-6*f^2+(2.909554620*I)*f-(0.1565896548e-13*I)*f^3+0.152600e8)]

How do I get the magnitude and phase of this transfer function so I can plot it as a function of frequency, f?  If you can show me how to plot it, that would help a lot as well.


Thank you,

Maple Worksheet - Error

Failed to load the worksheet /maplenet/convert/temp.mw .

Download temp.mw

I have an assignment for Q that after subsequent other assignments and substitutions  results in 

-XC1*R1^2/((R1^2 + XC1^2)*(R1*XC1^2/(R1^2 + XC1^2) + 12960.54302))


when I type Q.


I would like to solve this for XC1, for values of Q that make  XC1 is real. 

How do I do this?  Can I rearrange this assignment?   

I guess I could do something like this:

eq1:= -XC1*R1^2/((R1^2 + XC1^2)*(R1*XC1^2/(R1^2 + XC1^2) + 12960.54302))


but Q as a function of XC1 is a derived from other relationships.


The worksheet probably makes what I'm asking more clear.    I was able to get the result, but I'm sure there is a better, more elegant  way to do what I needed to do...





Series-Parallel Conversion Equations as a function of Q


Q = Xs/Rs = Rp/Xp;


Rp := Rs*(Q^2 + 1);



Impedance Transpormation Equations

Rp := proc (Rs, Xs) options operator, arrow; (Rs^2+Xs^2)/Rs end proc

Xp := proc (Rs, Xs) options operator, arrow; (Rs^2+Xs^2)/Xs end proc

Rs := proc (Rp, Xp) options operator, arrow; Rp*Xp^2/(Rp^2+Xp^2) end proc

Xs := proc (Rp, Xp) options operator, arrow; Xp*Rp^2/(Rp^2+Xp^2) end proc


zL := 1.343+I*131.925




XL0p := Xp(Re(zL), Im(zL))



RLp := Rp(Re(zL), Im(zL))



QLp := RLp/XLp



XC2 := -XL0p



Q := XL1/(R1s+RLp)



R1s := Rs(R1, XC1)



XC1s := Xs(R1, XC1)



XL1 := -XC1s







tmp1 := solve(-XC1*R1^2/((R1^2+XC1^2)*(R1*XC1^2/(R1^2+XC1^2)+12960.54302)) = Tmp, XC1)

(-25000.*R1+(-0.3240135755e14*R1*Tmp^2+625000000.*R1^2-0.4199391884e18*Tmp^2)^(1/2))*R1/(Tmp*(50000.*R1+648027151.)), -1.*(25000.*R1+(-0.3240135755e14*R1*Tmp^2+625000000.*R1^2-0.4199391884e18*Tmp^2)^(1/2))*R1/(Tmp*(50000.*R1+648027151.))



{R1, Tmp, (-0.3240135755e14*R1*Tmp^2+625000000.*R1^2-0.4199391884e18*Tmp^2)^(1/2)}


simplify(solve(op(3, indets(numer(tmp1[1])))^2 > 0, Tmp, parametric))

piecewise(R1 <= -8398783768000/648027151, [[Tmp = Tmp]], R1 < 0, [[50*5^(1/2)*R1/(648027151*R1+8398783768000)^(1/2) < Tmp, Tmp < -50*5^(1/2)*R1/(648027151*R1+8398783768000)^(1/2)]], R1 = 0, [], 0 < R1, [[-50*5^(1/2)*R1/(648027151*R1+8398783768000)^(1/2) < Tmp, Tmp < 50*5^(1/2)*R1/(648027151*R1+8398783768000)^(1/2)]])




Download pi-filter_anal_copy.mw



Why won't Maple solve any of these inequalities for Q?

At first I tried solving the system of equations, but then I tried solving the inequalities individually for Q, and those too could not be solved by Maple.  What am I doing wrong?



assume(R1, real, R2, real, RL, real, XC1, real, XC2, real, XL1, real)

additionally(R1 > 0, R2 > 0, RL > 0, XC1 > 0, XC2 > 0, XL1 > 0)



eq3 := R1*(4*Q^2+1)-RL > 0

0 < R1*(4*Q^2+1)-RL


eq4 := 4*Q^2*R1*RL-(R1-RL)^2 >= 0

0 <= 4*Q^2*R1*RL-(R1-RL)^2


eq5 := Rs^2*(RL-R1)/Q^2+R1^2*RL > 0

0 < Rs^2*(RL-R1)/Q^2+RL*R1^2




sys1 := {eq3, eq4, eq5}

`assuming`([solve(sys1, {Q})], [R1 > RL])

`assuming`([solve(sys1, {Q})], [R1 < RL])

solve(sys1, {Q})

Warning, solutions may have been lost


solve(eq3, Q)

Warning, solutions may have been lost


solve(eq4, Q)

Warning, solutions may have been lost


solve(eq5, Q)

Warning, solutions may have been lost




Download pi-filter_anal_copy.mw

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