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Re: Local Variables in Proc

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"Thomas D. Dean" <tomdean@speakeasy.org> writes:

> See below.
>
> I want to make a group of variables in a proc local.
>
> But, I call Syrup[Solve] and the variables are not resolved.
>
> How do I do this?
>
> Tom Dean
>
> ## simulate the source for the ideal loop,
> ## http://www.vlf.it/feletti2/idealloop.html
> ##
> ## restart;
> with(Syrup): with(ScientificConstants):
> loop := proc(wire_sel)
> description "Calculations on a loop antenna designed for VLF applications."
> "  The argument wire_sel is the index into the wire constants vectors."
> "  The return value, vout, contains a variable f, the frequency."
> "  ";
> local A, R, gauge, Dia, len_kg, dia, N, L, Cl;
> local Cs, Rin, Cin, Rlk, mu, Z, Clight, lambda, h;
> local rho, B, omega, Vsource, ckt, volts, others, vout;
> local resist;
> # loop dimensions
>     A   :=(475/10*Unit('cm'))^2;
>     R   :=60;
>     gauge  := <  26,   24,   22,   20,   18>;
>     Dia    := < 410,  510,  640,  800, 1000>;
>     len_kg := <8875, 5485, 3464, 2167, 1366> / 10;
>     resist := 348/10*len_kg/1000; ## ohms/km * m / (m/km)
>     ##wire_sel := 4;
>     dia := Dia[wire_sel]*Unit('um');
>     N   := floor(simplify(len_kg[wire_sel]*Unit('m') / 4 / sqrt(A)));
>     L   := 80*Unit('mH');
>     Cl  :='Cl';  ## prevent errors
>     Cl  := 235*Unit('pF');
>     Cs  :='Cs';  ## prevent errors
>     Cs  := 510*Unit('pF');
>     Rin := 75/10*Unit('kOmega');  ## ad797 differential input stage
>     Cin := 20*Unit('pF');         ## ad797 differential input stage
>     Rlk := 100*Unit('MOmega');    ## ad797 differential input stage
> ##
> ## derived values from physical constants
>     mu[0]  := GetValue(Constant('mu[0]'))*GetUnit(Constant('mu[0]'));
>     mu[r]  := 1;
>     Z[0]   := GetValue(Constant('Z[0]'))*GetUnit(Constant('Z[0]'));
>     Clight := GetValue(Constant('c'))*GetUnit(Constant('c'));
>     lambda := Clight/(f*Unit('Hz'));
>     h[e]   := simplify(2*Pi*N*A*mu[r]/lambda);
>     rho    := 17240*10^(-12)*Unit('Omega*m');
> ## radiation resistance
>     R[rad] := simplify(Z[0] * 2/3 * Pi * (h[e]/lambda)^2);
> ## AC resistance
>     R[ac]  := simplify(4 * N * sqrt(A) / (Pi * dia) *
> sqrt(Pi*mu[0]*f*Unit('Hz')
> *rho));
> ## dc resistance
>     R[dc]  := resist[wire_sel]; ##
> simplify(4*N*sqrt(A)/((Pi*dia^2)/4)*rho);
> ## source controlled source
> ## Z[0] :=GetValue(Constant('Z[0]'));
> ## mu[0]:=GetValue(Constant('mu[0]'));
> ## B is in tesla (or Wb, H is A/m, B = mu[0] * mu[r] * H
> ## use 1pT as source field strength
> ## B:=convert(1,'units','pT','kg/(A*s^2)');
> ## H:=solve(B=mu[0]*GetUnit(Constant('mu[0]'))*mu[r]*'H','H');
> ## H:=1e-12*Unit('T')/mu[0]/GetUnit(Constant('mu[0]'));
> ##
> ## Volts = meter^2 * kg / (s^3 * A)
> ## to get from tesla to volts: simplify(Unit('Hz')*Unit('m^2')*Unit('pT'));
>     B     :=1*Unit('pT');
> ## or, freq * area * tesla
>     omega :=2*Pi*f*Unit('Hz');
>
> ## loop voltage source
>     Vsource := simplify(omega*A*N*B);
>
>     ckt := "* Ideal Loop Source\n"
>     "Vloop    1 2 map(convert,Vsource,unit_free)\n"
>     "Lloop    2 3 map(convert,L,unit_free)\n"
>     "Rac      3 4 map(convert,R[ac],unit_free)\n"
>     "Rdc      4 5 map(convert,R[dc],unit_free)\n"
>     "Rrad     5 6 map(convert,R[rad],unit_free)\n"
>     "Cloop    6 1 map(convert,Cl,unit_free)\n"
>     "Cshield1 1 0 map(convert,Cs/2,unit_free)\n"
>     "Cshield2 6 0 map(convert,Cs/2,unit_free)\n"
>     "Rload    6 1 map(convert,Rin,unit_free)\n"
>     "Cload    6 1 map(convert,Cin,unit_free)\n"
>     "Rleak    1 0 map(convert,Rlk,unit_free)\n"
>     ".end";
> #
>     volts,others:=Solve(ckt,returnall);
>     assign(volts);
>     vout:=eval(v[6]-v[1],s=I*map(convert,omega,unit_free));
>     vout:=simplify(vout);
>     print(Rlk);
>     evala(vout);
> end proc:
>
> vout := loop(4):

What problem are you seeing?  The procedure runs here, but
I'm using a developmental version of Syrup.  It returns

 100 [M&Omega;]

-- 
Joe Riel

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Local Variables in Proc "Thomas D. Dean" <tomdean@speakeasy.org> - 2015-06-25 09:29 -0700
  Re: Local Variables in Proc Joe Riel <joer@san.rr.com> - 2015-07-03 13:04 -0700
    Re: Local Variables in Proc "Thomas D. Dean" <tomdean@speakeasy.org> - 2015-07-07 02:58 -0700
      Re: Local Variables in Proc Joe Riel <joer@san.rr.com> - 2015-07-07 09:54 -0700

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