Greetings!
"Mike Thomas" writes:
> Hi all.
>
> At the end of this message is a batch file defining and attenpting to solve
> a system of two non-linear equations. Also included is the result of
> attempting to run that batch file on Windows Maxima 5.9.1.
>
> Am I being overly optimistic in hoping that Maxima would solve those
> equations or is this a bug, (perhaps GCL/Windows specific)?
>
> Note that the variable eq1 has it's name altered to EQ1 at input.
>
> =========================================================
>
> %i26) DISPLAY2D : FALSE
> (%o26) FALSE
> (%i27) K_1:37
> (%o27) 37
> (%i28) mu_1:44
> (%o28) 44
> (%i29) alpha_1:1
> (%o29) 1
> (%i30) x_1:0.7
> (%o30) 0.7
> (%i31) K_2:2.25
> (%o31) 2.25
> (%i32) mu_2:0
> (%o32) 0
> (%i33) alpha_2:1
> (%o33) 1
> (%i34) x_2:0.29
> (%o34) 0.29
> (%i35) K_3:2.25
> (%o35) 2.25
> (%i36) mu_3:0
> (%o36) 0
> (%i37) alpha_3:0.01
> (%o37) 0.01
> (%i38) x_3:0.01
> (%o38) 0.01
> (%i39) beta_sc:mu_sc*(mu_sc+3*K_sc)/(4*mu_sc+3*K_sc)
> (%o39) mu_sc*(mu_sc+3*K_sc)/(4*mu_sc+3*K_sc)
> (%i40) zeta_sc:mu_sc*(8*mu_sc+9*K_sc)/(6*(2*mu_sc+K_sc))
> (%o40) mu_sc*(8*mu_sc+9*K_sc)/(6*(2*mu_sc+K_sc))
> (%i41) P1:(4*mu_sc/3+K_sc)/(4*mu_sc/3+K_1)
> (%o41) (4*mu_sc/3+K_sc)/(4*mu_sc/3+37)
> (%i42) Q1:(zeta_sc+mu_sc)/(zeta_sc+mu_1)
> (%o42) (mu_sc*(8*mu_sc+9*K_sc)/(6*(2*mu_sc+K_sc))+mu_sc)
> /(mu_sc*(8*mu_sc+9*K_sc)/(6*(2*mu_sc+K_sc))+44)
> (%i43) P2:(4*mu_sc/3+K_sc)/(4*mu_sc/3+K_2)
> (%o43) (4*mu_sc/3+K_sc)/(4*mu_sc/3+2.25)
> (%i44) Q2:(zeta_sc+mu_sc)/(zeta_sc+mu_2)
> (%o44) 6*(2*mu_sc+K_sc)*(mu_sc*(8*mu_sc+9*K_sc)/(6*(2*mu_sc+K_sc))+mu_sc)
> /(mu_sc*(8*mu_sc+9*K_sc))
> (%i45) P3:(4*mu_3/3+K_sc)/(%PI*alpha_3*beta_sc+4*mu_3/3+K_3)
> (%o45) K_sc/(0.01*%PI*mu_sc*(mu_sc+3*K_sc)/(4*mu_sc+3*K_sc)+2.25)
> (%i46) Q3:(2*(2*(mu_sc+mu_3)/3+K_3)/(%PI*alpha_3*beta_sc+4*mu_3/3+K_3)
> +8*mu_sc/(%PI*alpha_3*(2*beta_sc+mu_sc)+4*mu_3)+1)
> /5
> (%o46) (2*(2*mu_sc/3+2.25)/(0.01*%PI*mu_sc*(mu_sc+3*K_sc)/(4*mu_sc+3*K_sc)
> +2.25)
> +800.0*mu_sc/(%PI*(2*mu_sc*(mu_sc+3*K_sc)/(4*mu_sc+3*K_sc)+mu_sc))+1)
> /5
> (%i47) EQ1:x_3*(K_3-K_sc)*P3+x_2*(K_2-K_sc)*P2+x_1*(K_1-K_sc)*P1 = 0
> (%o47) 0.01*(2.25-K_sc)*K_sc/(0.01*%PI*mu_sc*(mu_sc+3*K_sc)/(4*mu_sc+3*K_sc)
> +2.25)
> +0.7*(37-K_sc)*(4*mu_sc/3+K_sc)/(4*mu_sc/3+37)
> +0.29*(2.25-K_sc)*(4*mu_sc/3+K_sc)/(4*mu_sc/3+2.25)
> = 0
> (%i48) eq2:x_3*(mu_3-mu_sc)*Q3+x_2*(mu_2-mu_sc)*Q2+x_1*(mu_1-mu_sc)*Q1 = 0
> (%o48) -0.002*mu_sc
> *(2*(2*mu_sc/3+2.25)/(0.01*%PI*mu_sc*(mu_sc+3*K_sc)
> /(4*mu_sc+3*K_sc)
> +2.25)
> +800.0*mu_sc/(%PI*(2*mu_sc*(mu_sc+3*K_sc)/(4*mu_sc+3*K_sc)
> +mu_sc))+1)
> +0.7*(44-mu_sc)*(mu_sc*(8*mu_sc+9*K_sc)/(6*(2*mu_sc+K_sc))+mu_sc)
> /(mu_sc*(8*mu_sc+9*K_sc)/(6*(2*mu_sc+K_sc))+44)
> -1.74*(2*mu_sc+K_sc)*(mu_sc*(8*mu_sc+9*K_sc)/(6*(2*mu_sc+K_sc))+mu_sc)
> /(8*mu_sc+9*K_sc)
> = 0
> (%i49) ALGSYS([EQ1,eq2],[K_sc,mu_sc])
> Maxima encountered a Lisp error:
>
> Error in CATCH [or a callee]: Bind stack overflow.
>
> Automatically continuing.
> To reenable the Lisp debugger set *debugger-hook* to nil.
> =========================================================
If this is not some infinite loop error in maxima, you might get
further with :lisp (setq si::*multiply-stacks* 2)
Take care,
--
Camm Maguire camm@enhanced.com
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"The earth is but one country, and mankind its citizens." -- Baha'u'llah