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Imaginary part of expression too difficult to calculate


Finding real and imaginary partsMathematica taking too long to calculate recursive functionComplex Plot with Imaginary Part encoded in colorGetting the real part of a expressionAbout Complex Numbers, Real part and Imaginary part (symbolic calculus)Bug in HypergeometricPFQRegularized?Equivalence of ComplexExpand and assuming real argumentsSummation of complex and complex conjugate - elimination of imaginary partHow to get the real part of a complex expressionRoots of an expression













2












$begingroup$


I am trying to calculate the imaginary part of a long expression. It's a long enough expression that Mathematica "hangs" when you run:



imFUN2 = ComplexExpand[Im[expression]];


Is there something I can do that can help speed things up?



Here is my full code:



expression = -((I Ωc (4 γa^4 + 16 Δd^4 - 48 Δd^3 Δp + 48 Δd^2 Δp^2 - 16 Δd Δp^3 + 4 I γa^3 
 (3 Δc + 6 Δd - 4 Δp - Δs) - 16 Δd^3 Δs + 32 Δd^2 Δp Δs - 16 Δd Δp^2 Δs - 4 Δd^2 Ωc^2 + 
 4 Δd Δp Ωc^2 + 4 Δd Δs Ωc^2 - 4 I dephasing Δd Ωd^2 + 12 Δd^2 Ωd^2 + 
 4 I dephasing Δp Ωd^2 - 24 Δd Δp Ωd^2 + 12 Δp^2 Ωd^2 - 8 Δd Δs Ωd^2 + 
 8 Δp Δs Ωd^2 - Ωc^2 Ωd^2 + Ωd^4 + 4 Δc^2 (4 Δd^2 - 4 Δd Δp + Ωd^2) - 
 2 γa^2 (4 Δc^2 + 26 Δd^2 + 10 Δp^2 + 2 Δc (13 Δd - 7 Δp - 2 Δs) + 
 6 Δp Δs - 2 Δd (18 Δp + 5 Δs) - Ωc^2 + 4 Ωd^2) + 4 Δc (8 Δd^3 - 4 Δd^2 (4 Δp + Δs) - 
 (4 Δp + Δs) Ωd^2 + Δd (8 Δp^2 + 4 Δp Δs - Ωc^2 + 4 Ωd^2)) - 2 I γa (24 Δd^3 + 
 4 Δc^2 (3 Δd - Δp) - 4 Δp^3 - 4 Δp^2 Δs - 4 Δd^2 (13 Δp + 4 Δs) + Δp Ωc^2 + Δs Ωc^2 - 
 2 I dephasing Ωd^2 - 10 Δp Ωd^2 - 3 Δs Ωd^2 + Δc (36 Δd^2 + 8 Δp^2 + 4 Δp Δs - 
 4 Δd (11 Δp + 3 Δs) - Ωc^2 + 7 Ωd^2) + Δd (32 Δp^2 + 20 Δp Δs - 3 Ωc^2 + 10 Ωd^2))))/
 ((γa + 2 I Δd) (2 γa^2 - 4 Δc^2 + 4 Δd Δp - 4 Δp^2 + 4 Δd Δs - 8 Δp Δs - 4 Δs^2 + 
 2 I γa (3 Δc + Δd - 3 (Δp + Δs)) + Δc (-4 Δd + 8 (Δp + Δs)) + Ωd^2) (4 I γa^3 (Δc - Δp) - 
 16 Δc^2 Δd Δp - 16 Δc Δd^2 Δp + 16 Δc^2 Δp^2 + 48 Δc Δd Δp^2 + 16 Δd^2 Δp^2 - 32 Δc Δp^3 -
 32 Δd Δp^3 + 16 Δp^4 - 4 Δc Δd Ωc^2 - 4 Δd^2 Ωc^2 + 8 Δc Δp Ωc^2 + 8 Δd Δp Ωc^2 - 
 8 Δp^2 Ωc^2 + Ωc^4 - 4 Δc^2 Ωd^2 - 4 Δc Δd Ωd^2 + 8 Δc Δp Ωd^2 + 8 Δd Δp Ωd^2 - 
 8 Δp^2 Ωd^2 - 2 Ωc^2 Ωd^2 + Ωd^4 + 2 γa^2 (-4 Δc^2 - 6 Δc Δd + 14 Δc Δp + 6 Δd Δp - 
 10 Δp^2 + Ωc^2 + Ωd^2) - 2 I γa (4 Δc^2 (Δd - 3 Δp) - 4 Δd^2 Δp + Δd (20 Δp^2 - 
 3 Ωc^2 - Ωd^2) + Δc (4 Δd^2 - 24 Δd Δp + 28 Δp^2 - 3 Ωc^2 - Ωd^2) + 4 Δp (-4 Δp^2 + 
 Ωc^2 + Ωd^2)) + 2 dephasing (2 γa^3 + 2 I γa^2 (2 Δc + 3 Δd - 5 Δp) + γa (-4 Δd^2 - 
 4 Δc (Δd - 3 Δp) + 20 Δd Δp - 16 Δp^2 + Ωc^2 + Ωd^2) + 2 I (4 Δd^2 Δp - 8 Δd Δp^2 +
 4 Δp^3 - Δp Ωc^2 + Δd Ωd^2 - Δp Ωd^2 + Δc (4 Δd Δp - 4 Δp^2 + Ωd^2)))))) /.
 γa -> 1, dephasing -> 10^-4;

imFUN2 = ComplexExpand[Im[expression]];





performance-tuning simplifying-expressions complex







share|improve this question











$endgroup$
















    2












    $begingroup$


    I am trying to calculate the imaginary part of a long expression. It's a long enough expression that Mathematica "hangs" when you run:



    imFUN2 = ComplexExpand[Im[expression]];


    Is there something I can do that can help speed things up?



    Here is my full code:



    expression = -((I Ωc (4 γa^4 + 16 Δd^4 - 48 Δd^3 Δp + 48 Δd^2 Δp^2 - 16 Δd Δp^3 + 4 I γa^3 
     (3 Δc + 6 Δd - 4 Δp - Δs) - 16 Δd^3 Δs + 32 Δd^2 Δp Δs - 16 Δd Δp^2 Δs - 4 Δd^2 Ωc^2 + 
     4 Δd Δp Ωc^2 + 4 Δd Δs Ωc^2 - 4 I dephasing Δd Ωd^2 + 12 Δd^2 Ωd^2 + 
     4 I dephasing Δp Ωd^2 - 24 Δd Δp Ωd^2 + 12 Δp^2 Ωd^2 - 8 Δd Δs Ωd^2 + 
     8 Δp Δs Ωd^2 - Ωc^2 Ωd^2 + Ωd^4 + 4 Δc^2 (4 Δd^2 - 4 Δd Δp + Ωd^2) - 
     2 γa^2 (4 Δc^2 + 26 Δd^2 + 10 Δp^2 + 2 Δc (13 Δd - 7 Δp - 2 Δs) + 
     6 Δp Δs - 2 Δd (18 Δp + 5 Δs) - Ωc^2 + 4 Ωd^2) + 4 Δc (8 Δd^3 - 4 Δd^2 (4 Δp + Δs) - 
     (4 Δp + Δs) Ωd^2 + Δd (8 Δp^2 + 4 Δp Δs - Ωc^2 + 4 Ωd^2)) - 2 I γa (24 Δd^3 + 
     4 Δc^2 (3 Δd - Δp) - 4 Δp^3 - 4 Δp^2 Δs - 4 Δd^2 (13 Δp + 4 Δs) + Δp Ωc^2 + Δs Ωc^2 - 
     2 I dephasing Ωd^2 - 10 Δp Ωd^2 - 3 Δs Ωd^2 + Δc (36 Δd^2 + 8 Δp^2 + 4 Δp Δs - 
     4 Δd (11 Δp + 3 Δs) - Ωc^2 + 7 Ωd^2) + Δd (32 Δp^2 + 20 Δp Δs - 3 Ωc^2 + 10 Ωd^2))))/
     ((γa + 2 I Δd) (2 γa^2 - 4 Δc^2 + 4 Δd Δp - 4 Δp^2 + 4 Δd Δs - 8 Δp Δs - 4 Δs^2 + 
     2 I γa (3 Δc + Δd - 3 (Δp + Δs)) + Δc (-4 Δd + 8 (Δp + Δs)) + Ωd^2) (4 I γa^3 (Δc - Δp) - 
     16 Δc^2 Δd Δp - 16 Δc Δd^2 Δp + 16 Δc^2 Δp^2 + 48 Δc Δd Δp^2 + 16 Δd^2 Δp^2 - 32 Δc Δp^3 -
     32 Δd Δp^3 + 16 Δp^4 - 4 Δc Δd Ωc^2 - 4 Δd^2 Ωc^2 + 8 Δc Δp Ωc^2 + 8 Δd Δp Ωc^2 - 
     8 Δp^2 Ωc^2 + Ωc^4 - 4 Δc^2 Ωd^2 - 4 Δc Δd Ωd^2 + 8 Δc Δp Ωd^2 + 8 Δd Δp Ωd^2 - 
     8 Δp^2 Ωd^2 - 2 Ωc^2 Ωd^2 + Ωd^4 + 2 γa^2 (-4 Δc^2 - 6 Δc Δd + 14 Δc Δp + 6 Δd Δp - 
     10 Δp^2 + Ωc^2 + Ωd^2) - 2 I γa (4 Δc^2 (Δd - 3 Δp) - 4 Δd^2 Δp + Δd (20 Δp^2 - 
     3 Ωc^2 - Ωd^2) + Δc (4 Δd^2 - 24 Δd Δp + 28 Δp^2 - 3 Ωc^2 - Ωd^2) + 4 Δp (-4 Δp^2 + 
     Ωc^2 + Ωd^2)) + 2 dephasing (2 γa^3 + 2 I γa^2 (2 Δc + 3 Δd - 5 Δp) + γa (-4 Δd^2 - 
     4 Δc (Δd - 3 Δp) + 20 Δd Δp - 16 Δp^2 + Ωc^2 + Ωd^2) + 2 I (4 Δd^2 Δp - 8 Δd Δp^2 +
     4 Δp^3 - Δp Ωc^2 + Δd Ωd^2 - Δp Ωd^2 + Δc (4 Δd Δp - 4 Δp^2 + Ωd^2)))))) /.
     γa -> 1, dephasing -> 10^-4;

    imFUN2 = ComplexExpand[Im[expression]];





    performance-tuning simplifying-expressions complex







    share|improve this question











    $endgroup$














      2












      2








      2





      $begingroup$


      I am trying to calculate the imaginary part of a long expression. It's a long enough expression that Mathematica "hangs" when you run:



      imFUN2 = ComplexExpand[Im[expression]];


      Is there something I can do that can help speed things up?



      Here is my full code:



      expression = -((I Ωc (4 γa^4 + 16 Δd^4 - 48 Δd^3 Δp + 48 Δd^2 Δp^2 - 16 Δd Δp^3 + 4 I γa^3 
       (3 Δc + 6 Δd - 4 Δp - Δs) - 16 Δd^3 Δs + 32 Δd^2 Δp Δs - 16 Δd Δp^2 Δs - 4 Δd^2 Ωc^2 + 
       4 Δd Δp Ωc^2 + 4 Δd Δs Ωc^2 - 4 I dephasing Δd Ωd^2 + 12 Δd^2 Ωd^2 + 
       4 I dephasing Δp Ωd^2 - 24 Δd Δp Ωd^2 + 12 Δp^2 Ωd^2 - 8 Δd Δs Ωd^2 + 
       8 Δp Δs Ωd^2 - Ωc^2 Ωd^2 + Ωd^4 + 4 Δc^2 (4 Δd^2 - 4 Δd Δp + Ωd^2) - 
       2 γa^2 (4 Δc^2 + 26 Δd^2 + 10 Δp^2 + 2 Δc (13 Δd - 7 Δp - 2 Δs) + 
       6 Δp Δs - 2 Δd (18 Δp + 5 Δs) - Ωc^2 + 4 Ωd^2) + 4 Δc (8 Δd^3 - 4 Δd^2 (4 Δp + Δs) - 
       (4 Δp + Δs) Ωd^2 + Δd (8 Δp^2 + 4 Δp Δs - Ωc^2 + 4 Ωd^2)) - 2 I γa (24 Δd^3 + 
       4 Δc^2 (3 Δd - Δp) - 4 Δp^3 - 4 Δp^2 Δs - 4 Δd^2 (13 Δp + 4 Δs) + Δp Ωc^2 + Δs Ωc^2 - 
       2 I dephasing Ωd^2 - 10 Δp Ωd^2 - 3 Δs Ωd^2 + Δc (36 Δd^2 + 8 Δp^2 + 4 Δp Δs - 
       4 Δd (11 Δp + 3 Δs) - Ωc^2 + 7 Ωd^2) + Δd (32 Δp^2 + 20 Δp Δs - 3 Ωc^2 + 10 Ωd^2))))/
       ((γa + 2 I Δd) (2 γa^2 - 4 Δc^2 + 4 Δd Δp - 4 Δp^2 + 4 Δd Δs - 8 Δp Δs - 4 Δs^2 + 
       2 I γa (3 Δc + Δd - 3 (Δp + Δs)) + Δc (-4 Δd + 8 (Δp + Δs)) + Ωd^2) (4 I γa^3 (Δc - Δp) - 
       16 Δc^2 Δd Δp - 16 Δc Δd^2 Δp + 16 Δc^2 Δp^2 + 48 Δc Δd Δp^2 + 16 Δd^2 Δp^2 - 32 Δc Δp^3 -
       32 Δd Δp^3 + 16 Δp^4 - 4 Δc Δd Ωc^2 - 4 Δd^2 Ωc^2 + 8 Δc Δp Ωc^2 + 8 Δd Δp Ωc^2 - 
       8 Δp^2 Ωc^2 + Ωc^4 - 4 Δc^2 Ωd^2 - 4 Δc Δd Ωd^2 + 8 Δc Δp Ωd^2 + 8 Δd Δp Ωd^2 - 
       8 Δp^2 Ωd^2 - 2 Ωc^2 Ωd^2 + Ωd^4 + 2 γa^2 (-4 Δc^2 - 6 Δc Δd + 14 Δc Δp + 6 Δd Δp - 
       10 Δp^2 + Ωc^2 + Ωd^2) - 2 I γa (4 Δc^2 (Δd - 3 Δp) - 4 Δd^2 Δp + Δd (20 Δp^2 - 
       3 Ωc^2 - Ωd^2) + Δc (4 Δd^2 - 24 Δd Δp + 28 Δp^2 - 3 Ωc^2 - Ωd^2) + 4 Δp (-4 Δp^2 + 
       Ωc^2 + Ωd^2)) + 2 dephasing (2 γa^3 + 2 I γa^2 (2 Δc + 3 Δd - 5 Δp) + γa (-4 Δd^2 - 
       4 Δc (Δd - 3 Δp) + 20 Δd Δp - 16 Δp^2 + Ωc^2 + Ωd^2) + 2 I (4 Δd^2 Δp - 8 Δd Δp^2 +
       4 Δp^3 - Δp Ωc^2 + Δd Ωd^2 - Δp Ωd^2 + Δc (4 Δd Δp - 4 Δp^2 + Ωd^2)))))) /.
       γa -> 1, dephasing -> 10^-4;

      imFUN2 = ComplexExpand[Im[expression]];





      performance-tuning simplifying-expressions complex







      share|improve this question











      $endgroup$




      I am trying to calculate the imaginary part of a long expression. It's a long enough expression that Mathematica "hangs" when you run:



      imFUN2 = ComplexExpand[Im[expression]];


      Is there something I can do that can help speed things up?



      Here is my full code:



      expression = -((I Ωc (4 γa^4 + 16 Δd^4 - 48 Δd^3 Δp + 48 Δd^2 Δp^2 - 16 Δd Δp^3 + 4 I γa^3 
       (3 Δc + 6 Δd - 4 Δp - Δs) - 16 Δd^3 Δs + 32 Δd^2 Δp Δs - 16 Δd Δp^2 Δs - 4 Δd^2 Ωc^2 + 
       4 Δd Δp Ωc^2 + 4 Δd Δs Ωc^2 - 4 I dephasing Δd Ωd^2 + 12 Δd^2 Ωd^2 + 
       4 I dephasing Δp Ωd^2 - 24 Δd Δp Ωd^2 + 12 Δp^2 Ωd^2 - 8 Δd Δs Ωd^2 + 
       8 Δp Δs Ωd^2 - Ωc^2 Ωd^2 + Ωd^4 + 4 Δc^2 (4 Δd^2 - 4 Δd Δp + Ωd^2) - 
       2 γa^2 (4 Δc^2 + 26 Δd^2 + 10 Δp^2 + 2 Δc (13 Δd - 7 Δp - 2 Δs) + 
       6 Δp Δs - 2 Δd (18 Δp + 5 Δs) - Ωc^2 + 4 Ωd^2) + 4 Δc (8 Δd^3 - 4 Δd^2 (4 Δp + Δs) - 
       (4 Δp + Δs) Ωd^2 + Δd (8 Δp^2 + 4 Δp Δs - Ωc^2 + 4 Ωd^2)) - 2 I γa (24 Δd^3 + 
       4 Δc^2 (3 Δd - Δp) - 4 Δp^3 - 4 Δp^2 Δs - 4 Δd^2 (13 Δp + 4 Δs) + Δp Ωc^2 + Δs Ωc^2 - 
       2 I dephasing Ωd^2 - 10 Δp Ωd^2 - 3 Δs Ωd^2 + Δc (36 Δd^2 + 8 Δp^2 + 4 Δp Δs - 
       4 Δd (11 Δp + 3 Δs) - Ωc^2 + 7 Ωd^2) + Δd (32 Δp^2 + 20 Δp Δs - 3 Ωc^2 + 10 Ωd^2))))/
       ((γa + 2 I Δd) (2 γa^2 - 4 Δc^2 + 4 Δd Δp - 4 Δp^2 + 4 Δd Δs - 8 Δp Δs - 4 Δs^2 + 
       2 I γa (3 Δc + Δd - 3 (Δp + Δs)) + Δc (-4 Δd + 8 (Δp + Δs)) + Ωd^2) (4 I γa^3 (Δc - Δp) - 
       16 Δc^2 Δd Δp - 16 Δc Δd^2 Δp + 16 Δc^2 Δp^2 + 48 Δc Δd Δp^2 + 16 Δd^2 Δp^2 - 32 Δc Δp^3 -
       32 Δd Δp^3 + 16 Δp^4 - 4 Δc Δd Ωc^2 - 4 Δd^2 Ωc^2 + 8 Δc Δp Ωc^2 + 8 Δd Δp Ωc^2 - 
       8 Δp^2 Ωc^2 + Ωc^4 - 4 Δc^2 Ωd^2 - 4 Δc Δd Ωd^2 + 8 Δc Δp Ωd^2 + 8 Δd Δp Ωd^2 - 
       8 Δp^2 Ωd^2 - 2 Ωc^2 Ωd^2 + Ωd^4 + 2 γa^2 (-4 Δc^2 - 6 Δc Δd + 14 Δc Δp + 6 Δd Δp - 
       10 Δp^2 + Ωc^2 + Ωd^2) - 2 I γa (4 Δc^2 (Δd - 3 Δp) - 4 Δd^2 Δp + Δd (20 Δp^2 - 
       3 Ωc^2 - Ωd^2) + Δc (4 Δd^2 - 24 Δd Δp + 28 Δp^2 - 3 Ωc^2 - Ωd^2) + 4 Δp (-4 Δp^2 + 
       Ωc^2 + Ωd^2)) + 2 dephasing (2 γa^3 + 2 I γa^2 (2 Δc + 3 Δd - 5 Δp) + γa (-4 Δd^2 - 
       4 Δc (Δd - 3 Δp) + 20 Δd Δp - 16 Δp^2 + Ωc^2 + Ωd^2) + 2 I (4 Δd^2 Δp - 8 Δd Δp^2 +
       4 Δp^3 - Δp Ωc^2 + Δd Ωd^2 - Δp Ωd^2 + Δc (4 Δd Δp - 4 Δp^2 + Ωd^2)))))) /.
       γa -> 1, dephasing -> 10^-4;

      imFUN2 = ComplexExpand[Im[expression]];





      performance-tuning simplifying-expressions complex




      performance-tuning simplifying-expressions complex






      share|improve this question















      share|improve this question













      share|improve this question




      share|improve this question








      edited 4 hours ago









      MarcoB

      37.5k556113




      37.5k556113










      asked 4 hours ago









      Steven SagonaSteven Sagona

      1866




      1866




















          1 Answer
          1






          active

          oldest

          votes


















          5












          $begingroup$

          Not an elegant solution but it works



          num = Numerator[expression];
          den = Denominator[expression];
          reNum, imNum = ComplexExpand[ReIm[num]];
          reDen, imDen = ComplexExpand[ReIm[den]];
          (imNum reDen - reNum imDen)/(reDen^2 + imDen^2)


          I think the problem is the denominator which is huge but I am surprised that my approach is not included in ComplexExpand






          share|improve this answer









          $endgroup$












          • $begingroup$
            This works for me, thanks. It is interesting though that you call ComplexExpand[ReIm[num]] inside your function. I guess I should always make sure I don't have fractions-inside-fractions before calling this. Also for completion it might be helpful for others to know that the real part is: (reNum reDen + imNum imDen)/(reDen^2 + imDen^2)
            $endgroup$
            – Steven Sagona
            3 hours ago










          Your Answer





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          1 Answer
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          1 Answer
          1






          active

          oldest

          votes









          active

          oldest

          votes






          active

          oldest

          votes









          5












          $begingroup$

          Not an elegant solution but it works



          num = Numerator[expression];
          den = Denominator[expression];
          reNum, imNum = ComplexExpand[ReIm[num]];
          reDen, imDen = ComplexExpand[ReIm[den]];
          (imNum reDen - reNum imDen)/(reDen^2 + imDen^2)


          I think the problem is the denominator which is huge but I am surprised that my approach is not included in ComplexExpand






          share|improve this answer









          $endgroup$












          • $begingroup$
            This works for me, thanks. It is interesting though that you call ComplexExpand[ReIm[num]] inside your function. I guess I should always make sure I don't have fractions-inside-fractions before calling this. Also for completion it might be helpful for others to know that the real part is: (reNum reDen + imNum imDen)/(reDen^2 + imDen^2)
            $endgroup$
            – Steven Sagona
            3 hours ago















          5












          $begingroup$

          Not an elegant solution but it works



          num = Numerator[expression];
          den = Denominator[expression];
          reNum, imNum = ComplexExpand[ReIm[num]];
          reDen, imDen = ComplexExpand[ReIm[den]];
          (imNum reDen - reNum imDen)/(reDen^2 + imDen^2)


          I think the problem is the denominator which is huge but I am surprised that my approach is not included in ComplexExpand






          share|improve this answer









          $endgroup$












          • $begingroup$
            This works for me, thanks. It is interesting though that you call ComplexExpand[ReIm[num]] inside your function. I guess I should always make sure I don't have fractions-inside-fractions before calling this. Also for completion it might be helpful for others to know that the real part is: (reNum reDen + imNum imDen)/(reDen^2 + imDen^2)
            $endgroup$
            – Steven Sagona
            3 hours ago













          5












          5








          5





          $begingroup$

          Not an elegant solution but it works



          num = Numerator[expression];
          den = Denominator[expression];
          reNum, imNum = ComplexExpand[ReIm[num]];
          reDen, imDen = ComplexExpand[ReIm[den]];
          (imNum reDen - reNum imDen)/(reDen^2 + imDen^2)


          I think the problem is the denominator which is huge but I am surprised that my approach is not included in ComplexExpand






          share|improve this answer









          $endgroup$



          Not an elegant solution but it works



          num = Numerator[expression];
          den = Denominator[expression];
          reNum, imNum = ComplexExpand[ReIm[num]];
          reDen, imDen = ComplexExpand[ReIm[den]];
          (imNum reDen - reNum imDen)/(reDen^2 + imDen^2)


          I think the problem is the denominator which is huge but I am surprised that my approach is not included in ComplexExpand







          share|improve this answer












          share|improve this answer



          share|improve this answer










          answered 4 hours ago









          HughHugh

          6,58421945




          6,58421945











          • $begingroup$
            This works for me, thanks. It is interesting though that you call ComplexExpand[ReIm[num]] inside your function. I guess I should always make sure I don't have fractions-inside-fractions before calling this. Also for completion it might be helpful for others to know that the real part is: (reNum reDen + imNum imDen)/(reDen^2 + imDen^2)
            $endgroup$
            – Steven Sagona
            3 hours ago
















          • $begingroup$
            This works for me, thanks. It is interesting though that you call ComplexExpand[ReIm[num]] inside your function. I guess I should always make sure I don't have fractions-inside-fractions before calling this. Also for completion it might be helpful for others to know that the real part is: (reNum reDen + imNum imDen)/(reDen^2 + imDen^2)
            $endgroup$
            – Steven Sagona
            3 hours ago















          $begingroup$
          This works for me, thanks. It is interesting though that you call ComplexExpand[ReIm[num]] inside your function. I guess I should always make sure I don't have fractions-inside-fractions before calling this. Also for completion it might be helpful for others to know that the real part is: (reNum reDen + imNum imDen)/(reDen^2 + imDen^2)
          $endgroup$
          – Steven Sagona
          3 hours ago




          $begingroup$
          This works for me, thanks. It is interesting though that you call ComplexExpand[ReIm[num]] inside your function. I guess I should always make sure I don't have fractions-inside-fractions before calling this. Also for completion it might be helpful for others to know that the real part is: (reNum reDen + imNum imDen)/(reDen^2 + imDen^2)
          $endgroup$
          – Steven Sagona
          3 hours ago

















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