Imaginary part of expression too difficult to calculate












3












$begingroup$


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]];









share|improve this question











$endgroup$

















    3












    $begingroup$


    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]];









    share|improve this question











    $endgroup$















      3












      3








      3





      $begingroup$


      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]];









      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






      share|improve this question















      share|improve this question













      share|improve this question




      share|improve this question








      edited 8 hours ago









      MarcoB

      37.5k556113




      37.5k556113










      asked 8 hours ago









      Steven SagonaSteven Sagona

      1917




      1917






















          1 Answer
          1






          active

          oldest

          votes


















          6












          $begingroup$

          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
            7 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









          6












          $begingroup$

          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
            7 hours ago
















          6












          $begingroup$

          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
            7 hours ago














          6












          6








          6





          $begingroup$

          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 8 hours ago









          HughHugh

          6,59421945




          6,59421945












          • $begingroup$
            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
            7 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
            7 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
          7 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
          7 hours ago


















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