How do I optimize my Python code for balancing a centrifuge with a given input size?











up vote
0
down vote

favorite












So, the problem is, given an input N as the size of a centrifuge, I need to find out the number of balanced configurations. The full description is here.




Centrifuge is a piece of equipment that puts multiple test tubes in rotation at very high speeds. It consists of a cylindrical rotor with holes situated evenly along the circumference of the rotor.
Because the device is operating at high speeds, the center of mass of all tubes must coincide with the center of the rotor. We assume all tubes have the same mass.



For the sake of simplicity, we also assume that tubes are point masses, fixed firmly to the rotor. All at the same distance from the center. You may safely assume the (x,y) coordinates of tube k are $Rsin a, Rcos a$, where $a = 2pifrac{k}{n}$



The problem is: Given a centrifuge with N holes and K tubes, is it possible to balance it?



example 1: given N = 6 possible values for K are 2,3,4,6.



example 2: given N = 12, it is possible to balance 5 tubes: put 3 evenly dispersed (every 4th hole), then find a pair of opposite unoccupied holes and insert remaining 2 tubes there.



example 3: given N = 10, it is impossible to balance 7 tubes: put 5 evenly dispersed, and there's no opposite unoccupied holes left!




This is my code:



import numpy as np

N=int(input())
angle = 2*np.pi/N
z = complex(np.cos(angle), np.sin(angle))


import itertools
combs =
lst = range(1,N)
for i in range(2, N-1):
combs.append(i)
els = [list(x) for x in itertools.combinations(lst, i)]
combs.append(els)


count=1
lis =
while count<=len(combs):
for a in range(len(combs[count])):
s=0
for b in range(len(combs[count][a])):
s+=z**combs[count][a][b]
if abs(s)<1e-10:
lis.append(combs[count][a])
count+=2


lengths =
for i in lis:
if len(i) not in lengths:
lengths.append(len(i))

print(len(lengths)+1)


The code works fine, but slows down after input size of above 20, and is practically unusable after the input grows to 50 or above, due to the for loops. How do I optimize it?










share|improve this question









New contributor




Kristada673 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
























    up vote
    0
    down vote

    favorite












    So, the problem is, given an input N as the size of a centrifuge, I need to find out the number of balanced configurations. The full description is here.




    Centrifuge is a piece of equipment that puts multiple test tubes in rotation at very high speeds. It consists of a cylindrical rotor with holes situated evenly along the circumference of the rotor.
    Because the device is operating at high speeds, the center of mass of all tubes must coincide with the center of the rotor. We assume all tubes have the same mass.



    For the sake of simplicity, we also assume that tubes are point masses, fixed firmly to the rotor. All at the same distance from the center. You may safely assume the (x,y) coordinates of tube k are $Rsin a, Rcos a$, where $a = 2pifrac{k}{n}$



    The problem is: Given a centrifuge with N holes and K tubes, is it possible to balance it?



    example 1: given N = 6 possible values for K are 2,3,4,6.



    example 2: given N = 12, it is possible to balance 5 tubes: put 3 evenly dispersed (every 4th hole), then find a pair of opposite unoccupied holes and insert remaining 2 tubes there.



    example 3: given N = 10, it is impossible to balance 7 tubes: put 5 evenly dispersed, and there's no opposite unoccupied holes left!




    This is my code:



    import numpy as np

    N=int(input())
    angle = 2*np.pi/N
    z = complex(np.cos(angle), np.sin(angle))


    import itertools
    combs =
    lst = range(1,N)
    for i in range(2, N-1):
    combs.append(i)
    els = [list(x) for x in itertools.combinations(lst, i)]
    combs.append(els)


    count=1
    lis =
    while count<=len(combs):
    for a in range(len(combs[count])):
    s=0
    for b in range(len(combs[count][a])):
    s+=z**combs[count][a][b]
    if abs(s)<1e-10:
    lis.append(combs[count][a])
    count+=2


    lengths =
    for i in lis:
    if len(i) not in lengths:
    lengths.append(len(i))

    print(len(lengths)+1)


    The code works fine, but slows down after input size of above 20, and is practically unusable after the input grows to 50 or above, due to the for loops. How do I optimize it?










    share|improve this question









    New contributor




    Kristada673 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
    Check out our Code of Conduct.






















      up vote
      0
      down vote

      favorite









      up vote
      0
      down vote

      favorite











      So, the problem is, given an input N as the size of a centrifuge, I need to find out the number of balanced configurations. The full description is here.




      Centrifuge is a piece of equipment that puts multiple test tubes in rotation at very high speeds. It consists of a cylindrical rotor with holes situated evenly along the circumference of the rotor.
      Because the device is operating at high speeds, the center of mass of all tubes must coincide with the center of the rotor. We assume all tubes have the same mass.



      For the sake of simplicity, we also assume that tubes are point masses, fixed firmly to the rotor. All at the same distance from the center. You may safely assume the (x,y) coordinates of tube k are $Rsin a, Rcos a$, where $a = 2pifrac{k}{n}$



      The problem is: Given a centrifuge with N holes and K tubes, is it possible to balance it?



      example 1: given N = 6 possible values for K are 2,3,4,6.



      example 2: given N = 12, it is possible to balance 5 tubes: put 3 evenly dispersed (every 4th hole), then find a pair of opposite unoccupied holes and insert remaining 2 tubes there.



      example 3: given N = 10, it is impossible to balance 7 tubes: put 5 evenly dispersed, and there's no opposite unoccupied holes left!




      This is my code:



      import numpy as np

      N=int(input())
      angle = 2*np.pi/N
      z = complex(np.cos(angle), np.sin(angle))


      import itertools
      combs =
      lst = range(1,N)
      for i in range(2, N-1):
      combs.append(i)
      els = [list(x) for x in itertools.combinations(lst, i)]
      combs.append(els)


      count=1
      lis =
      while count<=len(combs):
      for a in range(len(combs[count])):
      s=0
      for b in range(len(combs[count][a])):
      s+=z**combs[count][a][b]
      if abs(s)<1e-10:
      lis.append(combs[count][a])
      count+=2


      lengths =
      for i in lis:
      if len(i) not in lengths:
      lengths.append(len(i))

      print(len(lengths)+1)


      The code works fine, but slows down after input size of above 20, and is practically unusable after the input grows to 50 or above, due to the for loops. How do I optimize it?










      share|improve this question









      New contributor




      Kristada673 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.











      So, the problem is, given an input N as the size of a centrifuge, I need to find out the number of balanced configurations. The full description is here.




      Centrifuge is a piece of equipment that puts multiple test tubes in rotation at very high speeds. It consists of a cylindrical rotor with holes situated evenly along the circumference of the rotor.
      Because the device is operating at high speeds, the center of mass of all tubes must coincide with the center of the rotor. We assume all tubes have the same mass.



      For the sake of simplicity, we also assume that tubes are point masses, fixed firmly to the rotor. All at the same distance from the center. You may safely assume the (x,y) coordinates of tube k are $Rsin a, Rcos a$, where $a = 2pifrac{k}{n}$



      The problem is: Given a centrifuge with N holes and K tubes, is it possible to balance it?



      example 1: given N = 6 possible values for K are 2,3,4,6.



      example 2: given N = 12, it is possible to balance 5 tubes: put 3 evenly dispersed (every 4th hole), then find a pair of opposite unoccupied holes and insert remaining 2 tubes there.



      example 3: given N = 10, it is impossible to balance 7 tubes: put 5 evenly dispersed, and there's no opposite unoccupied holes left!




      This is my code:



      import numpy as np

      N=int(input())
      angle = 2*np.pi/N
      z = complex(np.cos(angle), np.sin(angle))


      import itertools
      combs =
      lst = range(1,N)
      for i in range(2, N-1):
      combs.append(i)
      els = [list(x) for x in itertools.combinations(lst, i)]
      combs.append(els)


      count=1
      lis =
      while count<=len(combs):
      for a in range(len(combs[count])):
      s=0
      for b in range(len(combs[count][a])):
      s+=z**combs[count][a][b]
      if abs(s)<1e-10:
      lis.append(combs[count][a])
      count+=2


      lengths =
      for i in lis:
      if len(i) not in lengths:
      lengths.append(len(i))

      print(len(lengths)+1)


      The code works fine, but slows down after input size of above 20, and is practically unusable after the input grows to 50 or above, due to the for loops. How do I optimize it?







      python performance python-3.x programming-challenge






      share|improve this question









      New contributor




      Kristada673 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.











      share|improve this question









      New contributor




      Kristada673 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.









      share|improve this question




      share|improve this question








      edited 4 mins ago









      vnp

      38.4k13096




      38.4k13096






      New contributor




      Kristada673 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.









      asked 18 mins ago









      Kristada673

      1011




      1011




      New contributor




      Kristada673 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.





      New contributor





      Kristada673 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.






      Kristada673 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.



























          active

          oldest

          votes











          Your Answer





          StackExchange.ifUsing("editor", function () {
          return StackExchange.using("mathjaxEditing", function () {
          StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
          StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["\$", "\$"]]);
          });
          });
          }, "mathjax-editing");

          StackExchange.ifUsing("editor", function () {
          StackExchange.using("externalEditor", function () {
          StackExchange.using("snippets", function () {
          StackExchange.snippets.init();
          });
          });
          }, "code-snippets");

          StackExchange.ready(function() {
          var channelOptions = {
          tags: "".split(" "),
          id: "196"
          };
          initTagRenderer("".split(" "), "".split(" "), channelOptions);

          StackExchange.using("externalEditor", function() {
          // Have to fire editor after snippets, if snippets enabled
          if (StackExchange.settings.snippets.snippetsEnabled) {
          StackExchange.using("snippets", function() {
          createEditor();
          });
          }
          else {
          createEditor();
          }
          });

          function createEditor() {
          StackExchange.prepareEditor({
          heartbeatType: 'answer',
          autoActivateHeartbeat: false,
          convertImagesToLinks: false,
          noModals: true,
          showLowRepImageUploadWarning: true,
          reputationToPostImages: null,
          bindNavPrevention: true,
          postfix: "",
          imageUploader: {
          brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
          contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
          allowUrls: true
          },
          onDemand: true,
          discardSelector: ".discard-answer"
          ,immediatelyShowMarkdownHelp:true
          });


          }
          });






          Kristada673 is a new contributor. Be nice, and check out our Code of Conduct.










          draft saved

          draft discarded


















          StackExchange.ready(
          function () {
          StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fcodereview.stackexchange.com%2fquestions%2f210025%2fhow-do-i-optimize-my-python-code-for-balancing-a-centrifuge-with-a-given-input-s%23new-answer', 'question_page');
          }
          );

          Post as a guest















          Required, but never shown






























          active

          oldest

          votes













          active

          oldest

          votes









          active

          oldest

          votes






          active

          oldest

          votes








          Kristada673 is a new contributor. Be nice, and check out our Code of Conduct.










          draft saved

          draft discarded


















          Kristada673 is a new contributor. Be nice, and check out our Code of Conduct.













          Kristada673 is a new contributor. Be nice, and check out our Code of Conduct.












          Kristada673 is a new contributor. Be nice, and check out our Code of Conduct.
















          Thanks for contributing an answer to Code Review Stack Exchange!


          • Please be sure to answer the question. Provide details and share your research!

          But avoid



          • Asking for help, clarification, or responding to other answers.

          • Making statements based on opinion; back them up with references or personal experience.


          Use MathJax to format equations. MathJax reference.


          To learn more, see our tips on writing great answers.





          Some of your past answers have not been well-received, and you're in danger of being blocked from answering.


          Please pay close attention to the following guidance:


          • Please be sure to answer the question. Provide details and share your research!

          But avoid



          • Asking for help, clarification, or responding to other answers.

          • Making statements based on opinion; back them up with references or personal experience.


          To learn more, see our tips on writing great answers.




          draft saved


          draft discarded














          StackExchange.ready(
          function () {
          StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fcodereview.stackexchange.com%2fquestions%2f210025%2fhow-do-i-optimize-my-python-code-for-balancing-a-centrifuge-with-a-given-input-s%23new-answer', 'question_page');
          }
          );

          Post as a guest















          Required, but never shown





















































          Required, but never shown














          Required, but never shown












          Required, but never shown







          Required, but never shown

































          Required, but never shown














          Required, but never shown












          Required, but never shown







          Required, but never shown







          Popular posts from this blog

          Ellipse (mathématiques)

          Quarter-circle Tiles

          Mont Emei