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A small script for graphing 2d standing waves nodes and anti-nodes

https://www.desmos.com/calculator/a7puiruynb for playing around with mode 0 more easily

# libs
from kandinsky import *
from math import *

# constants
WIDTH,HEIGHT = 320,240
scalex,scaley = 100,100
precision = 1

# default preset
mode = 0
n    = 3
m    = 4
k    = 0.01
g    = 100

# preset loading
preset = input('preset: ')
if preset != '':
  v = ''
  i = 0
  for c in preset:
    if preset[0] == ',':
      if c == ',':
        if v:
          v = float(v)
          if i==1: mode=int(v)
          if i==2: n=v
          if i==3: m=v
          if i==4: k=v
          if i==5: g=v
        v = ''
        i += 1
      else:
        v += c
    else:
      if c in 'Mnmkg':
        v = float(v)
        if c=='M':mode=int(v)
        if c=='n':n=v
        if c=='m':m=v
        if c=='k':k=v
        if c=='g':g=v
        v = ''
      else:
        v += c

preset = bool(len(preset))

if not preset:
  print('''
modes
 0: anti-node graph
 1: node magnitude graph
 2: both
  ''')
  
  mode = input('mode: ') or mode
  
mode = str(mode)

if mode == '0':
  if not preset:
    # values descriptions
    print(''' n: n parameter
 m: m parameter
 k: threshold''')
    
    # settings
    n = float(input('n: ') or n)
    m = float(input('m: ') or m)
    k = float(input('k: ') or k)
  
  # fn
  def fn(x,y):
    return abs(sin(n*pi*x)*sin(m*pi*y) - sin(m*pi*x)*sin(n*pi*y)) < k
    
  # grpahing
  rx = -WIDTH/2
  while rx < WIDTH/2:
    ry = -HEIGHT/2
    while ry < HEIGHT/2:
      x,y = rx/scalex,ry/scaley*-1    
      if fn(x,y):
        set_pixel(round(WIDTH/2+rx),round(HEIGHT/2+ry),(255,0,0))
      ry += precision
    rx += precision
elif mode == '1':
  if not preset:
    # values descriptions
    print(''' n: n parameter
 m: m parameter
 g: gain''')
  
    # settings
    n = float(input('n: ') or n)
    m = float(input('m: ') or m)
    g = float(input('g: ') or g)
    
  gain = g
    
  # fn
  def fn(x,y):
    return sin(n*pi*x)*sin(m*pi*y) - sin(m*pi*x)*sin(n*pi*y) *gain
    
  # graphing
  rx = -WIDTH/2
  while rx < WIDTH/2:
    ry = -HEIGHT/2
    while ry < HEIGHT/2:
      x,y = rx/scalex,ry/scaley*-1    
      r = 128-fn(x,y)*2
      b = 128+fn(x,y)*2
      set_pixel(round(WIDTH/2+rx),round(HEIGHT/2+ry),(r,0,b))
      ry += precision
    rx += precision
elif mode == "2":
  if not preset:
    # values descriptions
    print(''' n: n parameter
 m: m parameter
 k: threshold
 g: gain''')
  
    # settings
    n = float(input('n: ') or n)
    m = float(input('m: ') or m)
    k = float(input('k: ') or k)
    g = float(input('g: ') or g)
    
  gain = g
  
  # fn
  def fn(x,y):
    return sin(n*pi*x)*sin(m*pi*y) - sin(m*pi*x)*sin(n*pi*y) *gain
  def fn2(x,y):
    return abs(sin(n*pi*x)*sin(m*pi*y) - sin(m*pi*x)*sin(n*pi*y))<k
    
  # graphing
  rx = -WIDTH/2
  while rx < WIDTH/2:
    ry = -HEIGHT/2
    while ry < HEIGHT/2:
      x,y = rx/scalex,ry/scaley*-1    
      if fn2(x,y):
        set_pixel(round(WIDTH/2+rx),round(HEIGHT/2+ry),((abs(fn(x,y))-k)/k**4,255,(abs(fn(x,y))-k)/k**4))
      else:
        r = 128-fn(x,y)*2
        b = 128+fn(x,y)*2
        set_pixel(round(WIDTH/2+rx),round(HEIGHT/2+ry),(r,0,b))
      ry += precision
    rx += precision
else:
  print('Invalid mode \'{}\''.format(mode))