ウラムの螺旋

Spiral.py

#!/usr/bin/python
# -*- coding utf8 -*-



def isPrime(n):
  if n == 1:
    return False
  elif n == 2:
    return True
  else:
    for i in range(2, n):
      d, m = divmod(n, i)
      if m == 0:
        return False
    return True


class Matrix(object):
  def __init__(self, size, filter=None):
    self.size = size
    self.matrix = {}
    self._filter = filter

  def filter(self, n):
    if self._filter:
      return self._filter(n)
    return n

  def make(self, n=None, origin=None):
    if n is None:
      n = self.size
    if origin is None:
      origin = (0, 0)
    print n, origin
    assert n > 0
    if n==1:
      self.matrix[origin] = 1
      return

    d, isodd = divmod(n, 2)
    if isodd:
      for i in range(n):
        self.matrix[(origin[0], origin[1]+i)] = self.filter(n*n - i)
      for i in range(n-1):
        self.matrix[(origin[0]+1+i, origin[1]+n-1)] = self.filter(n*n - n - i)
      o2 = origin[0]+1, origin[1]
    else:
      for i in range(n):
        self.matrix[(origin[0]+n-1, origin[1]+n-1-i)] = self.filter(n*n - i)
      for i in range(n-1):
        self.matrix[(origin[0]+n-2-i, origin[1])] = self.filter(n*n - n - i)
      o2 = origin[0],  origin[1] + 1
    self.make(n-1, o2)

  def print_matrix(self):
    for j in range(self.size):
      line = []
      for i in range(self.size):
        line.append('%3i'%(self.matrix[(i, j)],))
      print '|'.join(line)


m = Matrix(6)
m.make()
m.print_matrix()

print isPrime(7)
print isPrime(17)
print isPrime(29)
print isPrime(169)

m = Matrix(11, isPrime)
m.make()
m.print_matrix()