matrix.py

   1 import urlparse
   2
   3 import scipy
   4 import scipy.linalg
   5 from scipy import *
   6
   7 def null(A, eps=1e-15):
   8     u, s, vh = scipy.linalg.svd(A)
   9     null_mask = (s <= eps)
  10     null_space = scipy.compress(null_mask, vh, axis=0)
  11     return scipy.transpose(null_space)
  12
  13 def eigenvalues(A, eps=1e-15):
  14     u, s, vh = scipy.linalg.svd(A)
  15     return s
  16
  17 def application(environ, start_response):
  18     if environ['REQUEST_METHOD'] == 'POST':
  19         post_data = environ['wsgi.input'].read()
  20
  21         output = "<pre>"
  22         #output += post_data
  23         output += "<br>"
  24
  25         post_data = urlparse.parse_qsl(post_data, True, True)
  26
  27         data_string = str(post_data[0][1])
  28         data_rows = data_string.splitlines()
  29         for index, row in enumerate(data_rows):
  30             data_rows[index] = row.split()
  31
  32         given_matrix = data_rows
  33         null_space = null(given_matrix)
  34         try:
  35             null_space = null_space / null_space.max()
  36         except:
  37             pass
  38
  39 #        la, v = scipy.linalg.eig(given_matrix)
  40 #       output += "eigenvalues:<br>"
  41 #        for l in la:
  42 #            output += str(l)
  43         determinant = scipy.linalg.det(given_matrix)
  44
  45         output += "<h1>"
  46         output += "nullspace:<br>"
  47         output += str(null_space)
  48         output += "<br><br>"
  49         output += "eigenvalues:<br>"
  50         output += str(eigenvalues(given_matrix))
  51         output += "<br><br>"
  52         output += "determinant:<br>"
  53         output += str(determinant)
  54 #       output += "<br><br>"
  55 #       output += "eigenvalues:<br>"
  56 #       output += str(l1)
  57 #       output += "<br><br>"
  58 #       output += "eigenvectors:<br>"
  59 #       output +=  str(v[:,0][0])
  60         output += "</h1>"
  61
  62     # send results
  63     output_len = sum(len(line) for line in output)
  64     start_response('200 OK', [('Content-type', 'text/html'),
  65                               ('Content-Length', str(output_len))])
  66     return output