Source Code for Module geometry.basic_utils

 1  from . import GeometryConstants, contract, np, new_contract 
 2  import warnings 
 3   
 4  new_contract('R1', 'array[1]') 
 5  new_contract('R2', 'array[2]') 
 6  new_contract('R3', 'array[3]') 
 7   
 8   
 9  @new_contract 
10  @contract(x='array') 
11 -def finite(x): 
12      # TODO: make into standard thing 
13      return np.isfinite(x).all() 
14   
15   
16  @contract(s='array') 
17 -def normalize_length(s, norm=2): 
18      ''' Normalize an array such that it has unit length in the given norm. ''' 
19      sn = np.linalg.norm(s, norm) 
20      if np.allclose(sn, 0, atol=GeometryConstants.atol_zero_norm): 
21          raise ValueError('Norm is zero') 
22      else: 
23          return s / sn 
24   
25   
26  @contract(s='array') 
27 -def normalize_length_or_zero(s, norm=2): 
28      '''  
29          Normalize an array such that it has unit length in the given norm;  
30          if the norm is close to zero, the zero vector is returned.      
31      ''' 
32      sn = np.linalg.norm(s, norm) 
33      if np.allclose(sn, 0, atol=GeometryConstants.atol_zero_norm): 
34          return s 
35      else: 
36          return s / sn 
37   
38   
39 -def deprecated(func): 
40      """This is a decorator which can be used to mark functions 
41      as deprecated. It will result in a warning being emitted 
42      when the function is used.""" 
43      def new_func(*args, **kwargs): 
44          warnings.warn("Call to deprecated function %s." % func.__name__, 
45                        category=DeprecationWarning, stacklevel=2) 
46          return func(*args, **kwargs) 
47      new_func.__name__ = func.__name__ 
48      new_func.__doc__ = func.__doc__ 
49      new_func.__dict__.update(func.__dict__) 
50      return new_func 
51   
52   
53 -def safe_arccos(x): 
54      '''  
55          Returns the arcosine of x, clipped between -1 and 1. 
56           
57          Use this when you know x is a cosine, but it might be 
58          slightly over 1 or below -1 due to numerical errors. 
59      ''' 
60      return np.arccos(np.clip(x, -1.0, 1.0)) 
61