52 lines
1.1 KiB
Python
52 lines
1.1 KiB
Python
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import sys
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import math
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def x( point ):
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return point[0]
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def y( point ):
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return point[1]
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def LOG( *args ):
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"""Print something on stderr and flush"""
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for msg in args:
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sys.stderr.write( str(msg) )
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sys.stderr.write(" ")
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sys.stderr.flush()
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def LOGN( *args ):
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"""Print something on stdeer, with a trailing new line, and flush"""
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LOG( *args )
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LOG("\n")
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def adjacency_from_set( segments ):
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graph = {}
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for start,end in segments:
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graph[start] = graph.get( start, [] )
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graph[start].append( end )
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graph[end] = graph.get( end, [] )
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graph[end].append( start )
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return graph
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def vertices_from_set( segments ):
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vertices = set()
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for start,end in segments:
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vertices.add(start)
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vertices.add(end)
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return vertices
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def tour(lst):
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# consecutive pairs in lst + last-to-first element
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for a,b in zip(lst, lst[1:] + [lst[0]]):
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yield (a,b)
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def euclidian_distance( ci, cj, graph = None):
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return math.sqrt( float(ci[0] - cj[0])**2 + float(ci[1] - cj[1])**2 )
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