parameters: (self, rank)
docstring: Reduce the rank of the matrix by dropping oldest vectors.
docstring_summary: Reduce the rank of the matrix by dropping oldest vectors.
docstring_tokens: Reduce the rank of the matrix by dropping oldest vectors .
function: def simple_reduce(self, rank):
          """
          Reduce the rank of the matrix by dropping oldest vectors.
          """
          if self.collapsed is not None:
              return
          assert rank > 0
          while len(self.cs) > rank:
              del self.cs[0]
              del self.ds[0]
function_tokens: def simple_reduce ( self , rank ) : if self . collapsed is not None : return assert rank > 0 while len ( self . cs ) > rank : del self . cs [ 0 ] del self . ds [ 0 ]