time   calls  line
                  1 function p = nextpow2(n)
                  2 %NEXTPOW2 Next higher power of 2.
                  3 %   NEXTPOW2(N) returns the first P such that 2.^P >= abs(N).  It is
                  4 %   often useful for finding the nearest power of two sequence
                  5 %   length for FFT operations.
                  6 %
                  7 %   Class support for input N:
                  8 %      float: double, single
                  9 %
                 10 %   See also LOG2, POW2.
                 11 
                 12 %   Copyright 1984-2009 The MathWorks, Inc. 
                 13 %   $Revision: 5.11.4.4 $  $Date: 2009/07/06 20:37:15 $
                 14 
           138   15 [f,p] = log2(abs(n)); 
                 16 
                 17 % Check for exact powers of 2.
           138   18 k = (f == 0.5); 
           138   19 p(k) = p(k)-1; 
                 20 
                 21 % Check for infinities and NaNs
           138   22 k = ~isfinite(f); 
           138   23 p(k) = f(k);