Hi, I don't really understand how integrate.romb is supposed to work. First of all its docstring is not really clear: """ Uses Romberg integration to integrate y(x) using N samples along the given axis which are assumed equally spaced with distance dx. The number of samples must be 1 + a non-negative power of two: N=2**k + 1 """ Reading this it is not clear that y is supposed to be a vector, and not a function. Second if I run it on a really simple test case, I get an error, and it seems the error is due to a trivial bug in the code: In [13]: x = arange(0,2**10+1) In [14]: integrate.romb(x) --------------------------------------------------------------------------- exceptions.TypeError Traceback (most recent call last) /home/varoquau/<ipython console> /usr/lib/python2.4/site-packages/scipy/integrate/quadrature.py in romb(y, dx, axis, show) 256 for i in range(2,k+1): 257 start >>= 1 --> 258 slice_R = tupleset(slice_R, slice(start,stop,step)) 259 step >>= 1 260 R[(i,1)] = 0.5*(R[(i-1,1)] + h*add.reduce(y[slice_R],axis)) TypeError: tupleset() takes exactly 3 arguments (2 given) In [15]: And indeed if you check out the code for tupleset, you find this : def tupleset(t, i, value): l = list(t) l[i] = value return tuple(l) It looks to me there has been some refactoring and the integrate.romb has been left out. Cheers, Gaël