Dear all, I am new to numarray and as I am trying to use it day-by-day I am now wondering about certain numeric/numarray design issues. Please forgive me / correct me as I probably misunderstood certain issues. -- Why did you choose row-major instead of column major format as practiced by R/octave/matlab... Doesn't that mean performance problems as fortran/blas is optimized if you work with the transposed version ? -- why do vectors have no 'orientation', i.e. there are only row but no column vectors (or why do you treat matrices/vectors differently, i.e. have vectors at all as a separate type) numarray: a=array([[1,2,3],[4,5,6],[7,8,9]])

a[0,:] array([1, 2, 3]) a[:,0] array([1, 4, 7])

vs. octave: a=[1,2,3;4,5,6;7,8,9];

a(1,:) ans = 1 2 3 a(:,1) ans = 1 4 7

-- How can one obtain submatrices from full matrices: numarray gives only elements (which is very, very rarely needed and should IMHO rather be some extra function):

i=[0,1] j=[0,2] a[i,j] array([1, 6])

vs octave:

i=[1,2]; j=[1,3]; a(i,j) ans = 1 3 4 6

all one can do in numarray currently is as awkward as this:

a.take(i,0).take(j,1) array([[1, 3], [4, 6]])

also mixing slice and variable does not work a[:,i] - hmmhh seems that is a major issue for me... -- why don't you allow iterating over the whole matrix via a single index ? i.e. a[3] Traceback (most recent call last): File "<stdin>", line 1, in ? IndexError: Index out of range vs octave

a(4) ans = 2

Are there more elegant ways to do this ? Which issues are likely to be fixed in the future ? Best regards, Soeren