Alice Invernizzi wrote: > Therefore, is not clear to me why in numpy the size of an array can be > changed (either with the 'returning-value' resize() function either with > the 'in-place' array method resize()).
> Would you please be so kind to give some explanation for the existence > of resize operator for numpy array? I don't find I use it that much, but it can be useful for the same reason that it is for lists, etc. > If array size can be change, > what are the real advantages of using numpy array instead of list object? This I can really answer! the "it's a known size" property of an nd-array is probably the least useful one I can think of. I think the pre-known size aspect of array objects is really an artifact of wanting efficient storage and processing, rather than a feature -- particularly in a dynamic language. As for other advantages: arrays are homogeneous data -- giving far more efficiency in a dynamic language arrays are n-d -- you can slice and dice them as such -- it's easy to extract either a row or a column from a 2-d array, for instance. slices of arrays are arrays with a view on the same data: this makes it easy to manipulate portions of an array with the same code you'd manipulate a full array. array broadcasting easy and efficient interchange of raw data with other data types, from C, C++ , Fortran, etc code. and I could go on! You might actually ask the question the other way -- if you can re-size an array -- why do you ever need to use a list? -Chris -- Christopher Barker, Ph.D. Oceanographer Emergency Response Division NOAA/NOS/OR&R (206) 526-6959 voice 7600 Sand Point Way NE (206) 526-6329 fax Seattle, WA 98115 (206) 526-6317 main reception chris.bar...@noaa.gov _______________________________________________ NumPy-Discussion mailing list NumPy-Discussion@scipy.org http://mail.scipy.org/mailman/listinfo/numpy-discussion
