On Mon, Feb 25, 2013 at 9:20 PM, Sebastian Berg <sebast...@sipsolutions.net> wrote: > On Mon, 2013-02-25 at 10:50 -0500, Skipper Seabold wrote: >> On Mon, Feb 25, 2013 at 10:43 AM, Till Stensitzki <mail.t...@gmx.de> >> wrote: >> > >> > First, sorry that i didnt search for an old thread, but because i >> disagree with >> > conclusion i would at least address my reason: >> > >> >> I don't like >> >> np.abs(arr).max() >> >> because I have to concentrate to much on the braces, especially if >> arr >> >> is a calculation >> > >> > This exactly, adding an abs into an old expression is always a >> little annoyance >> > due to the parenthesis. The argument that np.abs() also works is >> true for >> > (almost?) every other method. The fact that so many methods already >> exists, >> > especially for most of the commonly used functions (min, max, dot, >> mean, std, >> > argmin, argmax, conj, T) makes me missing abs. Of course, if one >> would redesign >> > the api, one would drop most methods (i am looking at you ptp and >> byteswap). But >> > the objected is already cluttered and adding abs is imo logical >> application of >> > "practicality beats purity". >> > >> >> I tend to agree here. The situation isn't all that dire for the number >> of methods in an array. No scrolling at reasonably small terminal >> sizes. >> >> [~/] >> [3]: x. >> x.T x.copy x.getfield x.put x.std >> x.all x.ctypes x.imag x.ravel >> x.strides >> x.any x.cumprod x.item x.real x.sum >> x.argmax x.cumsum x.itemset x.repeat >> x.swapaxes >> x.argmin x.data x.itemsize x.reshape x.take >> x.argsort x.diagonal x.max x.resize >> x.tofile >> x.astype x.dot x.mean x.round >> x.tolist >> x.base x.dtype x.min x.searchsorted >> x.tostring >> x.byteswap x.dump x.nbytes x.setfield >> x.trace >> x.choose x.dumps x.ndim x.setflags >> x.transpose >> x.clip x.fill x.newbyteorder x.shape x.var >> x.compress x.flags x.nonzero x.size x.view >> x.conj x.flat x.prod x.sort >> x.conjugate x.flatten x.ptp x.squeeze >> >> > Two small things (not sure if it matters much). But first almost all of > these methods are related to the container and not the elements. Second > actually using a method arr.abs() has a tiny pitfall, since abs would > work on numpy types, but not on python types. This means that: > > np.array([1, 2, 3]).max().abs() > > works, but > > np.array([1, 2, 3], dtype=object).max().abs() > > breaks. Python has a safe name for abs already...
>>> (np.array([1, 2, 3], dtype=object)).max() 3 >>> (np.array([1, 2, 3], dtype=object)).__abs__().max() 3 >>> (np.array([1, 2, '3'], dtype=object)).__abs__() Traceback (most recent call last): File "<stdin>", line 1, in <module> TypeError: bad operand type for abs(): 'str' >>> map(abs, [1, 2, 3]) [1, 2, 3] >>> map(abs, [1, 2, '3']) Traceback (most recent call last): File "<stdin>", line 1, in <module> TypeError: bad operand type for abs(): 'str' I don't see a difference. (I don't expect to use max abs on anything else than numbers.) Josef > > >> I find myself typing things like >> >> arr.abs() >> >> and >> >> arr.unique() >> >> quite often. >> >> Skipper >> _______________________________________________ >> NumPy-Discussion mailing list >> NumPy-Discussion@scipy.org >> http://mail.scipy.org/mailman/listinfo/numpy-discussion > > > _______________________________________________ > NumPy-Discussion mailing list > NumPy-Discussion@scipy.org > http://mail.scipy.org/mailman/listinfo/numpy-discussion _______________________________________________ NumPy-Discussion mailing list NumPy-Discussion@scipy.org http://mail.scipy.org/mailman/listinfo/numpy-discussion
