On Tue, Oct 6, 2009 at 4:28 PM, Pierre GM
On Oct 6, 2009, at 4:42 PM, Gökhan Sever wrote:
Hello,
I have a sample masked array data as shown below.
1-) When I list the whole array I see the fill value correctly. However below that line, when I do access the 5th element, fill_value flies upto 1e+20. What might be wrong here?
Nothing. Your 5th element is the special constant numpy.ma.masked, which has its own filling_value by default. I'll check whether it's worth inheriting the fill_value from the original array. If you could give me a test case where you'd need that value to keep the original filling_value, that'd help me make up my mind.
Seeing a different filling value is causing confusion. Both for myself, and when I try to demonstrate the usage of masked array to other people. Also say, if I want to replace that one element back to its original state will it use fill_value as 1e+20 or 999999.9999?
2-) What is wrong with the arccos calculation? Should not that result the same as with cos(d) result?
I first tested on 1.3.0, and later on my laptop using 1.4dev version which is about an old month built. Once again the results for each arc... function I[31]: d O[31]: masked_array(data = --, mask = True, fill_value = 1e+20) I[26]: arccos(d) O[26]: masked_array(data = 1.57079632679, mask = False, fill_value = 1e+20) I[28]: arccosh(d) O[28]: masked_array(data = nan, mask = False, fill_value = 1e+20) I[30]: arcsin(d) O[30]: masked_array(data = 0.0, mask = False, fill_value = 1e+20) I[32]: arcsinh(d) O[32]: masked_array(data = --, mask = True, fill_value = 1e+20) I[33]: arctan(d) O[33]: masked_array(data = --, mask = True, fill_value = 1e+20) I[35]: arctanh(d) O[35]: masked_array(data = 0.0, mask = False, fill_value = 1e+20) Only arcsinh and arctan results correctly.
Mmh, what numpy are you using ? When I try with a recent one, np.arccos does output ma.masked... _______________________________________________ NumPy-Discussion mailing list NumPy-Discussion@scipy.org http://mail.scipy.org/mailman/listinfo/numpy-discussion
-- Gökhan