First consider this example of column_stack import numpy as np x = np.random.random((5,1)) y = np.random.random((5,3))
arr = np.column_stack((x[[]], y)) # this fails which is expected arr = np.column_stack((x[:,[]], y)) # this happily works I guess because x[:,[]] # array([], shape=(5, 0), dtype=float64) Now if I want to something analogous with structured array I don't see off the bat how. Is this desired behavior? At the very least it's a partial bug I think. import numpy.lib.recfunctions as nprf xx = np.zeros(5, dtype=[('variable',float)]) xx['variable'] = np.random.random(5) yy = np.random.random((5,2)) arr2 = nprf.append_fields((xx[[]][:], ['var1','var2'], yy.T, usemask=False) arr2 array([(1e+20, 0.24277386045950911, 0.3801949115638894), (1e+20, 0.81574702386474807, 0.95094000248766541), (1e+20, 0.7901945469951196, 0.49315509384277167), (1e+20, 0.84140435880491093, 0.37125966704723368), (1e+20, 0.66595836283749366, 0.18154580574750145)], dtype=[('variable', '<f8'), ('var1', '<f8'), ('var2', '<f8')]) I think it should either fail or return yy. Surely, it shouldn't fill in with 1e20 (ignoring fill_value). I don't think it should do any padding if usemask=False. Am I missing something? Bug report/enhancement ticket? Skipper _______________________________________________ NumPy-Discussion mailing list NumPy-Discussion@scipy.org http://mail.scipy.org/mailman/listinfo/numpy-discussion