On Fri, May 13, 2011 at 4:38 PM, Robert Kern <robert.kern@gmail.com> wrote:
On Fri, May 13, 2011 at 09:58, Bruce Southey <bsouthey@gmail.com> wrote:
Hi, How do you create a 'single' structured array using np.array()? Basically I am attempting to do something like this that does not work: a=np.array([1,2, 3,4, 5,6], dtype=np.dtype([('foo', int)]))
I realize that this is essentially redundant as if A is an 1-d array then a structured array with a named field 'foo' is the same thing - A would be A['foo'], just shorter.
So if that is valid then a clearer error message is required to indicate this and provide the suitable error message to address ticket 1264 (http://projects.scipy.org/numpy/ticket/1264).
$ python Python 2.7 (r27:82500, Sep 16 2010, 18:02:00) [GCC 4.5.1 20100907 (Red Hat 4.5.1-3)] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> import numpy as np >>> a=np.array([1,2, 3,4, 5,6], dtype=np.dtype([('foo', int)])) Traceback (most recent call last): File "<stdin>", line 1, in <module> TypeError: expected a readable buffer object >>> np.array([(1,2), (3,4), (5,6)], dtype=np.dtype([('foo', int), ('foo2', int)])) array([(1, 2), (3, 4), (5, 6)], dtype=[('foo', '<i8'), ('foo2', '<i8')]) >>> a=np.array([(1), (3), (5)], dtype=np.dtype([('foo', int)])) Traceback (most recent call last): File "<stdin>", line 1, in <module> TypeError: expected a readable buffer object
You are missing the commas:
[~] |12> a=np.array([(1,), (3,), (5,)], dtype=np.dtype([('foo', int)]))
[~] |13> a array([(1,), (3,), (5,)], dtype=[('foo', '<i4')])
-- Robert Kern
"I have come to believe that the whole world is an enigma, a harmless enigma that is made terrible by our own mad attempt to interpret it as though it had an underlying truth." -- Umberto Eco _______________________________________________ NumPy-Discussion mailing list NumPy-Discussion@scipy.org http://mail.scipy.org/mailman/listinfo/numpy-discussion
I am still 'digesting' this and what it means. In any case, many thanks! Bruce