Gaz said:
Hi guys. I've been lookig for this in the numpy pdf manual, in this
group and on google, but i could not get an answer...
You will probably want to look or ask on the numpy list, too.
https://lists.sourceforge.net/lists/listinfo/numpy-discussion
Is there a way to create a custom data type (eg: Name: string(30), Age:
int(2), married: boolean, etc) and then use that custom data in a
matrix? Actually, this is a two question question
Yes. Use record arrays. They are discussed in section 8.5 of the _The Guide to
NumPy_ if you have the book. There is another example of using record arrays on
the SciPy wiki (although it is less focused on combining different data types
than it is named column access):
http://www.scipy.org/RecordArrays
Here is an example:
In [18]: from numpy import *
In [19]: rec.fromrecords([['Robert', 25, False], ['Thomas', 53, True]],
names='name,age,married', formats=['S30', int, bool])
Out[19]:
recarray([('Robert', 25, False), ('Thomas', 53, True)],
dtype=[('name', '|S30'), ('age', '>i4'), ('married', '|b1')])
In [21]: Out[19].name
Out[21]:
chararray([Robert, Thomas],
dtype='|S30')
In [22]: Out[19].age
Out[22]: array([25, 53])
In [23]: Out[19].married
Out[23]: array([False, True], dtype=bool)
You can also use object arrays if you need to implement classes and not just
dumb, basic types:
In [33]: class Hex(dict):
....: def __init__(self, **kwds):
....: dict.__init__(self, **kwds)
....: self.__dict__ = self
....:
....:
In [34]: field = array([Hex(color=(0,0,0), owner='Player1', x=10, y=20,
etc='Black hex owned by Player1'),
....: Hex(color=(1,1,1), owner='Player2', x=10, y=21,
etc='White hex owned by Player2')], dtype=object)
In [35]:
In [35]: field
Out[35]: array([{'y': 20, 'etc': 'Black hex owned by Player1', 'color': (0, 0,
0), 'owner': 'Player1', 'x': 10}, {'y': 21, 'etc': 'White hex owned by Player2',
'color': (1, 1, 1), 'owner': 'Player2', 'x': 10}], dtype=object)
--
Robert Kern
(e-mail address removed)
"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