Re: [Numpy-discussion] Masking an array with another array

2009-08-12 Thread John [H2O]
I suspect I am trying to do something similar... I would like to create a mask where I have data. In essence, I need to return True where x,y is equal to lon,lat I suppose a setmember solution may somehow be more elegant, but this is what I've worked up for now... suggestions? def

Re: [Numpy-discussion] Masking an array with another array

2009-04-23 Thread josef . pktd
On Thu, Apr 23, 2009 at 1:24 AM, Gökhan SEVER gokhanse...@gmail.com wrote: Ahaa,, Thanks Gaël. That method is more elegance than the previous inputs, and the simplest of all. Although one line of import this says: There should be one-- and preferably only one --obvious way to do it. I

Re: [Numpy-discussion] Masking an array with another array

2009-04-23 Thread Neil Crighton
josef.pktd at gmail.com writes: setmember1d is very fast compared to the other solutions for large b. However, setmember1d requires that both arrays only have unique elements. So it doesn't work if, for example, your first array is a data vector with member ship in different groups

[Numpy-discussion] Masking an array with another array

2009-04-22 Thread Gökhan SEVER
Hello, Could you please give me some hints about how to mask an array using another arrays like in the following example. In [14]: a = arange(5) In [15]: a Out[15]: array([0, 1, 2, 3, 4]) and my secondary array is b In [16]: b = array([2,3]) What I want to do is to mask a with b values and

Re: [Numpy-discussion] Masking an array with another array

2009-04-22 Thread Pierre GM
On Apr 22, 2009, at 5:21 PM, Gökhan SEVER wrote: Hello, Could you please give me some hints about how to mask an array using another arrays like in the following example. What about that ? numpy.logical_or.reduce([a==i for i in b]) ___

Re: [Numpy-discussion] Masking an array with another array

2009-04-22 Thread Gökhan SEVER
Yes Pierre, I like this one line of elegances in Python a lot. I was thinking that the answer lies in somewhere in masked array operations, but I proved wrong. Thanks for your input on this small riddle. Here is another way of doing that. (That's what I thought of initially and what Matthias

Re: [Numpy-discussion] Masking an array with another array

2009-04-22 Thread josef . pktd
On Wed, Apr 22, 2009 at 8:18 PM, Gökhan SEVER gokhanse...@gmail.com wrote: Yes Pierre, I like this one line of elegances in Python a lot. I was thinking that the answer lies in somewhere in masked array operations, but I proved wrong. Thanks for your input on this small riddle. Here is

Re: [Numpy-discussion] Masking an array with another array

2009-04-22 Thread Pierre GM
On Apr 22, 2009, at 9:03 PM, josef.p...@gmail.com wrote: I prefer broad casting to list comprehension in numpy: Pretty neat! I still dont have the broadcasting reflex. Now, any idea which one is more efficient in terms of speed? in terms of temporaries?

Re: [Numpy-discussion] Masking an array with another array

2009-04-22 Thread josef . pktd
On Wed, Apr 22, 2009 at 10:45 PM, Pierre GM pgmdevl...@gmail.com wrote: On Apr 22, 2009, at 9:03 PM, josef.p...@gmail.com wrote: I prefer broad casting to list comprehension in numpy: Pretty neat! I still dont have the broadcasting reflex. Now, any idea which one is more efficient in terms

Re: [Numpy-discussion] Masking an array with another array

2009-04-22 Thread Gael Varoquaux
On Wed, Apr 22, 2009 at 04:21:05PM -0500, Gökhan SEVER wrote: Could you please give me some hints about how to mask an array using another arrays like in the following example. In [14]: a = arange(5) In [15]: a Out[15]: array([0, 1, 2, 3, 4]) and my secondary array is b

Re: [Numpy-discussion] Masking an array with another array

2009-04-22 Thread Gökhan SEVER
Ahaa,, Thanks Gaël. That method is more elegance than the previous inputs, and the simplest of all. Although one line of import this says: There should be one-- and preferably only one --obvious way to do it. I always find many different ways of implementing ideas in Python world. Gökhan On