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Pickle incompatibility of numpy arrays between Python 2 and 3
I am trying to load the MNIST dataset linked here in Python 3.2 using this program:
7 Answers
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Waiting until two async blocks are executed before starting another block
...
305
Use dispatch groups: see here for an example, "Waiting on Groups of Queued Tasks" in the "Disp...
How to calculate moving average using NumPy?
...
173
If you just want a straightforward non-weighted moving average, you can easily implement it with...
Removing duplicates in lists
...ample should cover whatever you are trying to do:
>>> t = [1, 2, 3, 1, 2, 5, 6, 7, 8]
>>> t
[1, 2, 3, 1, 2, 5, 6, 7, 8]
>>> list(set(t))
[1, 2, 3, 5, 6, 7, 8]
>>> s = [1, 2, 3]
>>> list(set(t) - set(s))
[8, 5, 6, 7]
As you can see from the example resu...
How to convert a scala.List to a java.util.List?
...ort scala.collection.jcl.ArrayList
unconvertList(new ArrayList ++ List(1,2,3))
From Scala 2.8 onwards:
import scala.collection.JavaConversions._
import scala.collection.mutable.ListBuffer
asList(ListBuffer(List(1,2,3): _*))
val x: java.util.List[Int] = ListBuffer(List(1,2,3): _*)
However, asLis...
How to swap keys and values in a hash
... (in essence, by letting you access keys through values):
{a: 1, b: 2, c: 3}.key(1)
=> :a
If you want to keep the inverted hash, then Hash#invert should work for most situations:
{a: 1, b: 2, c: 3}.invert
=> {1=>:a, 2=>:b, 3=>:c}
BUT...
If you have duplicate values, invert will...
No secret option provided to Rack::Session::Cookie warning?
I am running Rails 3.2.3, Ruby 1.9 under Fedora 17. I get this warning, when I run rails s , and how do I fix?
7 Answers
...
[] and {} vs list() and dict(), which is better?
...gt;> from timeit import timeit
>>> timeit("[]")
0.040084982867934334
>>> timeit("list()")
0.17704233359267718
>>> timeit("{}")
0.033620194745424214
>>> timeit("dict()")
0.1821558326547077
and for non-empty:
>>> timeit("[1,2,3]")
0.24316302770330367
...
Syntax for creating a two-dimensional array
...ti[0] = new int[10];
multi[1] = new int[10];
multi[2] = new int[10];
multi[3] = new int[10];
multi[4] = new int[10];
Note that every element will be initialized to the default value for int, 0, so the above are also equivalent to:
int[][] multi = new int[][]{
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
...