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How to find out which package version is loaded in R?
...plish that.
> sessionInfo()
R version 2.15.0 (2012-03-30)
Platform: x86_64-pc-linux-gnu (64-bit)
locale:
[1] LC_CTYPE=en_US.UTF-8 LC_NUMERIC=C LC_TIME=en_US.UTF-8 LC_COLLATE=en_US.UTF-8
[5] LC_MONETARY=en_US.UTF-8 LC_MESSAGES=en_US.UTF-8 LC_PAPER=C ...
Why return NotImplemented instead of raising NotImplementedError
...
It's because __lt__() and related comparison methods are quite commonly used indirectly in list sorts and such. Sometimes the algorithm will choose to try another way or pick a default winner. Raising an exception would break out of the s...
How to extract the decision rules from scikit-learn decision-tree?
...wer is more correct than the other answers here:
from sklearn.tree import _tree
def tree_to_code(tree, feature_names):
tree_ = tree.tree_
feature_name = [
feature_names[i] if i != _tree.TREE_UNDEFINED else "undefined!"
for i in tree_.feature
]
print "def tree({}):"....
How to avoid explicit 'self' in Python?
...e, and always know whether you are accessing a member or not:
class A(some_function()):
def f(self):
self.member = 42
self.method()
That's the complete code! (some_function returns the type used as a base.)
Another, where the methods of a class are dynamically composed:
class B(objec...
Python nested functions variable scoping [duplicate]
...When I run your code I get this error:
UnboundLocalError: local variable '_total' referenced before assignment
This problem is caused by this line:
_total += PRICE_RANGES[key][0]
The documentation about Scopes and Namespaces says this:
A special quirk of Python is that – if no global st...
How can i query for null values in entity framework?
...].[Foos] AS [Extent1]
WHERE (CASE
WHEN (([Extent1].[ProductID] = 1 /* @p__linq__0 */)
AND (NULL /* @p__linq__1 */ IS NOT NULL)) THEN
CASE
WHEN ([Extent1].[ProductStyleID] = NULL /* @p__linq__2 */) THEN cast(1 as bit)
WHEN ([Extent1].[ProductStyleID] <> NULL /* @p__li...
Oracle 11.2.0.4 RAC FOR redhat 6.4 - 数据库(内核) - 清泛网 - 专注C/C++及内核技术
...nt/iso/
mkdir -p /mnt/iso/oracle
使用SCP 工具 把 rhel-server-6.4-x86_64-dvd.iso 安装镜像上传到 服务器的 /mnt/iso/目录上传到 服务器的 /mnt/iso/目录
p13390677_112040_Linux-x86-64_1of7.zip
p13390677_112040_Linux-x86-64_2of7.zip
p13390677_112040_Linux-x86-64_3of7.zip
...
String concatenation vs. string substitution in Python
...e interpolation/templating.
>>> import timeit
>>> def so_q_sub(n):
... return "%s%s/%d" % (DOMAIN, QUESTIONS, n)
...
>>> so_q_sub(1000)
'http://stackoverflow.com/questions/1000'
>>> def so_q_cat(n):
... return DOMAIN + QUESTIONS + '/' + str(n)
...
>>> ...
Pythonic way to find maximum value and its index in a list?
...many options, for example:
import operator
index, value = max(enumerate(my_list), key=operator.itemgetter(1))
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How do I get the number of elements in a list?
...objects with a "size" in Python, in particular, have an attribute called ob_size, where the number of elements in the object is cached. So checking the number of objects in a list is very fast.
But if you're checking if list size is zero or not, don't use len - instead, put the list in a boolean co...