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How to get the last N rows of a pandas DataFrame?
... dataframe df1 and df2 (df1 is vanila dataframe, df2 is indexed by 'STK_ID' & 'RPT_Date') :
3 Answers
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Explanation of strong and weak storage in iOS5
... storage. I have read the documentation and other SO questions, but they all sound identical to me with no further insight.
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Difference between fold and reduce?
...
So basically instead of doing fold, you can simply add that initial value to the start of the list and do reduce? What's the point of fold then?
– Pacerier
Feb 7 '17 at 9:42
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How to merge YAML arrays?
...hon:3.7.3
stage: test
script:
- *pip_git
- pip install -q -r requirements_test.txt
- python -m unittest discover tests
use the same `*pip_git` on e.g. build image...
where requirements_test.txt contains e.g.
-e git+ssh://git@gitlab.com/example/example.git@v0.2.2#e...
Cost of len() function
...
Calling len() on those data types is O(1) in CPython, the most common implementation of the Python language. Here's a link to a table that provides the algorithmic complexity of many different functions in CPython:
TimeComple...
Python: Using .format() on a Unicode-escaped string
...gt; print s
≥
>>> print "{0}".format(s)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
UnicodeEncodeError: 'ascii' codec can't encode character u'\u2265' in position 0: ordinal not in range(128)
>>> print u"{0}".format(s)
≥
>>>
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Determine if an object property is ko.observable
...ce) {
if ((instance === null) || (instance === undefined) || (instance.__ko_proto__ === undefined)) return false;
if (instance.__ko_proto__ === ko.dependentObservable) return true;
return ko.isComputed(instance.__ko_proto__); // Walk the prototype chain
};
UPDATE: If you are using KO 2...
How to open every file in a folder?
...
Os
You can list all files in the current directory using os.listdir:
import os
for filename in os.listdir(os.getcwd()):
with open(os.path.join(os.cwd(), filename), 'r') as f: # open in readonly mode
# do your stuff
Glob
Or you c...
How can I split and parse a string in Python?
I am trying to split this string in python: 2.7.0_bf4fda703454
3 Answers
3
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Initializing a static std::map in C++
... Every time I see something like that done with C++, I think of all the horrendous template code that must be behind it. Good example!
– Greg Hewgill
Sep 26 '08 at 10:22
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