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Pandas selecting by label sometimes return Series, sometimes returns DataFrame
... other ways, but in my opinion this is the cleanest.
In [2]: type(df.loc[[3]])
Out[2]: pandas.core.frame.DataFrame
In [3]: type(df.loc[[1]])
Out[3]: pandas.core.frame.DataFrame
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Check if an element is present in an array [duplicate]
...ecifically solves the problem, and so is now the preferred method.
[1, 2, 3].includes(2); // true
[1, 2, 3].includes(4); // false
[1, 2, 3].includes(1, 2); // false (second parameter is the index position in this array at which to begin searching)
As of JULY 2018, this has been implement...
How to normalize an array in NumPy?
...
3
Thanks for the answer but are you sure that sklearn.preprocessing.normalize works also with vector of shape=(n,) or (n,1) ? I am having som...
Google Maps API v3: How do I dynamically change the marker icon?
Using Google Maps API v3, how do I programmatically change the marker icon?
5 Answers
...
Is a Python list guaranteed to have its elements stay in the order they are inserted in?
...nd places it behind the content of another.
If we have
list1 = [0, 1, 2, 3, 4]
list2 = [5, 6, 7, 8, 9]
Then
list1 + list2
Is the same as
[0, 1, 2, 3, 4] + [5, 6, 7, 8, 9]
Which evaluates to
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
Much like
"abdcde" + "fghijk"
Produces
"abdcdefghijk"
...
What does |= (ior) do in Python?
...
53
|= performs an in-place+ operation between pairs of objects. In particular, between:
sets: a u...
Identifying the dependency relationship for python packages installed with pip
...e [installed: 0.18]
- itsdangerous [required: >=0.21, installed: 0.23]
alembic==0.6.2
- SQLAlchemy [required: >=0.7.3, installed: 0.9.1]
- Mako [installed: 0.9.1]
- MarkupSafe [required: >=0.9.2, installed: 0.18]
ipython==2.0.0
slugify==0.0.1
redis==2.9.1
To get it run:
pip i...
List comprehension vs map
...:
$ python -mtimeit -s'xs=range(10)' 'map(hex, xs)'
100000 loops, best of 3: 4.86 usec per loop
$ python -mtimeit -s'xs=range(10)' '[hex(x) for x in xs]'
100000 loops, best of 3: 5.58 usec per loop
An example of how performance comparison gets completely reversed when map needs a lambda:
$ pytho...
How to fix the uninitialized constant Rake::DSL problem on Heroku?
...
answered Jun 7 '11 at 9:31
KaleKale
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How to sort a list in Scala by two fields?
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seniasenia
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