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Filter rows which contain a certain string
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263
The answer to the question was already posted by the @latemail in the comments above. You can ...
How to get the first column of a pandas DataFrame as a Series?
...>>> import pandas as pd
>>> df = pd.DataFrame({'x' : [1, 2, 3, 4], 'y' : [4, 5, 6, 7]})
>>> df
x y
0 1 4
1 2 5
2 3 6
3 4 7
>>> s = df.ix[:,0]
>>> type(s)
<class 'pandas.core.series.Series'>
>>>
================================...
Splitting a list into N parts of approximately equal length
... equal parts? For example, if the list has 7 elements and is split it into 2 parts, we want to get 3 elements in one part, and the other should have 4 elements.
...
Can you supply arguments to the map(&:method) syntax in Ruby?
...h will enable you to do not only this:
a = [1,3,5,7,9]
a.map(&:+.with(2))
# => [3, 5, 7, 9, 11]
But also a lot of other cool stuff, like passing multiple parameters:
arr = ["abc", "babc", "great", "fruit"]
arr.map(&:center.with(20, '*'))
# => ["********abc*********", "********babc...
Operation on every pair of element in a list
...
233
Check out product() in the itertools module. It does exactly what you describe.
import itert...
Emulate ggplot2 default color palette
What function can I use to emulate ggplot2's default color palette for a desired number of colors. For example, an input of 3 would produce a character vector of HEX colors with these colors:
...
What is the fastest method for selecting descendant elements in jQuery?
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Method 1 and method 2 are identical with the only difference is that method 1 needs to parse the scope passed and translate it to a call to $parent.find(".child").show();.
Method 4 and Method 5 both need to parse the selector and then just cal...
What is the difference between tinyint, smallint, mediumint, bigint and int in MySQL?
...ation:
MySQL
Postgres
Oracle (they just have a NUMBER datatype really)
DB2
Turns out they all use the same specification (with a few minor exceptions noted below) but support various combinations of those types (Oracle not included because it has just a NUMBER datatype, see the above link):
...
How does numpy.histogram() work?
...s aren't of equal width) of each bar.
In this example:
np.histogram([1, 2, 1], bins=[0, 1, 2, 3])
There are 3 bins, for values ranging from 0 to 1 (excl 1.), 1 to 2 (excl. 2) and 2 to 3 (incl. 3), respectively. The way Numpy defines these bins if by giving a list of delimiters ([0, 1, 2, 3]) in...
Java: how can I split an ArrayList in multiple small ArrayLists?
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332
You can use subList(int fromIndex, int toIndex) to get a view of a portion of the original list....