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GroupBy pandas DataFrame and select most common value
...,'NY']})
source.groupby(['Country','City']).agg(lambda x:x.value_counts().index[0])
In case you are wondering about performing other agg functions in the .agg()
try this.
# Let's add a new col, account
source['account'] = [1,2,3,3]
source.groupby(['Country','City']).agg(mod = ('Short name', \...
Creating a new column based on if-elif-else condition
...B'], 'C'] = 1
df.loc[df['A'] < df['B'], 'C'] = -1
Easy to solve using indexing. The first line of code reads like so, if column A is equal to column B then create and set column C equal to 0.
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Meaning of Open hashing and Closed hashing
...e rest helps).
For instance, the "open" in "open addressing" tells us the index (aka. address) at which an object will be stored in the hash table is not completely determined by its hash code. Instead, the index may vary depending on what's already in the hash table.
The "closed" in "closed ha...
reducing number of plot ticks
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Only select first 3 datetime index. when get ax from pandas.DataFrame.plot ax = df.plot()
– Mithril
Nov 1 '19 at 2:27
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How to access custom attributes from event object in React?
... "event object" is still being passed. It's just NOT at the same parameter index it previously was. Binding in the fashion as outlined above is like unshifting the function arguments array. If the "event object" was at index 0 it would now be at index 1.
– Ryder Brooks
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Tags for Emacs: Relationship between etags, ebrowse, cscope, GNU Global and exuberant ctags
...the difference in more detail:
Point 1:
etags and ctags both generate an index (a.k.a. tag/TAGS) file of language objects found in source files that allows these items to be quickly and easily located by a text editor or other utility. A tag signifies a language object for which an index entry is ...
Using varchar(MAX) vs TEXT on SQL Server
...regard to if you should use LIKE to search, or if you should use Full Text Indexing and CONTAINS. This question is the same regardless of VARCHAR(MAX) or TEXT.
If you are searching large amounts of text and performance is key then you should use a Full Text Index.
LIKE is simpler to implement and ...
Rebasing a Git merge commit
...in/master]
* | e7affba 4
* | eb3b733 3
|/
* 38abeae 1
Let's get correct index now.
git checkout master # return to our master branch
git merge origin/master # merge origin/master on top of our master
We may get some additional merge conflicts here, but that's would only be conflicts from files...
How to install both Python 2.x and Python 3.x in Windows
...fine where the package should be installed:
http://docs.python.org/install/index.html#alternate-installation-windows-the-prefix-scheme
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WHERE vs HAVING
...range | value | value | 4 | NULL | 5 | Using where; Using index |
+----+-------------+-------+-------+---------------+-------+---------+------+------+--------------------------+
EXPLAIN SELECT `value` v FROM `table` having `value`>5;
+----+-------------+-------+-------+---------...