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What is the most efficient way to create a dictionary of two pandas Dataframe columns?
..._dict()[VALUE]
Proof on 50,000 rows:
df = pd.DataFrame(np.random.randint(32, 120, 100000).reshape(50000,2),columns=list('AB'))
df['A'] = df['A'].apply(chr)
%timeit dict(zip(df.A,df.B))
%timeit pd.Series(df.A.values,index=df.B).to_dict()
%timeit df.set_index('A').to_dict()['B']
Output:
100 loop...
'const string' vs. 'static readonly string' in C#
...pocrite. ;)
– LukeH
Nov 18 '12 at 1:32
What about performance in case of strings in particular? Will each const usage ...
sqlite alter table add MULTIPLE columns in a single statement
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edited Feb 8 '17 at 14:32
Community♦
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32
In JavaScript: (START)[\s\S]*(END) - See www.regexpal.com to test
– Zymotik
Jul 15 '14 at 15:40
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nwinklernwinkler
43.5k1818 gold badges132132 silver badges149149 bronze badges
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MYSQL Dump only certain rows
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32
You need to quote the "where" clause.
Try
mysqldump --opt --user=username --password=passwor...
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davidfowldavidfowl
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running Rails console in production
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edited Feb 28 '13 at 18:32
answered Feb 28 '13 at 18:22
j...
How to initialize all members of an array to the same value?
... VAL_8X VAL_4X, VAL_4X
#define VAL_16X VAL_8X, VAL_8X
#define VAL_32X VAL_16X, VAL_16X
#define VAL_64X VAL_32X, VAL_32X
int myArray[53] = { VAL_32X, VAL_16X, VAL_4X, VAL_1X };
If you need to change the value, you have to do the replacement at only one place.
Edit: possible useful ...