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How to switch position of two items in a Python list?
...assword1', 'first_name',
'last_name', 'next', 'newsletter']
a, b = i.index('password2'), i.index('password1')
i[b], i[a] = i[a], i[b]
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Changing the child element's CSS when the parent is hovered
...title>
<style>
.parent { display: block; position: relative; z-index: 0;
height: auto; width: auto; padding: 25px;
}
.parent-bg { display: block; height: 100%; width: 100%;
position: absolute; top: 0px; left: 0px;
border: 1px solid...
Cannot create an array of LinkedLists in Java…?
...will make LinkedList iterate 3000 times! Avoid LinkedList if anyone may be indexing into it. ArrayList will index faster, but Fredrik's solution is better overall.
– Steve Zobell
Mar 9 '17 at 20:08
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SQL SELECT WHERE field contains words
...
+ 1 I agree it's slower but it can be mitigated with good indexing
– Preet Sangha
Jan 12 '13 at 6:22
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The tilde operator in Python
...
One should note that in the case of array indexing, array[~i] amounts to reversed_array[i]. It can be seen as indexing starting from the end of the array:
[0, 1, 2, 3, 4, 5, 6, 7, 8]
^ ^
i ~i
...
Adding VirtualHost fails: Access Forbidden Error 403 (XAMPP) (Windows 7)
...; [..] </VirtualHost>.
After that, I added AllowOverride AuthConfig Indexes to the <Directory> options.
Now http://localhost also points to the dropbox-virtualhost. So I added dropbox.local to <VirtualHost *:80> which makes it as <VirtualHost dropbox.local:80>
FINALLY it w...
Storing time-series data, relational or non?
...ta"; it is selecting only the needed data. Yes, of course, if you have an Index to support the columns identified in the WHERE clause, it is very fast, and the query does not depend on the size of the table (grabbing 1,000 rows from a 16 billion row table is instantaneous).
Your table has one serio...
Delete the first three rows of a dataframe in pandas
...to do this in a groupby()? This works but returns duplicate columns in the index df=pd.DataFrame({'v':np.arange(10).tolist()*2,'g':['a']*10+['b']*10});df.groupby('g').apply(lambda x: x.iloc[3:])
– citynorman
Aug 6 '17 at 22:24
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Checking whether a variable is an integer or not [duplicate]
... check this.
Example (to do something every xth time in a for loop):
for index in range(y):
# do something
if (index/x.).is_integer():
# do something special
Edit:
You can always convert to a float before calling this method. The three possibilities:
>>> float(5).is_i...
Which is fastest? SELECT SQL_CALC_FOUND_ROWS FROM `table`, or SELECT COUNT(*)
...CALC_FOUND_ROWS?
Just a quick summary: Peter says that it depends on your indexes and other factors. Many of the comments to the post seem to say that SQL_CALC_FOUND_ROWS is almost always slower - sometimes up to 10x slower - than running two queries.
...