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How can I count the occurrences of a list item?
...ple items. Calling count in a loop requires a separate pass over the list for every count call, which can be catastrophic for performance. If you want to count all items, or even just multiple items, use Counter, as explained in the other answers.
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Prepend a level to a pandas MultiIndex
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A nice way to do this in one line using pandas.concat():
import pandas as pd
pd.concat([df], keys=['Foo'], names=['Firstlevel'])
An even shorter way:
pd.concat({'Foo': df}, names=['Firstlevel'])
This can be generalized to many data frames, see the docs.
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How to alter a column and change the default value?
I got the following error while trying to alter a column's data type and setting a new default value:
7 Answers
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How can I disable logging while running unit tests in Python Django?
...ng.CRITICAL)
will disable all logging calls with levels less severe than or equal to CRITICAL. Logging can be re-enabled with
logging.disable(logging.NOTSET)
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How are booleans formatted in Strings in Python?
...ic to boolean values - %r calls the __repr__ method on the argument. %s (for str) should also work.
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What replaces cellpadding, cellspacing, valign, and align in HTML5 tables?
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/* cellpadding */
th, td { padding: 5px; }
/* cellspacing */
table { border-collapse: separate; border-spacing: 5px; } /* cellspacing="5" */
table { border-collapse: collapse; border-spacing: 0; } /* cellspacing="0" */
/* valign */
th, td { vertical-align: top; }
/* align (center) */
table ...
How can I get the timezone name in JavaScript?
...set, but what I need is the ability to detect something like "America/New York." Is that even possible from JavaScript or is that something I am going to have to guestimate based on the offset?
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Android RelativeLayout programmatically Set “centerInParent”
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Completely untested, but this should work:
View positiveButton = findViewById(R.id.positiveButton);
RelativeLayout.LayoutParams layoutParams =
(RelativeLayout.LayoutParams)positiveButton.getLayoutParams();
layoutParams.addRule(RelativeLayout.CENTER_IN_PAREN...
I don't remember my android debug.keystore password
How can i see my debug.keystore password?
I entered my password 3 or 4 month ago and now i don't remember.
4 Answers
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How to detect current state within directive
...t;@bilbobaggins</a>
</li>
<!-- ... -->
</ul>
Or filters:
"stateName" | isState & "stateName" | includedByState
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