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count the frequency that a value occurs in a dataframe column
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Use groupby and count:
In [37]:
df = pd.DataFrame({'a':list('abssbab')})
df.groupby('a').count()
Out[37]:
a
a
a 2
b 3
s 2
[3 rows x 1 columns]
See the online docs: http://pandas.pydata.org/pandas-docs/stable/groupby.html
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Why use finally in C#?
...d regardless of whether or not there is an exception. This comes in very handy when it comes to certain housekeeping functions you need to always run like closing connections.
Now, I'm guessing your question is why you should do this:
try
{
doSomething();
}
catch
{
catchSomething();
}
f...
CSS3 box-sizing: margin-box; Why not?
...is highly browser-dependant. Probably around 2020 the ie15 will support it and you will be allowed to use that in your work, too :-(
– peterh - Reinstate Monica
Nov 25 '13 at 10:32
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How to cast/convert pointer to reference in C++
...pr 16 '12 at 10:53
David HeffernanDavid Heffernan
560k3939 gold badges935935 silver badges13421342 bronze badges
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How can I see all the issues I'm watching on Github?
Github has a great feature where you can "watch" an issue. This is handy for getting notifications about progress on that issue.
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Base64: What is the worst possible increase in space usage?
If a server received a base64 string and wanted to check it's length before converting,, say it wanted to always permit the final byte array to be 16KB. How big could a 16KB byte array possibly become when converted to a Base64 string (assuming one byte per character)?
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Laravel orderBy on a relationship
...ed this, it doesn't work. Here's my case : I have two table (appointments and schedules), the query is simple : get appointments order by schedules.datetime descending. I have solution by adding new column in table appointments to store datetime from table schedules. And now I only need to order by...
How to read environment variables in Scala
... answered Apr 3 '12 at 17:01
andyandy
1,64511 gold badge99 silver badges77 bronze badges
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Is there a limit to the length of HTML attributes?
... So the answer should be "unlimited" then?
– Anders Lindén
Aug 11 '15 at 14:41
2
Thank y...
C++: How to round a double to an int? [duplicate]
...xact: It has plenty of digits to store some fractional part you add to it. And it's especially true of 0.5, which is a power of two.
– Ruslan
Jul 15 '16 at 12:03
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