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Collection that allows only unique items in .NET?
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answered Mar 1 '11 at 17:12
DonutDonut
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Add column with number of days between dates in DataFrame pandas
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df['A'] = pd.to_datetime(df['A'])
df['B'] = pd.to_datetime(df['B'])
In [11]: df.dtypes # if already datetime64 you don't need to use to_datetime
Out[11]:
A datetime64[ns]
B datetime64[ns]
dtype: object
In [12]: df['A'] - df['B']
Out[12]:
one -58 days
two -26 days
dtype: timedelta64[ns...
How to copy from CSV file to PostgreSQL table with headers in CSV file?
I want to copy a CSV file to a Postgres table. There are about 100 columns in this table, so I do not want to rewrite them if I don't have to.
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How to create a shared library with cmake?
...PTION (this latter variable necessitate cmake 3.9):
project(mylib VERSION 1.0.1 DESCRIPTION "mylib description")
Declare a new library target. Please avoid the use of file(GLOB ...). This feature does not provide attended mastery of the compilation process. If you are lazy, copy-paste output of l...
Error - trustAnchors parameter must be non-empty
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One-liner to check whether an iterator yields at least one element?
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any won't go beyond the first element if it's True. In case the iterator yields something fals...
How to get duplicate items from a list using LINQ? [duplicate]
...var duplicates = lst.GroupBy(s => s)
.SelectMany(grp => grp.Skip(1));
Note that this will return all duplicates, so if you only want to know which items are duplicated in the source list, you could apply Distinct to the resulting sequence or use the solution given by Mark Byers.
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How to install Android SDK Build Tools on the command line?
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How can I use map and receive an index as well in Scala?
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148
I believe you're looking for zipWithIndex?
scala> val ls = List("Mary", "had", "a", "littl...
Rounding BigDecimal to *always* have two decimal places
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