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How to get method parameter names?
...k at the inspect module - this will do the inspection of the various code object properties for you.
>>> inspect.getfullargspec(a_method)
(['arg1', 'arg2'], None, None, None)
The other results are the name of the *args and **kwargs variables, and the defaults provided. ie.
>>>...
How do I format a date with Dart?
I have an instance of DateTime and I would like to format that to a String. How do I do that? I want to turn the date into a string, something like "2013-04-20".
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Using Python 3 in virtualenv
Using virtualenv , I run my projects with the default version of Python (2.7). On one project, I need to use Python 3.4.
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Convert python datetime to epoch with strftime
...ert a python datetime to seconds since epoch you could do it explicitly:
>>> (datetime.datetime(2012,04,01,0,0) - datetime.datetime(1970,1,1)).total_seconds()
1333238400.0
In Python 3.3+ you can use timestamp() instead:
>>> datetime.datetime(2012,4,1,0,0).timestamp()
1333234800...
Rename column SQL Server 2008
I am using SQL Server 2008 and Navicat. I need to rename a column in a table using SQL.
11 Answers
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Use '=' or LIKE to compare strings in SQL?
...ee the performance difference, try this:
SELECT count(*)
FROM master..sysobjects as A
JOIN tempdb..sysobjects as B
on A.name = B.name
SELECT count(*)
FROM master..sysobjects as A
JOIN tempdb..sysobjects as B
on A.name LIKE B.name
Comparing strings with '=' is much faster.
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Apply a function to every row of a matrix or a data frame
Suppose I have a n by 2 matrix and a function that takes a 2-vector as one of its arguments. I would like to apply the function to each row of the matrix and get a n-vector. How to do this in R?
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Finding ALL duplicate rows, including “elements with smaller subscripts”
...nt of a vector or data frame is a duplicate of an element with a smaller subscript. So if rows 3, 4, and 5 of a 5-row data frame are the same, duplicated will give me the vector
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Sort rows in data.table in decreasing order on string key `order(-x,v)` gives error on data.table 1.
Let's say I have the following data.table in R :
3 Answers
3
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EF Migrations: Rollback last applied migration?
This looks like a really common task, but I can't find an easy way to do it.
14 Answers
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