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Adding new column to existing DataFrame in Python pandas
... because if you have multiple rows, and you use the assignment, it assigns all rows of the new column with that value ( in your case e) which is usually undesirable.
– Paniz
Apr 27 '19 at 22:42
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Thread-safe List property
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ConcurrentBag doesn't implement IList and is not actually thread safe version of List
– Vasyl Zvarydchuk
Apr 3 '17 at 20:55
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MySQL query String contains
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Quite simple actually:
mysql_query("
SELECT *
FROM `table`
WHERE `column` LIKE '%{$needle}%'
");
The % is a wildcard for any characters set (none, one or many). Do note that this can get slow on very large datasets so if your database grow...
Python logging: use milliseconds in time format
...d of a struct_time, then (at least with modern versions of Python) we can call ct.strftime and then we can use %f to format microseconds:
import logging
import datetime as dt
class MyFormatter(logging.Formatter):
converter=dt.datetime.fromtimestamp
def formatTime(self, record, datefmt=None...
unbound method f() must be called with fibo_ instance as first argument (got classobj instance inste
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OK, first of all, you don't have to get a reference to the module into a different name; you already have a reference (from the import) and you can just use it. If you want a different name just use import swineflu as f.
Second, you are...
Can a variable number of arguments be passed to a function?
...able to pass any number of arguments.
def manyArgs(*arg):
print "I was called with", len(arg), "arguments:", arg
>>> manyArgs(1)
I was called with 1 arguments: (1,)
>>> manyArgs(1, 2, 3)
I was called with 3 arguments: (1, 2, 3)
As you can see, Python will unpack the arguments...
How to get the Power of some Integer in Swift language?
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I really like this solution, but with Swift 3 it does not work. Any idea how to make it work?
– Vanya
Sep 19 '16 at 18:51
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How do I best silence a warning about unused variables?
I have a cross platform application and in a few of my functions not all the values passed to functions are utilised. Hence I get a warning from GCC telling me that there are unused variables.
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PHP: exceptions vs errors?
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Exceptions are thrown - they are intended to be caught. Errors are generally unrecoverable. Lets say for instance - you have a block of code that will insert a row into a database. It is possible that this call fails (duplicate ID) - you will want to have a "Error" which in this case is an "Exc...
Convert objective-c typedef to its string equivalent
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This is really a C question, not specific to Objective-C (which is a superset of the C language). Enums in C are represented as integers. So you need to write a function that returns a string given an enum value. There are many ways to...