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What is the syntax rule for having trailing commas in tuple definitions?
...
That's a simple answer.
a = ("s") is a string
and
a = ("s",) is a tuple with one element.
Python needs an additional comma in case of one element tuple to, differentiate between string and tuple.
For example try this on python console:
a = ("s")
a = a + (1,...
Meaning of numbers in “col-md-4”,“ col-xs-1”, “col-lg-2” in Bootstrap
...ey are used to define at which screen size that class should apply:
xs = extra small screens (mobile phones)
sm = small screens (tablets)
md = medium screens (some desktops)
lg = large screens (remaining desktops)
Read the "Grid
Options"
chapter from the official Bootstrap documentation f...
In JavaScript, why is “0” equal to false, but when tested by 'if' it is not false by itself?
...the comparison is performed.
When you do: if ("0") console.log("ha"), the string value is being tested. Any non-empty string is true, while an empty string is false.
Equal (==)
If the two operands are not of the same type, JavaScript converts the operands then applies strict comparison. If...
Get name of object or class
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And this will return empty string, if used on objects declared through variable: var Foo = function() {};.
– Aleksandr Makov
Feb 26 '14 at 14:56
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How to convert a String to CharSequence?
How to convert String to CharSequence in Java?
5 Answers
5
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Is it faster to count down than it is to count up?
...culative instructions will sneak in the "Sub i and N" without incurring an extra cycle -- and -- even the crudest compiler will optimise the the "Sub i and N" out of existence.
– James Anderson
May 13 '10 at 5:47
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A non well formed numeric value encountered
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Because you are passing a string as the second argument to the date function, which should be an integer.
string date ( string $format [, int $timestamp = time() ] )
Try strtotime which will Parse about any English textual datetime description i...
Multiple columns index when using the declarative ORM extension of sqlalchemy
...me__ = 'table_A'
id = Column(Integer, primary_key=True)
a = Column(String(32), index=True)
b = Column(String(32), index=True)
if you'd like a composite index, again Table is present here as usual you just don't have to declare it, everything works the same (make sure you're on recent 0...
How to Query an NTP Server using C#?
...rver using C# to get the Date Time of the NTP Server returned as either a string or as a DateTime .
6 Answers
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Selecting multiple columns in a pandas dataframe
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The column names (which are strings) cannot be sliced in the manner you tried.
Here you have a couple of options. If you know from context which variables you want to slice out, you can just return a view of only those columns by passing a list into the...