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Why does comparing strings using either '==' or 'is' sometimes produce a different result?
...
One last thing to note, you may use the sys.intern function to ensure that you're getting a reference to the same string:
>>> from sys import intern
>>> a = intern('a')
>>> a2 = intern('a')
>>> a is a2
True
As pointed out abov...
What is a wrapper class?
...per.stringValue();
so this is the way , we can use wrapper class type to convert into other primitive types as well. This type of conversion is used when you need to convert a primitive type to object and use them to get other primitives as well.Though for this approach , you need to write a big c...
Calendar returns wrong month [duplicate]
...treal" ) );
int month = now.getMonthValue(); // Returns 1-12 as values.
Convert legacy classes
If you have a GregorianCalendar object in hand, convert to ZonedDateTime using new toZonedDateTime method added to the old class. For more conversion info, see Convert java.util.Date to what “java.ti...
Is there a built in function for string natural sort?
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Try this:
import re
def natural_sort(l):
convert = lambda text: int(text) if text.isdigit() else text.lower()
alphanum_key = lambda key: [ convert(c) for c in re.split('([0-9]+)', key) ]
return sorted(l, key = alphanum_key)
Output:
['elm0', 'elm1', 'Elm...
Showing the stack trace from a running Python application
...'s dump). Here is an implementation based on this blog:
import threading, sys, traceback
def dumpstacks(signal, frame):
id2name = dict([(th.ident, th.name) for th in threading.enumerate()])
code = []
for threadId, stack in sys._current_frames().items():
code.append("\n# Thread:...
Why does Python use 'magic methods'?
...those operations that
were generic for a group of types and
which were intended to work even for
objects that didn’t have methods at
all (e.g. tuples). It is also
convenient to have a function that can
readily be applied to an amorphous
collection of objects when you use the
functi...
Swift - How to convert String to Double
...g to write a BMI program in swift language.
And I got this problem: how to convert a String to a Double?
29 Answers
...
Using comparison operators in Scala's pattern matching system
...and a boolean expression after the pattern:
a match {
case 10 => println("ten")
case x if x > 10 => println("greater than ten")
case _ => println("less than ten")
}
Edit: Note that this is more than superficially different to putting an if after the =>, because a patter...
How to use GROUP BY to concatenate strings in SQL Server?
...
I ran into a couple of problems when I tried converting Kevin Fairchild's suggestion to work with strings containing spaces and special XML characters (&, <, >) which were encoded.
The final version of my code (which doesn't answer the original question but m...
What is cardinality in MySQL?
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Some columns are called high-cardinality columns because they have constraints in place (like unique) prohibiting you from putting the same value in every row.
Cardinality is a property which affects the ability to cluster, sort and search data. It is therefore an important measurement for the qu...