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How to create a numpy array of all True or all False?
...s very easily:
e.g. numpy.ones((2, 2)) or numpy.zeros((2, 2))
Since True and False are represented in Python as 1 and 0, respectively, we have only to specify this array should be boolean using the optional dtype parameter and we are done.
numpy.ones((2, 2), dtype=bool)
returns:
array([[ True, ...
Why does Python code use len() function instead of a length method?
...tocol in Python is to implement this method on objects which have a length and use the built-in len() function, which calls it for you, similar to the way you would implement __iter__() and use the built-in iter() function (or have the method called behind the scenes for you) on objects which are it...
Does a UNIQUE constraint automatically create an INDEX on the field(s)?
...managed to get that explain result, I've just copied your table definition and the same explain shows UNIQ_EMAIL_USER as possible key, can you please recheck it?
– piotrm
Mar 19 '12 at 3:01
...
Add number of days to a date
...time
expects to be given a string containing a US English date format and will try to parse that format into a Unix timestamp (the number of seconds since January 1 1970 00:00:00 UTC), relative to the timestamp given in now, or the current time if now is not supplied.
while date
Returns ...
What is the correct syntax for 'else if'?
... python "else if" is spelled "elif".
Also, you need a colon after the elif and the else.
Simple answer to a simple question. I had the same problem, when I first started (in the last couple of weeks).
So your code should read:
def function(a):
if a == '1':
print('1a')
elif a == '2...
How to read lines of a file in Ruby
...
I believe my answer covers your new concerns about handling any type of line endings since both "\r\n" and "\r" are converted to Linux standard "\n" before parsing the lines.
To support the "\r" EOL character along with the regular "\n", and "\r\n" from Windows, here's what I...
Grep characters before and after match?
...
3 characters before and 4 characters after
$> echo "some123_string_and_another" | grep -o -P '.{0,3}string.{0,4}'
23_string_and
share
|
im...
Set breakpoint in C or C++ code programmatically for gdb on Linux
... I don't know other debuggers, but gdb is pretty flexible about signal handling.
– Cascabel
Dec 1 '10 at 16:25
4
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Private module methods in Ruby
...
I think the best way (and mostly how existing libs are written) to do this is by creating a class within the module that deals with all the logic, and the module just provides a convenient method, e.g.
module GTranslate
class Translator
def...
Any implementation of Ordered Set in Java?
...Objective-C there is a collection called NSOrderedSet that acts as Set and its items can be accessed as an Array 's ones.
...