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How to append contents of multiple files into one file
... should be >> right ? and also why is there a newline before all the text in my 0.txt file ?
– Steam
Aug 2 '13 at 0:00
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ImportError in importing from sklearn: cannot import name check_build
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Worked for me after installing scipy.
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How does an underscore in front of a variable in a cocoa objective-c class work?
...to-generated accessor (for the property) knows which ivar to use. Specifically, in your implementation file, your synthesize should look like this:
@synthesize missionName = _missionName;
More generically, this is:
@synthesize propertyName = _ivarName;
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Assigning a variable NaN in python without numpy
...aking) be said to be equal to one another -- see What is the rationale for all comparisons returning false for IEEE754 NaN values? for more details and information.
Instead, use math.isnan(...) if you need to determine if a value is NaN or not.
Furthermore, the exact semantics of the == operation...
Get names of all keys in the collection
I'd like to get the names of all the keys in a MongoDB collection.
21 Answers
21
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C++ multiline string literal
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const char *text2 =
"Here, on the other hand, I've gone crazy \
and really let the literal span several lines, \
without bothering with quoting each line's \
content. This works, but you can't indent.";
Again, note those backslashes at the end of each line, they must be immediately before the...
SQL Server - copy stored procedures from one db to another
...you tick the top-level checkbox beside "Stored Procedures" it selects them all together - 1 click.
– Barry Kaye
May 22 '12 at 14:06
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What is the use of “assert” in Python?
...t True # nothing happens
>>> assert False
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AssertionError
Assertions can include an optional message, and you can disable them when running the interpreter.
To print a message if the assertion fails:
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PHP array_filter with arguments
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As an alternative to @Charles's solution using closures, you can actually find an example in the comments on the documentation page. The idea is that you create an object with the desired state ($num) and the callback method (taking $i as an argument):
class LowerThanFilter {
private ...
Any reason not to use '+' to concatenate two strings?
... Tuple would be faster - the code was just an example :) Usually long multiple string inputs are dynamic.
– Mikko Ohtamaa
Apr 6 '12 at 12:52
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