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How do I search for an object by its ObjectId in the mongo console?
...ay to change your "scope" or something at the command line and not really know it?
– jcollum
Nov 22 '11 at 20:36
No wo...
Find out how much memory is being used by an object in Python [duplicate]
...ld you go about finding out how much memory is being used by an object? I know it is possible to find out how much is used by a block of code, but not by an instantiated object (anytime during its life), which is what I want.
...
Determine if variable is defined in Python [duplicate]
How do you know whether a variable has been set at a particular place in the code at runtime? This is not always obvious because (1) the variable could be conditionally set, and (2) the variable could be conditionally deleted. I'm looking for something like defined() in Perl or isset() in PHP or...
How do you test that a Python function throws an exception?
...ust alias that as unittest:
import unittest2 as unittest
Example tests
Now, paste into your Python shell the following test of Python's type-safety:
class MyTestCase(unittest.TestCase):
def test_1_cannot_add_int_and_str(self):
with self.assertRaises(TypeError):
1 + '1'
...
Pandas convert dataframe to array of tuples
I have manipulated some data using pandas and now I want to carry out a batch save back to the database. This requires me to convert the dataframe into an array of tuples, with each tuple corresponding to a "row" of the dataframe.
...
C++ sorting and keeping track of indexes
...p;v](size_t i1, size_t i2) {return v[i1] < v[i2];});
return idx;
}
Now you can use the returned index vector in iterations such as
for (auto i: sort_indexes(v)) {
cout << v[i] << endl;
}
You can also choose to supply your original index vector, sort function, comparator, or ...
Parameterize an SQL IN clause
...f int[] (document/SQL keys) and then the code above comes in. The whole OP now takes less than 200ms :)
– Fredrik Johansson
May 3 '13 at 6:57
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What does “dereferencing” a pointer mean?
...ate, see "More about memory addresses, and why you probably don't need to know" at the end of this answer.
When you want to access the data/value in the memory that the pointer points to - the contents of the address with that numerical index - then you dereference the pointer.
Different computer...
Navigation bar appear over the views with new iOS7 SDK
...hod.
Note: You should be using the latest GM release of iOS 7 and Xcode 5 now since the API has changed from beta versions.
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Useful code which uses reduce()? [closed]
...The other uses I've found for it besides + and * were with and and or, but now we have any and all to replace those cases.
foldl and foldr do come up in Scheme a lot...
Here's some cute usages:
Flatten a list
Goal: turn [[1, 2, 3], [4, 5], [6, 7, 8]] into [1, 2, 3, 4, 5, 6, 7, 8].
reduce(list...