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Linq: What is the difference between Select and Where
The Select and Where methods are available in Linq. What should every developer know about these two methods? For example: when to use one over the other, any advantages of using one over the other, etc.
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Why does GCC generate such radically different assembly for nearly the same C code?
...I've managed to see how GCC optimizes the first case.
Before we can understand why they are so different, first we must understand how GCC optimizes fast_trunc_one().
Believe it or not, fast_trunc_one() is being optimized to this:
int fast_trunc_one(int i) {
int mantissa, exponent;
mantissa...
How to overcome TypeError: unhashable type: 'list'
...e split the file on `x`, since the part before the x will be
# the key and the part after the value
line = line.split('x')
# Take the line parts and strip out the spaces, assigning them to the variables
# Once you get a bit more comfortable, this works as well:
# key, value = [x....
Iterate a list with indexes in Python
...ve seen the function (or method) that takes a list, like this [3, 7, 19] and makes it into iterable list of tuples, like so: [(0,3), (1,7), (2,19)] to use it instead of:
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Python's “in” set operator
... Ok so "is there an element x in s such that hash(b) == hash(x) and x == b"?
– Dejas
Jan 2 '12 at 21:25
13
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Is there a Java standard “both null or equal” static method?
To save some typing and clarify my code, is there a standard version of the following method?
3 Answers
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Change values while iterating
... prints you completely different memory locations for the value from range and the actual
value in the slice:
0xf84000f010 vs. 0x7f095ed0bf68
0xf84000f014 vs. 0x7f095ed0bf68
0xf84000f018 vs. 0x7f095ed0bf68
So the only thing you can do is to either use pointers or the index, as already proposed ...
How to get one value at a time from a generator function in Python?
...thon 3.x
In Python >= 2.6, use next(gen). This is a built in function, and is clearer. It will also work in Python 3.
Both of these end up calling a specially named function, next(), which can be overridden by subclassing. In Python 3, however, this function has been renamed to __next__(), to b...
What is %2C in a URL?
I'm trying to understand the structure of a URL, and I'm seeing a lot of %2C . I'm guessing this is a result of some encoding. What does that stand for?
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Matplotlib Legends not working
...uple of line objects, no matter how many are actually created from the command. Without the comma, "plot1" and "plot2" are tuples instead of line objects, making the later call to plt.legend() fail.
The comma implicitly unpacks the results so that instead of a tuple, "plot1" and "plot2" automatica...