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Are string.Equals() and == operator really same? [duplicate]
...i.e. it can be overridden, and the implementation used will depend on the execution-time type of the target object), whereas the implementation of == used is determined based on the compile-time types of the objects:
// Avoid getting confused by interning
object x = new StringBuilder("hello").ToStr...
remove None value from a list without removing the 0 value
...
>>> L = [0, 23, 234, 89, None, 0, 35, 9]
>>> [x for x in L if x is not None]
[0, 23, 234, 89, 0, 35, 9]
Just for fun, here's how you can adapt filter to do this without using a lambda, (I wouldn't recommend this code - it's just for scientific purposes)
>>> f...
How do I change the value of a global variable inside of a function
...That's why it's considered best practice to always declare your variables explicitly with var. Because if you forget it, you can start messing with globals by accident. It's an easy mistake to make. But in your case, this turn around and becomes an easy answer to your question.
...
How can I read inputs as numbers?
Why are x and y strings instead of ints in the below code?
10 Answers
10
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Pan & Zoom Image
....RenderTransform;
double zoom = e.Delta > 0 ? .2 : -.2;
st.ScaleX += zoom;
st.ScaleY += zoom;
}
To handle the panning the first thing I did was to handle the MouseLeftButtonDown event on the image, to capture the mouse and to record it's location, I also store the current value of t...
How to concatenate twice with the C preprocessor and expand a macro as in “arg ## _ ## MACRO”?
...
Standard C Preprocessor
$ cat xx.c
#define VARIABLE 3
#define PASTER(x,y) x ## _ ## y
#define EVALUATOR(x,y) PASTER(x,y)
#define NAME(fun) EVALUATOR(fun, VARIABLE)
extern void NAME(mine)(char *x);
$ gcc -E xx.c
# 1 "xx.c"
# 1 "<built-in>"
# 1 "<...
What's the fastest way to merge/join data.frames in R?
For example (not sure if most representative example though):
5 Answers
5
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Checking for empty arrays: count vs empty
...s simply that something that should have happened, didn't happen: the non-existence of the member variable in the subclass was treated exactly the same way as though this member variable, an array, was empty — i.e., as though it had no elements). This is problematic, and another example of PHP bei...
Unable to load DLL 'SQLite.Interop.dll'
Periodically I am getting the following exception:
41 Answers
41
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Alternate output format for psql
...t needed to spend more time staring at the documentation. This command:
\x on
will do exactly what I wanted. Here is some sample output:
select * from dda where u_id=24 and dda_is_deleted='f';
-[ RECORD 1 ]------+---------------------------------------------------------------------------------...