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Stop Excel from automatically converting certain text values to dates
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In my MySQL query (for CSV output through PHP), I used CONCAT('\t', column_name). Also did the trick. Thanks!
– Just Plain High
Jun 24 '16 at 14:39
1
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Emacs bulk indent for Python
... region as normal, then:
C-x r t (string-rectangle): will prompt you for characters you'd like to insert into each line; great for inserting a certain number of spaces
C-x r k (kill-rectangle): remove a rectangle region; great for removing indentation
You can also C-x r y (yank-rectangle), but t...
How to check if a string in Python is in ASCII?
...so, then the original string is ASCII.
def isascii(s):
"""Check if the characters in string s are in ASCII, U+0-U+7F."""
return len(s) == len(s.encode())
To check, pass the test string:
>>> isascii("♥O◘♦♥O◘♦")
False
>>> isascii("Python")
True
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Using scanf() in C++ programs is faster than using cin?
...numbers.
iostream version:
#include <iostream>
int main(int argc, char **argv) {
int parity = 0;
int x;
while (std::cin >> x)
parity ^= x;
std::cout << parity << std::endl;
return 0;
}
scanf version:
#include <stdio.h>
int main(int argc, char **a...
What does void* mean and how to use it?
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Before void pointers were available "char *" was used instead. But void is better as it cannot actually be used to alter anything directly.
– user50619
Jun 4 '19 at 13:08
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RE error: illegal byte sequence on Mac OS X
...'s/./@/' <<<$'\xfc' fails, because byte 0xfc is not a valid UTF-8 char.
Note that, by contrast, GNU sed (Linux, but also installable on macOS) simply passes the invalid byte through, without reporting an error.
Using the formerly accepted answer is an option if you don't mind losing suppor...
Calling Objective-C method from C++ member function?
...d );
int doSomethingWith( void * aParameter );
void logMyMessage( char * aCStr );
private:
void * self;
};
#endif
Notice the wrapper methods no longer require the void pointer to an instance of MyClass; it is now a private member of MyClassImpl. The init method is used to instantia...
Convert pandas dataframe to NumPy array
...early the same (actually, using rec.fromrecords is a bit faster).
df2 = pd.concat([df] * 10000)
%timeit df2.to_records()
%%timeit
v = df2.reset_index()
np.rec.fromrecords(v, names=v.columns.tolist())
11.1 ms ± 557 µs per loop (mean ± std. dev. of 7 runs, 100 loops each)
9.67 ms ± 126 µs per l...
Creating C macro with ## and __LINE__ (token concatenation with positioning macro)
...or is expected to for decades. The prime example is compiling X11, macro "Concat3" is broken, it's result is now MISNAMED C Identifier, which of course fails to build. and i'm beginning to thing build fails are their profession.
I think the answer here is "new C that breaks standards is bad C", t...
Count the number of occurrences of a character in a string in Javascript
I need to count the number of occurrences of a character in a string.
33 Answers
33
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