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Slicing of a NumPy 2d array, or how do I extract an mxm submatrix from an nxn array (n>m)?
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answered Nov 23 '10 at 16:07
Justin PeelJustin Peel
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How to check if a column exists in Pandas
... not present in df
– Robvh
Feb 5 at 10:59
add a comment
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When does invoking a member function on a null instance result in undefined behavior?
...d. (Notes are non-normative.)
However, one can try to deduced it from §3.10/2:
An lvalue refers to an object or function.
When dereferencing, the result is an lvalue. A null pointer does not refer to an object, therefore when we use the lvalue we have undefined behavior. The problem is that...
“INSERT IGNORE” vs “INSERT … ON DUPLICATE KEY UPDATE”
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1003
I would recommend using INSERT...ON DUPLICATE KEY UPDATE.
If you use INSERT IGNORE, then the...
Reference — What does this symbol mean in PHP?
..., then the increment/decrement operation is done.
For example:
$apples = 10;
for ($i = 0; $i < 10; ++$i) {
echo 'I have ' . $apples-- . " apples. I just ate one.\n";
}
Live example
In the case above ++$i is used, since it is faster. $i++ would have the same results.
Pre-increment is a l...
Android preferences onclick event
...s handled else false.
– Thupten
Oct 10 '17 at 1:10
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Calculate relative time in C#
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1005
Jeff, your code is nice but could be clearer with constants (as suggested in Code Complete).
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How do you print in a Go test using the “testing” package?
...Something
Say hi
--- PASS: TestPrintSomething (0.00 seconds)
v_test.go:10: Say bye
PASS
ok so/v 0.002s
Command go
Description of testing flags
-v
Verbose output: log all tests as they are run. Also print all
text from Log and Logf calls even if the test succeeds.
Pac...
Map Tiling Algorithm
...ingrobert king
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Can I use conditional statements with EJS templates (in JMVC)?
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StanleyZhengStanleyZheng
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