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select count(*) from table of mysql in php
...2
Kermit
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answered Aug 2 '11 at 5:48
Shakti SinghSh...
Why does this Java code compile?
...
nneonneonneonneo
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...
Print multiple arguments in Python
... isn't a function in Python 2. You can, however, import this behavior from __future__:
from __future__ import print_function
Use the new f-string formatting in Python 3.6:
print(f'Total score for {name} is {score}')
sha...
Creating a Pandas DataFrame from a Numpy array: How do I specify the index column and column headers
...u could do it like this:
import pandas
import numpy
dtype = [('Col1','int32'), ('Col2','float32'), ('Col3','float32')]
values = numpy.zeros(20, dtype=dtype)
index = ['Row'+str(i) for i in range(1, len(values)+1)]
df = pandas.DataFrame(values, index=index)
...
What is RSS and VSZ in Linux memory management
... binary then:
RSS: 400K + 1000K + 100K = 1500K
VSZ: 500K + 2500K + 200K = 3200K
Since part of the memory is shared, many processes may use it, so if you add up all of the RSS values you can easily end up with more space than your system has.
The memory that is allocated also may not be in RSS un...
Why does i = i + i give me 0?
...
The issue is due to integer overflow.
In 32-bit twos-complement arithmetic:
i does indeed start out having power-of-two values, but then overflow behaviors start once you get to 230:
230 + 230 = -231
-231 + -231 = 0
...in int arithmetic, since it's essentially ari...
Getting the first character of a string with $str[0]
...ng multibyte encodings (such as UTF-8). If you want to support that, use mb_substr(). Arguably, you should always assume multibyte input these days, so this is the best option, but it will be slightly slower.
share
...
How does the main() method work in C?
... be handled. */
extern int main(int argc, char **argv, char **envp);
void __start(void)
{
/* This is the real startup function for the executable.
It performs a bunch of library initialization. */
/* ... */
/* And then: */
exit(main(argc_from_somewhere, argv_from_somewhere, envp_from...
How to use Git?
...
answered Jun 17 '09 at 4:32
dragonflydragonfly
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...
Is there a function to make a copy of a PHP array to another?
... by reference. This means that:
$a = array();
$b = $a;
$b['foo'] = 42;
var_dump($a);
Will yield:
array(0) {
}
Whereas:
$a = new StdClass();
$b = $a;
$b->foo = 42;
var_dump($a);
Yields:
object(stdClass)#1 (1) {
["foo"]=>
int(42)
}
You could get confused by intricacies such as Ar...