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Change column type from string to float in Pandas
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You have four main options for converting types in pandas:
to_numeric() - provides functionality to safely convert non-numeric types (e.g. strings) to a suitable numeric type. (See also to_datetime() and to_timedelta().)
astype() - convert (almost) any type to (almost) any other type ...
What are best practices for validating email addresses on iOS 2.0
... *) candidate {
NSString *emailRegex =
@"(?:[a-z0-9!#$%\\&'*+/=?\\^_`{|}~-]+(?:\\.[a-z0-9!#$%\\&'*+/=?\\^_`{|}"
@"~-]+)*|\"(?:[\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x21\\x23-\\x5b\\x5d-\\"
@"x7f]|\\\\[\\x01-\\x09\\x0b\\x0c\\x0e-\\x7f])*\")@(?:(?:[a-z0-9](?:[a-"
@"z0-9-]*[a-z0-9])?\\.)+[a-z0-...
Chrome, Javascript, window.open in new tab
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As of 9/29/2014, latest Firefox ESR and IE 11 open _blank or window.open links in a new window when the js calls use _blank as the window name. Current Chrome isn't that simple. I tested opening a new window passing top, left, width, height, toolbar, location, directories, st...
Should I compile release builds with debug info as “full” or “pdb-only”?
...some of the differences between full and pdb-only. However, which is more appropriate for a release build? If I use "full" will there be performance ramifications? If I use "pdb-only" will it be harder to debug production issues?
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Android SDK installation doesn't find JDK
... Doesn't work for me on Windows 7 x64. I'm not joking. I set JAVA_HOME and I tried clicking back and next several times, but it's still not working. Neither does running SDK Manager.exe from the archive and I am positive I have JDK 7 installed (even ran the installer again and it told me i...
Using an ORM or plain SQL? [closed]
For some of the apps I've developed (then proceeded to forget about), I've been writing plain SQL, primarily for MySQL. Though I have used ORMs in python like SQLAlchemy , I didn't stick with them for long. Usually it was either the documentation or complexity (from my point of view) holding me b...
What is a “callback” in C and how are they implemented?
...y're implemented using function pointers. Here's an example:
void populate_array(int *array, size_t arraySize, int (*getNextValue)(void))
{
for (size_t i=0; i<arraySize; i++)
array[i] = getNextValue();
}
int getNextRandomValue(void)
{
return rand();
}
int main(void)
{
int m...
Why does the MongoDB Java driver use a random number generator in a conditional?
... laws it is a trivial observation that this piece of code amounts to
if (!_ok && Math.random() <= 0.1)
return res;
The commit that originally introduced this logic had
if (_ok == true) {
_logger.log( Level.WARNING , "Server seen down: " + _addr, e );
} else if (Math.random() < 0...
Modular multiplicative inverse function in Python
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If you happen to be using sympy, then x, _, g = sympy.numbers.igcdex(a, m) does the trick.
– Lynn
Sep 16 '16 at 18:15
add a comment
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What is the difference between String.Empty and “” (empty string)?
...private hidebysig instance string foo() cil managed
{
.maxstack 8
L_0000: ldstr "foo"
L_0005: ret
}
.method private hidebysig instance string bar() cil managed
{
.maxstack 8
L_0000: ldstr "bar"
L_0005: ldsfld string [mscorlib]System.String::Empty
L_000a: call string [msc...