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How to detect a Christmas Tree? [closed]
... can be broken down into about 3 steps. First I apply a threshold (or actually, the logical "or" of two separate and distinct thresholds). As with many of the other answers, I assumed that the Christmas tree would be one of the brighter objects in the scene, so the first threshold is just a simple...
How much is the overhead of smart pointers compared to normal pointers in C++?
..._ptr always has memory overhead for reference counter, though it is very small.
std::unique_ptr has time overhead only during constructor (if it has to copy the provided deleter and/or null-initialize the pointer) and during destructor (to destroy the owned object).
std::shared_ptr has time overhe...
How to debug heap corruption errors?
...nctionality was in Application Verifier.
Electric Fence (aka "efence"), dmalloc, valgrind, and so forth are all worth mentioning, but most of these are much easier to get running under *nix than Windows. Valgrind is ridiculously flexible: I've debugged large server software with many heap issues u...
How can i tell if an object has a key value observer attached
...
Put a try catch around your removeObserver call
@try{
[someObject removeObserver:someObserver forKeyPath:somePath];
}@catch(id anException){
//do nothing, obviously it wasn't attached because an exception was thrown
}
...
Do I have to guard against SQL injection if I used a dropdown?
... make sure the posted size is what you expect.
$possibleOptions = array('All', 'Large', 'Medium', 'Small');
if(in_array($_POST['size'], $possibleOptions)) {
// Expected
} else {
// Not Expected
}
Then use mysqli_* if you are using a version of php >= 5.3.0 which you should be, to sav...
Swift - Split string over multiple lines
... some text
over multiple lines
"""
Older versions of Swift don't allow you to have a single literal over multiple lines but you can add literals together over multiple lines:
var text = "This is some text\n"
+ "over multiple lines\n"
...
How does this checkbox recaptcha work and how can I use it?
...
Excerpt from the email: We expect to move all existing reCAPTCHA sites to the new API in 2015.
– Timothy Zorn
Sep 11 '14 at 3:29
1
...
Why is semicolon allowed in this python snippet?
...ot warrant the use of semicolons to end statements.
So why is this (below) allowed?
15 Answers
...
Get selected value in dropdown list using JavaScript
...options[e.selectedIndex].value;
Would make strUser be 2. If what you actually want is test2, then do this:
var e = document.getElementById("ddlViewBy");
var strUser = e.options[e.selectedIndex].text;
Which would make strUser be test2
...
Is there an exponent operator in C#?
...o in most programs, and
it doesn't seem justified to add an
operator when calling Math.Pow() is
simple.
You asked:
Do I have to write a loop or include
another namespace to handle
exponential operations? If so, how do
I handle exponential operations using
non-integers?
Math.Pow supports double p...