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Is the “struct hack” technically undefined behavior?
...nt to an object which can legally be interpreted as char [100]; inside the allocated object.
– R.. GitHub STOP HELPING ICE
Sep 14 '10 at 23:34
3
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Add single element to array in numpy
...your array should be fine. The drawback of this approach is that memory is allocated for a completely new array every time it is called. When growing an array for a significant amount of samples it would be better to either pre-allocate the array (if the total size is known) or to append to a list a...
get NSDate today, yesterday, this Week, last Week, this Month, last Month… variables
...UnitHour | NSCalendarUnitMinute | NSCalendarUnitSecond ) fromDate:[[NSDate alloc] init]];
[components setHour:-[components hour]];
[components setMinute:-[components minute]];
[components setSecond:-[components second]];
NSDate *today = [cal dateByAddingComponents:components toDate:[[NSDate alloc] ...
C++ performance vs. Java/C#
... lot of optimizations that just aren't safe.
Also Java and C# can do heap allocations more efficiently than C++ because the layer of abstraction between the garbage collector and your code allows it to do all of its heap compression at once (a fairly expensive operation).
Now I can't speak for Jav...
Creating an empty Pandas DataFrame, then filling it?
...op iterating through column names. In the former case, not only the memory allocation takes time, but replacing NaNs with new values seems extremely slow.
– deeenes
Mar 3 '15 at 16:33
...
Fatal error: unexpectedly found nil while unwrapping an Optional values [duplicate]
...r: String!) -> AnyObject! // Used by the delegate to acquire an already allocated cell, in lieu of allocating a new one.
That's determined by the exclamation mark after AnyObject:
AnyObject!
So, first thing to consider is, what is an "Implicitly Unwrapped Optional"?
The Swift Programmin...
Can we open pdf file using UIWebView on iOS?
... in your web view directly:
Objective-C
UIWebView *webView = [[UIWebView alloc] initWithFrame:CGRectMake(10, 10, 200, 200)];
NSURL *targetURL = [NSURL URLWithString:@"https://www.example.com/document.pdf"];
NSURLRequest *request = [NSURLRequest requestWithURL:targetURL];
[webView loadRequest:requ...
Does the default constructor initialize built-in types?
...tually a source for really strange errors as modern OSs tend to fill newly allocated memory regions with zeroes. If you expect that, it might work the first time. However, as your application keeps running, delete-ing and new-ing objects, you will sooner or later end up in a situation where you expe...
UITableView Cell selected Color?
...ed).
Therefore, if you're using a plain-style table, then you'll need to alloc-init a new UIView having your desired background colour and then assign it to selectedBackgroundView.
Alternatively, you could use:
cell.selectionStyle = UITableViewCellSelectionStyleGray;
if all you wanted was a gr...
How to populate/instantiate a C# array with a single value?
...ence, so it has to guess as to the array size. That means you'll get array allocations every time ToArray's buffer is exceeded, plus one more allocation at the end for the trim. There's also overhead involved with the enumerable object.
– Edward Brey
Feb 12 '16...