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Maximum size of an Array in Javascript
...a big deal
x=3e7 takes 1300ms, which is pretty bad
x=4e7 takes 11000ms and allocates an extra 2.5GB of memory
So around 30 million elements is a hard upper limit, because the javascript VM falls off a cliff at 40 million elements and will probably crash the process.
...
When should I use nil and NULL in Objective-C?
...e object. Let's have an example:
NSMutableArray *check = [[NSMutableArray alloc] init];
[check addObject:[NSNull null]];
[check addObject:nil];
On the second line, we will not get any error, because it is perfectly fair to insert a NSNull object into a collection type object. On the third line, w...
apc vs eaccelerator vs xcache
...ich were things under my control. 1) Don't let APC fill up. Make sure to allocate enough memory 2) Don't use apc_clear_cache() on an active server 3) APC doesn't really cope well with heavy lock contention -- don't try to write to a single key from multiple processes simultaneously.
...
How to convert a string into double and vice versa?
...separators, also.
NSNumberFormatter * myNumFormatter = [[NSNumberFormatter alloc] init];
[myNumFormatter setLocale:[NSLocale currentLocale]]; // happen by default?
[myNumFormatter setFormatterBehavior:NSNumberFormatterBehavior10_4];
// next line is very important!
[myNumFormatter setNumberStyle...
Zero-based month numbering [closed]
... pointer arithmetics where you would use one base pointer pointing at some allocated memory, plus a second pointer which would be at an offset from this base pointer. Here, using the value zero makes a lot of sense to point the offset to the base of the memory block. (General array logic tends to be...
Why (0-6) is -6 = False? [duplicate]
... is an array of 262 pointers to integer objects. Those integer objects are allocated during initialization in a block of integer objects we saw above. The small integers range is from -5 to 256. Many Python programs spend a lot of time using integers in that range so this is a smart decision.
This...
How to check if an NSDictionary or NSMutableDictionary contains a key?
...to a doesContain.
NSMutableDictionary* keysByName = [[NSMutableDictionary alloc] init];
keysByName[@"fred"] = @1;
NSString* test = @"fred";
if ([keysByName objectForKey:test] != nil)
NSLog(@"\nit works for key lookups"); // OK
else
NSLog(@"\nsod it");
if (keysByName[test] != nil)
NSL...
Convert between UIImage and Base64 string
...)decodeBase64ToImage:(NSString *)strEncodeData {
NSData *data = [[NSData alloc]initWithBase64EncodedString:strEncodeData options:NSDataBase64DecodingIgnoreUnknownCharacters];
return [UIImage imageWithData:data];
}
iOS 6.1 and < version
First Option : Use this link to encode and decode image...
How can I test if a letter in a string is uppercase or lowercase using JavaScript?
...
best answer by far, fast, not allocating any memory, or transforming data.
– Martijn Scheffer
Sep 6 '18 at 22:19
...
Html.Partial vs Html.RenderPartial & Html.Action vs Html.RenderAction
... as a MvcHtmlString and finally written to the output stream. Therefore it allocates a lot more memory.
– slfan
Mar 1 '17 at 13:09
2
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