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Use of alloc init instead of new
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Very old question, but I've written some example just for fun — maybe you'll find it useful ;)
#import "InitAllocNewTest.h"
@implementation InitAllocNewTest
+(id)alloc{
NSLog(@"Allocating...");
return [super alloc];
}
-(id)init{
NSLog(@"Initializing...");
retur...
Cannot open include file 'afxres.h' in VC2010 Express
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123
Had the same problem . Fixed it by installing Microsoft Foundation Classes for C++.
Start
Ch...
How to convert int to QString?
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123
And if you want to put it into string within some text context, forget about + operator.
Simp...
How to copy a collection from one database to another in MongoDB
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You could do something like:
db.<collection_name>.find().forEach(function(d){ db.getSiblingDB('<new_database>')['<collection_name>'].insert(d); });
Please note that with this, the two databases would need to share the same mongod for this to work.
Besides this, you can do a...
Are +0 and -0 the same?
... Actually, this behavior models limit calculation in math. For example function 1/x has a value infinity in 0, however, it is separated if we are approaching 0 from the positive of negative side; in the former, the result is +inf, in the latter, -inf.
– Agoston Horvath
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Suppress warning messages using mysql from within Terminal, but password written in bash script
... edited Aug 4 at 7:44
coding is fun
35677 silver badges1515 bronze badges
answered Apr 8 '14 at 9:34
David Goo...
Big O, how do you calculate/approximate it?
...sertion sort
O(n3) - Multiplying two n×n matrices by simple algorithm
O(cn) - Finding the (exact) solution to the traveling salesman problem using dynamic programming; determining if two logical statements are equivalent using brute force
O(n!) - Solving the traveling salesman problem via brute-...
MySQL Query to select data from last week?
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123
SELECT id FROM tbl
WHERE date >= curdate() - INTERVAL DAYOFWEEK(curdate())+6 DAY
AND date &...
Test for equality among all elements of a single vector
...ing by the mean:
# Determine if range of vector is FP 0.
zero_range <- function(x, tol = .Machine$double.eps ^ 0.5) {
if (length(x) == 1) return(TRUE)
x <- range(x) / mean(x)
isTRUE(all.equal(x[1], x[2], tolerance = tol))
}
If you were using this more seriously, you'd probably want to...
How do I declare class-level properties in Objective-C?
...c variable? E.g. only one instance for all types of Foo?
To declare class functions in Objective-C you use the + prefix instead of - so your implementation would look something like:
// Foo.h
@interface Foo {
}
+ (NSDictionary *)dictionary;
// Foo.m
+ (NSDictionary *)dictionary {
static NSDict...