blocks|key|1439134|text|据我所知，这是在NSArray中放置浮点数的一种非常有效的方法。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1439135|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

As far as I know, this is a perfectly valid way of putting floats in an NSArray.

blocks|key|1439186|text|我同意mouviciel的观点。由于您不能将简单类型放入数组中，因此这是实现此目的的方法。看起来有点奇怪，而且要写很多代码，但它很好。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1439187|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

I agree with mouviciel. Since you can't put simple types into an Array this is the way to do it. Looks a bit strange and is a lot of code to write but it is fine.

blocks|key|1439211|text|稍微偏离正题，如果你只想存储一个浮点数组，并且不真正需要NSArray或NSNumber的附加功能，那么你也应该考虑一个标准的C数组：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1439212|float+fatArray[]+=+{6.6,+6.9,+4.7,+6.9};|code-block|syntax|javascript|1439213|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

going off on a slight tangent, if all you want to do is store an array of floats and don't really need the added functionality of an NSArray or NSNumber, then you should also consider just a standard C array:

<pre><code>float fatArray[] = {6.6, 6.9, 4.7, 6.9};
</code></pre>

blocks|key|1224438|text|如果您要创建大量具有完全相同数量的元素的此类数组，则可以定义一个FloatArrayFactory类来实现以下内容：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1224439|%2B+(NSArray+*)+arrayWithFloat:+(float)f;
%2B+(NSArray+*)+arrayWithFloat:+(float)f1+and:+(float)f2;
%2B+(NSArray+*)+arrayWithFloat:+(float)f1+and:+(float)f2+and:+(float)f3;
%2B+(NSArray+*)+arrayWithFloat:+(float)f1+and:+(float)f2+and:+(float)f3+and:+(float)f4;|code-block|syntax|javascript|1224440|如果这太过冗长，你可以使用简洁而时髦的未命名参数：|1224441|%2B+(NSArray+*)+arr:+(float)f1+:+(float)f2+:+(float)f3;|1224442|你可以这样调用它：|1224443|NSArray+*a+=+[Factory+arr:+1.0+:2.0+:3.0+:4.0];|1224444|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|U|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

If you're going to be creating a lot of these arrays with exactly the same number of elements, you could define a FloatArrayFactory class that implements something like:

<pre><code>+ (NSArray *) arrayWithFloat: (float)f;
+ (NSArray *) arrayWithFloat: (float)f1 and: (float)f2;
+ (NSArray *) arrayWithFloat: (float)f1 and: (float)f2 and: (float)f3;
+ (NSArray *) arrayWithFloat: (float)f1 and: (float)f2 and: (float)f3 and: (float)f4;
</code></pre>

And if that's too verbose, you could go for the terse and funky look of unnamed parameters:

<pre><code>+ (NSArray *) arr: (float)f1 : (float)f2 : (float)f3;
</code></pre>

which you can call like this:

<pre><code>NSArray *a = [Factory arr: 1.0 :2.0 :3.0 :4.0];
</code></pre>

blocks|key|1439275|text|如果您有许多浮点数要转换，或者想要从逗号分隔的列表中粘贴它们，那么调用一个将浮点数转换为NSArray实例的函数可能会更容易。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1439276|NSArray*++arrayFromFloats(NSUInteger+count,+float+*floats)
{
++++NSMutableArray*+ma+=+[NSMutableArray+arrayWithCapacity:count];+
++++NSUInteger+i;+
++++for+(i=0;+i<count;+i%2B%2B)+{+
++++++++[ma+addObject:[NSNumber+numberWithFloat:floats[i]]];
++++}
++++return+(NSArray*)ma;+
}|code-block|syntax|javascript|1439277|示例调用者：|1439278|static+float+floats[]+=+{1.1,+2.2,+3.3};+
NSUInteger+count+=+sizeof(floats)/sizeof(float);
NSArray*+a+=+arrayFromFloats(count,+floats);+|1439279|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

If you have a lot of floats to convert, or want to paste them in from a comma separated list, it may be easier to call a function that converts floats into an NSArray instance. 

<pre><code>NSArray* arrayFromFloats(NSUInteger count, float *floats)
{
 NSMutableArray* ma = [NSMutableArray arrayWithCapacity:count]; 
 NSUInteger i; 
 for (i=0; i&lt;count; i++) { 
 [ma addObject:[NSNumber numberWithFloat:floats[i]]];
 }
 return (NSArray*)ma; 
}
</code></pre>

Example caller: 

<pre><code>static float floats[] = {1.1, 2.2, 3.3}; 
NSUInteger count = sizeof(floats)/sizeof(float);
NSArray* a = arrayFromFloats(count, floats); 
</code></pre>

blocks|key|1224558|text|另一个懒惰的选择是只使用NSStrings数组，然后直接从字符串中获取要查找的值的类型。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1224559|如下所示：|1224560|NSArray+*arrayOfNumbers+=+[NSArray+arrayWithObjects:@"3.12",@"3.2",+@"12",+@"15",+nil];
float+number+=+[[arrayOfNumbers+objectAtIndex:0]+floatValue];|code-block|syntax|javascript|1224561|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|L|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|M|8|@]|9|@]|A|$G|H]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Another lazy option is to just use an array of NSStrings and then getting the type of value you are looking for directly from the string.

Like so:

<pre><code>NSArray *arrayOfNumbers = [NSArray arrayWithObjects:@"3.12",@"3.2", @"12", @"15", nil];
float number = [[arrayOfNumbers objectAtIndex:0] floatValue];
</code></pre>

Is this a valid way to initalize an NSArray with float objects?

<pre><code>NSArray *fatArray = [NSArray arrayWithObjects:
 [NSNumber numberWithFloat:6.9],
 [NSNumber numberWithFloat:4.7],
 [NSNumber numberWithFloat:6.6],
 [NSNumber numberWithFloat:6.9],nil];
</code></pre>

It works and it feels right, just wanted to make sure I was on the right track.

gary

Initialize NSArray with floats?

这是用浮点对象初始化NSArray的有效方法吗？NSArray *fatArray = [NSArray arrayWithObjects:                    [NSNumber numberWithFloat:6.9],                    [NSNumber numberWit...

问是否使用浮点数初始化NSArray？
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