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Performance of foreach, array_map with lambda and array_map with static function

...W, I just did the benchmark since poster didn't do it. Running on PHP 5.3.10 + XDebug. UPDATE 2015-01-22 compare with mcfedr's answer below for additional results without XDebug and a more recent PHP version. function lap($func) { $t0 = microtime(1); $numbers = range(0, 1000000); $ret = $f...
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Convert an image to grayscale in HTML/CSS

.../* Disable grayscale on hover */ img:hover { -webkit-filter: grayscale(0); filter: none; } <img src="http://lorempixel.com/400/200/"> What about Internet Explorer 10? You can use a polyfill like gray. ...
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Hide separator line on one UITableViewCell

...-1){ UIImageView *line = [[UIImageView alloc] initWithFrame:CGRectMake(0, 44, 320, 2)]; line.backgroundColor = [UIColor redColor]; [cell addSubview:line]; } for iOS 7 upper versions (including iOS 8) if (indexPath.row == self.newCarArray.count-1) { cell.separatorInset = UIEdgeInse...
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how to convert array values from string to int?

... | edited Apr 23 '19 at 10:46 Rahul 16.8k77 gold badges3434 silver badges5353 bronze badges answered Ma...
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搭建高可用mongodb集群(四)—— 分片 - 大数据 & AI - 清泛网 - 专注C/C++及内核技术

...了,安装软件! 1、准备机器,IP分别设置为: 192.168.0.136、192.168.0.137、192.168.0.138。 2、分别在每台机器上建立mongodb分片对应测试文件夹。 #存放mongodb数据文件 mkdir -p /data/mongodbtest #进入mongodb文件夹 cd /data/mongodbtest 3...
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How can I add a box-shadow on one side of an element?

...the box-shadow rule: .myDiv { border: 1px solid #333; width: 100px; height: 100px; box-shadow: 10px 0 5px -2px #888; } <div class="myDiv"></div> The fourth property there -2px is the shadow spread, you can use it to change the spread of the shadow, making it a...
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Is this a “good enough” random algorithm; why isn't it used if it's faster?

... QuickRandom qr = new QuickRandom(); int[] frequencies = new int[10]; for (int i = 0; i < 100000; i++) { frequencies[(int) (qr.random() * 10)]++; } printDistribution("QR", frequencies); frequencies = new int[10]; for (int i = 0; i <...
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std::vector performance regression when enabling C++11

...ck(Item());) $ g++ -std=c++11 -O3 -flto regr.cpp && perf stat -r 10 ./a.out Performance counter stats for './a.out' (10 runs): 35.426793 task-clock # 0.986 CPUs utilized ( +- 1.75% ) 4 context-switches # 0.116 K/sec ...
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Black transparent overlay on image hover with only CSS?

... the img element itself, see. .image { position: relative; width: 400px; height: 400px; } Give the child img element a width of 100% of the parent and add vertical-align:top to fix the default baseline alignment issues. .image img { width: 100%; vertical-align: top; } As for th...
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Find integer index of rows with NaN in pandas dataframe

...MultiIndex that you can use to index back into df, e.g.: df['a'].ix[index[0]] >>> 1.452354 For the integer index: df_index = df.index.values.tolist() [df_index.index(i) for i in index] >>> [3, 6] share...