array

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: Given a table that contains a column of JSON like this: {"payload":[{"type":"b","value":"9"}, {"type":"a","value":"8"}]} {"payload":[{"type":"c","value":"7"}, {"type":"b","value":"3"}]} How can I write a Presto query to give me the average b value across all entries? So far I think I need to use something like Hive's lateral view explode , whose equivalent is cross join unnest in Presto. But I'm stuck on how to write the Presto query for cross join unnest . How can I use cross join unnest to expand all array elements and select them? 回答1: As

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: if([] == false) alert('empty array is false'); alert(+[]) // alert 0 if([]) alert('empty array is true'); They both will run the alert Demo 回答1: Both current answers here are correct, but I'd like to add a more detalied explanation based on the language specification . The reason for the apparently contradictory outcomes is that if statements and equality comparisons are evaluated differently. In the case of an if(expression) statement, the expression is evaluated and then converted to the boolean type ( § 12.5 ). Arrays are Objects, and

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I have two arrays of maps 1st is [{:a 1 :b 2 :d 6} {:a 2 :b 2} {:a 7 :b 7}] 2nd is [{:a 3 :c 3 :e 9 :y 7} {:a 2 :b 6 :c 8}] depending on the value of a i.e. if its matches in 2nd array the '2nd map' should be merged with '1st map' and the resultant array of maps should be Res should be [{:a 1 :b 2 :d 6} {:a 2 :b 6 :c 8} {:a 7 :b 7} {:a 3 :c 3 :e 9 :y 7}] Can anyone help me on this. Thanks in advance. 回答1: Here you go: user> (def xs [{:a 1 :b 2 :d 6} {:a 2 :b 2} {:a 7 :b 7}]) #'user/xs user> (def ys [{:a 3 :c 3 :e 9 :y 7} {:a 2 :b 6 :c 8}]) #

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 由 翻译 强力驱动 问题: So I am not sure exactly what I would have to show you guys, how ever if you need more code please do not hesitate to ask: So this method will set up the initMailer for Zend with in our application: protected function _initMailer () { if ( 'testing' !== APPLICATION_ENV ) { $this -> bootstrap ( 'Config' ); $options = $this -> getOptions (); $mail = new Zend_Application_Resource_Mail ( $options [ 'mail' ]); } elseif ( 'testing' === APPLICATION_ENV ) { //change the mail transport only if dev or test if ( APPLICATION_ENV 'production' )

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I am newbie in Perl and I am reading about arrays. As I understand the arrays expand automatically as needed (cool!) But I also read that we can use negative indexes to access the arrays in reverse order. E.g. an array of 3 elements can be accessed as: $array[0] $array[1] $array[2] or $array[-1] $array[-2] $array[-3] (in reverse order). My question is what happens for values smaller than -3 e.g. $array[-5] ? Does the array expand or something? 回答1: If you read it, the result is the same as reading $array[5] ― the value doesn't exist and you

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I have this: <?php $n = rand(1,1600); echo $n ?> I want to exclude from random numbers let's say 234, 1578 ,763 , 1274 and other numbers. How would I do that? 回答1: <?php while( in_array( ($n = rand(1,1600)), array(234, 1578 ,763 , 1274) ) ); 回答2: Try like this do { $n = rand(1,1600); } while(in_array($n, array(234, 1578 ,763 , 1274 )); echo $n; 回答3: Check if the number is one that you don't want, if it is get a new random number. function getRandomNumber() { do { $n = mt_rand(1,1600); } while(in_array($n, array(234,1578, 763, 1274))); return

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I'm writing a script that plots some data with dates on the x axis (in matplotlib). I need to create a numpy.linspace out of those dates in order to create a spline afterwards. Is it possible to do that? What I've tried: import datetime import numpy as np dates = [ datetime.datetime(2015, 7, 2, 0, 31, 41), datetime.datetime(2015, 7, 2, 1, 35), datetime.datetime(2015, 7, 2, 2, 37, 9), datetime.datetime(2015, 7, 2, 3, 59, 16), datetime.datetime(2015, 7, 2, 5, 2, 23)] x = np.linspace(min(dates), max(dates), 500) It throws this error: TypeError:

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I am confuse as how to pass variable from controller to view. I know there is a lot about this already on stockoverflow but unable to find one that works, please point me in the right direction. Thank you. CONTROLLER class StoreController extends Controller { public function index() { $store = Store::all(); // got this from database model return view('store', $store); } { VIEW // try a couple of differnt things nothing works print_r($store); print_r($store[0]->id); print_r($id); 回答1: public function index() { $store = Store::all(); // got

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I've been upgrading a project to use Realm as the persistence store and I'm not able to find any documentation on how to use an array of strings in one of my models. The implementation of an Array for a RLMObject is to use an RLMArray where T inherits RLMObject I could make an object that inherits.. property inside which is string... but that seems like quite some overhead to replace an NSArray of strings. Does anyone know the recommended best practice to do this? 回答1: As of Realm Cocoa 3.0 you can simply do RLMArray<RLMString> *array; and

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: Can I store ^block in a dictionary or an array? I need to listen to a server notification which I need to provide a block to handle the notification, and in my project several view controllers all want to hear the notification, so I made a generic notification manager, which has its own block for handling server notification and it has an array of delegates, so in the manager's block: - (^)(NSString *message){ for (delegate in allDelegates) { delegate.handlerBlock(message); } } but can I store blocks in a collection? 回答1: You can store