key-value

So I have an RDD of something like this RDD[(Int, List)]] Where a single element in the RDD looks like (1, List(1, 2, 3)) My question is how can I expand the key value pair to something like this (1,1) (1,2) (1,3) Thank you rdd.flatMap { case (key, values) => values.map((key, _)) } etov And in Python (based on @seanowen's answer): rdd.flatMap(lambda x: map(lambda e: (x[0], e), x[1])) 来源： https://stackoverflow.com/questions/36392938/spark-expansion-of-rddkey-list-to-rddkey-value

I want to record a key-value in persistent mode but when I want to use 2 or more different stores it doesn't work. Here's my script: ... typedef struct{ kv_t *kv; char *name; } kv_data; int main(int argc, char *argv[]) { kv_data **data = (kv_data**)get_env(argv, US_SERVER_DATA); if(!data[0]){ data[0] = (kv_data*)calloc(1, sizeof(kv_data)); if(!data[0]){ return 500; } kv_t users; kv_init(&users, "users", 10, 0, 0, 0); data[0]->kv = &users; kv_item item; item.key = "pierre"; item.klen = sizeof("pierre") - 1; item.val = "pierre@example.com"; item.flags = 0; kv_add(data[0]->kv, &item); data[0]-

1. Map接口概述 Map与Collection并列存在。用于保存具有映射关系的数据：key-value； Map中的key和value都可以是任何应用类型的数据； Map中的key用Set来存放，不允许重复，即同一个Map对象所对应的类，须重写hashCode()和equals()方法； 常用String类作为Map的“键”； key和value之间存在单向一对一关系，即通过指定的key总能找到唯一的、确定的value； Map接口的常用实现类：HashMap、TreeMap、LinkedHashMap和Properties。其中HashMap是Map接口中使用频率最高的实现类。 1.1 Map接口：常用方法 添加、删除、修改操作 Object put(Object key, Object value)：将指定key-value添加到（或）修改当前map对象中； void putAll(Map m)：将m中的所有key-value对存放在当前的map中； Object remove(Object key)：移除指定key的key-value对，并返回value； void clear()：清空当前map中的所有数据。 元素查询的操作： Object get(Object key)：获得指定key对应的value； boolean containsKey(Object key)

在echarts的数据来源选型时，我在二维数组、对象数组两种形式中出现优于，看上去对象数组语义化挺好，但二维数组可以直接在echarts的各种例子里直接用，为了兼顾两个的长处，写了对象数组与二维数组的转换方法，代码如下（最外层花括号用于方便直接才控制台输出而不污染控制台环境）： { // 原始key-value形式的objArr let objArr=[ {product: 'Matcha Latte', count: 823, score: 95.8}, {product: 'Milk Tea', count: 235, score: 81.4}, {product: 'Cheese Cocoa', count: 1042, score: 91.2}, {product: 'Walnut Brownie', count: 988, score: 76.9} ]; // 目标值为二维数组arrArr let arrArr=[]; let dimensions=Object.keys(objArr[0]); console.log(dimensions); objArr.forEach((value,index)=>{ arrArr[index]=[]; dimensions.forEach(val => { arrArr[index].push(value[val]) }); })

I tried looking online everywhere for past hour, but I can't seem to figure out when to use colon operator : vs = operator in javascript? From what I can tell so far, it seems when defining object properties use colon : . The JavaScript language was built by Brandon Eich using the = sign as an assignment operator. Back in 1995, most programming languages, like Basic , Turbo Pascal , Delphi , C , C++ , etc... used the same method of assigning values to variables. Rapidly creating new objects in JavaScript using colons : became popular because of Douglas Crockford 's work in defining the JSON

The query part of a URL seems to consist of key-value pairs separated by & and associated by = . I've taken to always using jQuery's $.param() function to URL-encode my query strings because I find it makes my code more readable and maintainable. In the past couple of days I find myself calling the MediaWiki API but when cleaning up my working prototype with hard-coded URLs to use $.param() I noticed some MediaWiki APIs include query parameters with keys but not values! api.php ? action=query & titles=Main%20page & redirects Notice the part &redirects , which takes no value. jQuery's $.param()

How can I rename keys in an array? Start with this array named $start_array, [0] => [date] => 2012-05-01 [revenue] => 100 [1] => [date] => 2012-05-02 [revenue] => 200 and change the keys for 'date' and 'revenue' so you get this $final_array: [0] => [x] => 2012-05-01 [y] => 100 [1] => [x] => 2012-05-02 [y] => 200 Here is my terrible attempt which works but is messy. $final_array = array(); $max = count($start_array); for ($j = 0; $j < $max; $j++) { $final_array[] = array('x' => $start_array[$j]['dateid'], 'y' => $start_array[$j]['ctrl_version_revenue'] ); } hjpotter92 foreach( $start_array as &

I have a dictionary and I would like to get some values from it based on some keys. For example, I have a dictionary for users with their first name, last name, username, address, age and so on. Let's say, I only want to get one value (name) - either last name or first name or username but in descending priority like shown below: (1) last name: if key exists, get value and stop checking. If not, move to next key. (2) first name: if key exists, get value and stop checking. If not, move to next key. (3) username: if key exists, get value or return null/empty #my dict looks something like this