data_frame%>%mutate(Price_status=case_when(Price>=500000&Price<=900000~"Average",Price>900000~"High",TRUE~"Low")) 输出: 方法2:使用Case when语句处理NA 再次查看我们在上面创建的 data_frame 的 Price 列。有些汽车的价格值等于 NA。在应用 case_when() 函数时,必须小心处理。 R 为我们提供了 is...
# Like an if statement, the arguments are evaluated in order, so you must # proceed from the most specific to the most general. This won't work: case_when( TRUE ~ as.character(x), x %% 5 == 0 ~ "fizz", x %% 7 == 0 ~ "buzz", x %% 35 == 0 ~ "fizz buzz" ) #> [...
# Like an if statement, the arguments are evaluated in order, so you must # proceed from the most specific to the most general. This won't work:case_when(TRUE ~ as.character(x),x %% 5 == 0 ~ "fizz",x %% 7 == 0 ~ "buzz",x %% 35 == 0 ~ "fizz buzz")#> [1] "...
Notice as well the final line of the case_when statement. The final lineTRUE ~ 'F'effectively assigns the value 'F' as an "else" value, if none of the previous conditions wereTRUE. EXAMPLE 3: Use case_when to do if-else, and create a new variable in a dataframe Next, we're goin...
[49] "buzz" "fizz"# Like an if statement, the arguments are evaluated in order, so you must# proceed from the most specific to the most general. This won't work:case_when(TRUE~as.character(x),x%%5==0~"fizz",x%%7==0~"buzz",x%%35==0~"fizz buzz")#> [1] "1" "2" "3...
原SQL如下:SQL的主要问题是红色部分居然通过标量查询,反复的查找与SQL相同的基表,很显然这个可以用case when来简化。 select a.TRAN_ID, a.AMOUNT, a.BALANCE, a.INVAMT, a.PROMISED, a.INVNO, a.RCLNUM, b.PROBLEM_ID, a.TRANTYPE, a.TYPE, ...
在Oracle数据库中,'CASE WHEN'语法用于根据条件执行不同的操作或返回不同的值。它类似于其他编程语言中的条件语句,可以帮助我们在查询或更新数据时进行灵活的处理。 'CASE WHEN'语法的基本结构如下: 代码语言:txt 复制 CASE WHEN condition1 THEN result1 WHEN condition2 THEN result2 ... ELSE resultN ...
在编程中,SQL(结构化查询语言)是一种用于管理关系数据库的语言。它允许用户查询、插入、更新和删除数据库中的数据。在SQL中,可以使用CASE-WHEN语句来根据特定条件对数据进行条件性处理。 当需...
possible. Aggregate expressions that appear in WHEN arguments to a CASE statement are evaluated first, then provided to the CASE statement. For example, the following query produces a divide by zero error when producing the value of the MAX aggregate. This occurs prior to evaluating the CASE ...
Like SQL "case when" statement and Swith statement from popular programming languages, Spark SQL Dataframe also supports similar syntax using "when otherwise" or we can also use "case when" statement.