Question

我正在尝试根据几个条件进行关键词搜索。我的下面的代码创建了一些示例数据，并尝试通过它。它不喜欢ifelse，我相信因为GREP实际上并不返回真/假，而是实际数据。我想我必须创建一个子集，然后将其合并回去？但是，我似乎无法在带有GREP的子集中放置多个条件。

非常感谢任何帮助！

bus_name <- c('jacks wok shop'
               ,'jacks ski shop'
               ,'jacks wokshop'
               ,'jacks bakery'
               ,'jacks business'
               ,'jims Brewery'
               ,'jims Wok Brewery'
)
type <- c('restaurant'
             ,'restaurant'
             ,'restaurant'
             ,'restaurant'
             ,'office'
             ,'store'
             ,'building'
)

mydata <- data.frame(bus_name, type)

mydata$bus_name <- as.character(mydata$bus_name)
mydata$type <- as.character(mydata$type)


mydata$flag <- ifelse(mydata$type == "restaurant" & mydata[grep("WOK",toupper(mydata$bus_name)),],"Wok",
                      ifelse(mydata$type == "office" & mydata[grep("BUSINESS",toupper(mydata$bus_name)),],"Business","0"))

理想的输出如下：

bus_name|type|flag  
jacks wok shop|restaurant|Wok  
jacks ski shop|restaurant  
jacks wokshop|restaurant|Wok  
jacks bakery|restaurant  
jacks business|office|Business  
jims Brewery|store  
jims Wok Brewery|building|Wok

Answer 1

您必须使用if($result->num_rows > 0) { // you now know there are results while ($row = mysqli_fetch_assoc($result)) { // do your business in here as you would have, but you dont need to worry about nothing to process } } else { // do something in here to send back a null result, or whatever you like }来获取TRUE / FALSE的逻辑向量。您可以使用grepl中的case_when。它比嵌套的dplyr更容易阅读。

ifelse

Answer 2

如果您需要逻辑值，

grepl是要使用的函数。你需要这样的东西

mydata$flag <- ifelse(mydata$type == "restaurant" & grepl("WOK",toupper(mydata$bus_name)),
                              "Wok",
                      ifelse(mydata$type == "office" & grepl("BUSINESS",toupper(mydata$bus_name)),
                              "Business",""))

多条件关键字搜索

2 个答案: