r - 如何在 R 中将“列表”转换为“EUtilisSUmmary”类

Answer 1

lapply 返回一个对象列表，这些对象的类由调用的函数定义

library(RISmed)
library(rentrez)
library(dplyr)
search_topic <- c("KRAS AND MEK inhibitor","BRAF AND BRAF inhibitor")
search_query <- lapply((search_topic),EUtilsSummary, retmax=50, 
                       mindate=2000, maxdate=2017) 

在这种情况下search_query，是一个列表 ( class(search_query)，其中包含类 EUtilsSummary 的对象class(search_query[[1]])。

要在列表中操作此类对象，只需将另一个对象lapply与可以将它们作为参数的函数一起使用：

lapply(search_query, QueryId)
#output:
[[1]]
 [1] "29079711" "29067643" "28982179" "28982154" "28957417" "28938614" "28866094" "28807001" "28797845" "28783173"
[11] "28775144" "28746882" "28619758" "28581516" "28574828" "28554329" "28551618" "28492898" "28459468" "28372922"
[21] "28301591" "28248226" "28215705" "28178529" "28167505" "28154798" "28152546" "28062115" "28060183" "28002807"
[31] "27997540" "27922010" "27876675" "27846317" "27834733" "27822414" "27821484" "27803104" "27793696" "27167191"
[41] "27733477" "27699948" "27670374" "27496137" "27484466" "27469379" "27467210" "27441499" "27422710" "27399335"

[[2]]
 [1] "29100459" "29098416" "29096034" "29094484" "29085667" "29084636" "29079332" "29074209" "29072975" "29070145"
[11] "29066909" "29059158" "29054724" "29050517" "29050239" "29050218" "29048432" "29043205" "29040023" "29028954"
[21] "29028788" "28994264" "28991513" "28986666" "28984520" "28984291" "28984141" "28982601" "28982154" "28981385"
[31] "28979142" "28978720" "28976960" "28973166" "28963969" "28963614" "28961465" "28960564" "28959611" "28951457"
[41] "28947956" "28939558" "28936920" "28931905" "28923537" "28923400" "28919996" "28918496" "28915798" "28893027"