Returning a particular index of a list based on another index of the same list R -

i have list below(this 1 element of list there 50 more every state)

$ak                                        hospital.name state   heartattack  heartfailure     pneumonia 99                  providence alaska medical center    ak          13.4          12.4           7.9 103                         alaska regional hospital    ak          14.5          13.4           8.9 102                      fairbanks memorial hospital    ak          15.5          15.6           9.8 106                     alaska native medical center    ak          15.7          11.6          11.6 100                   mat-su regional medical center    ak          17.7          11.4           9.0 104               yukon kuskokwim delta reg hospital    ak not available          11.2           6.9 110                         sitka community hospital    ak not available not available           7.8 114 peacehealth ketchikan medical             center    ak not available          11.4           8.0 101                       bartlett regional hospital    ak not available          11.6           8.1 113                   norton sound regional hospital    ak not available not available           8.1 111             providence kodiak island medical ctr    ak not available not available           8.2 115                         south peninsula hospital    ak not available          10.8           8.5 107                            mt edgecumbe hospital    ak not available not available           9.6 105               central peninsula general hospital    ak not available          11.6           9.8 108                 providence valdez medical center    ak not available not available not available 109                       providence seward hospital    ak not available not available not available 112                 cordova community medical center    ak not available not available not available 

i trying bring-out hospitals has less heartattack rate across list.

so when write function work on first element of list , call

  test <- function(x){     if(x[[1]][,3] == min(x[[1]][,3]))       return(head(x[[1]][1],1))    }  test(statedata) 

it seems work fine below warning

(warning message: in if (x[[1]][, 3] == min(x[[1]][, 3])) return(head(x[[1]][1], 1)) :   condition has length > 1 , first element used)                         hospital.name 99 providence alaska medical center 

but when try use same function code inside lapply loop through entire list element not seem work , fails below issue

result <- lapply(statedata,function(statedata) if(statedata[[1]][,3] == min(statedata[[1]][,3])) return(head(statedata[[1]][1],1)) )  error in statedata[[1]][, 3] : incorrect number of dimensions 

not sure if missing lapply??

that's right because you're masking global variable statedata function parameter statedata. better way be:

statedata = lapply(statedata, function(s) {  s[!is.na(as.integer(s$heartattack)),,drop=f] }) wm = which.min(sapply(statedata, function(s) min(s$heartattack))) wstate = statedata[[wm]] wstate[which.min(wstate$heartattack), "hospital"] 

the first lapply remove "not available" hospitals, next sapply find worst state, , worst state used grab worst hospital in worst state.