dataframe - Counting back to events in R -

-

how count years since happened in r? data looks this:

                 year  fatal  non-fatal french airline   1989    1       1  french airline   1990    1       0  french airline   1991    0       0 french airline   1992    0       1 french airline   1993    0       0 uk airline       1989    1       1 uk airline       1990    0       0 uk airline       1991    1       0 uk airline       1992    0       0 uk airline       1993    0       0

grouped airline, want have column counts when last fatal, or non-fatal crash happened. output this:

                 year  fatal  non-fatal  since fatal  since non-fatal                french airline   1989    1       1           0              0 french airline   1990    1       0           0              1 french airline   1991    0       0           1              2 french airline   1992    0       1           2              0  french airline   1993    0       0           3              1 uk airline       1989    1       1           0              0  uk airline       1990    0       0           1              1 uk airline       1991    1       0           0              2 uk airline       1992    0       0           1              3 uk airline       1993    0       0           2              4

in ideal world i'd have column @ end counts kind of crash, fatal or non-fatal. how do it?

using joins , requiring version 1.9.7+ of package:

library(data.table)  # data borrowed @majom's answer  d[, sf :=    d[as.logical(fatal)][d, on=.(airline, year), roll=true, year-x.year]]  d[, sn :=    d[as.logical(non_fatal)][d, on=.(airline, year), roll=true, year-x.year]]  d[, sa :=    d[as.logical(pmax(fatal, non_fatal))][d, on=.(airline, year), roll=true, year-x.year]]

which gives

           airline year fatal non_fatal sf sn sa  1: french_airline 1989     1         1  0  0  0  2: french_airline 1990     1         0  0  1  0  3: french_airline 1991     0         0  1  2  1  4: french_airline 1992     0         1  2  0  0  5: french_airline 1993     0         0  3  1  1  6:     uk_airline 1989     1         1  0  0  0  7:     uk_airline 1990     0         0  1  1  1  8:     uk_airline 1991     1         0  0  2  0  9:     uk_airline 1992     0         0  1  3  1 10:     uk_airline 1993     0         0  2  4  2

alternately, last one: d[, sa := pmin(sf, sn)] if you've computed those.

the coercion logical should hint cols ought stored logical already...


Comments

Post a Comment

Popular posts from this blog

Spring Boot + JPA + Hibernate: Unable to locate persister -

-
i trying work entity inside request method of spring boot application. entity in project , pom.xml has dependencies it. why error message?: org.hibernate.unknownentitytypeexception: unable locate persister: com.ric.bill.model.bs.par package com.ric.web; import java.util.concurrent.atomic.atomiclong; import javax.persistence.entitymanager; import javax.persistence.persistencecontext; import net.sf.ehcache.cachemanager; import net.sf.ehcache.management.cache; import net.sf.ehcache.management.cachestatistics; import org.hibernate.stat.statistics; import org.springframework.beans.factory.annotation.autowired; import org.springframework.boot.autoconfigure.domain.entityscan; import org.springframework.cache.annotation.enablecaching; import org.springframework.transaction.annotation.enabletransactionmanagement; import org.springframework.transaction.annotation.propagation; import org.springframework.transaction.annotation.transactional; import org.springframework.web.bind.annotati
Read more

go - Golang: panic: runtime error: invalid memory address or nil pointer dereference using bufio.Scanner -

-
i implementing go program uses bufio.scanner , bufio.writer have packaged code follows package main import ( "fmt" "player/command" "strings" ) func main() { //enter code here. read input stdin. print output stdout commands.scanner.scan() { //scan new line , send comand variable check command exist or not input := strings.split(strings.trim(commands.scanner.text(), " "), " ") command := input[0] if command == "" { fmt.printf("$ %s:", commands.pwd) continue } if !commands.commands[command] { commands.throwerror("cannot recognize input.") } else { commands.execute(command, input[1:], nil) } fmt.printf("$ %s:", commands.pwd) } } i using init.go file in main package follows package main import ( "flag" "player/sourc
Read more

c - double free or corruption (fasttop) -

-
this code reads null terminated string file (file containing null terminated strings & should provide index wanted string). error: *** error in `./main': double free or corruption (fasttop): 0x090a4a80 *** aborted code: char *tmp_realloc=null; char *sstring=null; int i=1; /*set file pointer point string*/ fseek(fh,index,seek_set); sstring=(char*)malloc(sizeof(char)); if(sstring == null) return null; tmp_realloc=sstring; while( (*(sstring+i-1)=(char)fgetc((file*)fh)) != 0x0 ) { /*reallocate more memory*/ tmp_realloc=(char*)realloc((char*)sstring,++i); /*if not same address copy old new & set old point new*/ if(tmp_realloc != sstring){ strcpy((char*)tmp_realloc,(char*)sstring); free(sstring); sstring=tmp_realloc; } } could tell me pointer causing issue (& reason) ? remove part /*if not same address copy old new & set old point new*/ if(tmp_realloc != sstring){ strc
Read more