Carregar o dataset e filtrar apenas as observacoes da coluna
COMMAND que estao completamente entre colchetes, usando
expressao regular com a funcao grep().
ds <- read.csv(
"https://www.dropbox.com/s/kiut6raev4z1e2u/compdataset_V2.csv?dl=1"
)
cat("Dimensoes do dataset:", nrow(ds), "linhas e", ncol(ds), "colunas\n")## Dimensoes do dataset: 140 linhas e 6 colunashead(ds)## USER PID VSZ RSS X.MEM
## 1 root 397 2896 1912 0.2
## 2 nobody 342 4320 2156 0.2
## 3 root 320 7944 2348 0.2
## 4 root 449 5620 2384 0.2
## 5 pi 557 8576 2648 0.2
## 6 pi 4063 9944 2680 0.2
## COMMAND
## 1 /sbin/dhcpcd-q-b
## 2 /usr/sbin/thd--triggers/etc/triggerhappy/triggers.d/--socket/run/thd.socket--usernobody--deviceglob/dev/input/event*
## 3 /usr/sbin/cron-f
## 4 /bin/login-f
## 5 -bash
## 6 ps-eouser,pid,vsz,rss,%mem,command--sort=%memx <- ds$COMMAND
cat("Total de observacoes em COMMAND:", length(x), "\n\n")## Total de observacoes em COMMAND: 140cat("Primeiras 10 observacoes:\n")## Primeiras 10 observacoes:print(head(x, 10))## [1] "/sbin/dhcpcd-q-b"
## [2] "/usr/sbin/thd--triggers/etc/triggerhappy/triggers.d/--socket/run/thd.socket--usernobody--deviceglob/dev/input/event*"
## [3] "/usr/sbin/cron-f"
## [4] "/bin/login-f"
## [5] "-bash"
## [6] "ps-eouser,pid,vsz,rss,%mem,command--sort=%mem"
## [7] "/lib/systemd/systemd-hostnamed"
## [8] "[kthreadd]"
## [9] "[rcu_gp]"
## [10] "[rcu_par_gp]"A expressao ^\[.*\]$ garante que o texto esteja
completamente entre colchetes:
^ inicio da string — nada antes do colchete\[ colchete de abertura literal.* qualquer conteudo no meio\] colchete de fechamento literal$ fim da string — nada depois do colcheteresultado <- grep(
pattern = "^\\[.*\\]$",
x,
value = TRUE
)
cat("Total de observacoes entre colchetes:", length(resultado), "\n\n")## Total de observacoes entre colchetes: 80print(resultado)## [1] "[kthreadd]"
## [2] "[rcu_gp]"
## [3] "[rcu_par_gp]"
## [4] "[mm_percpu_wq]"
## [5] "[ksoftirqd/2]"
## [6] "[cpuhp/3]"
## [7] "[migration/3]"
## [8] "[ksoftirqd/3]"
## [9] "[kdevtmpfs]"
## [10] "[netns]"
## [11] "[khungtaskd]"
## [12] "[oom_reaper]"
## [13] "[writeback]"
## [14] "[kcompactd0]"
## [15] "[crypto]"
## [16] "[kblockd]"
## [17] "[watchdogd]"
## [18] "[rpciod]"
## [19] "[kworker/u9:0-hci0]"
## [20] "[xprtiod]"
## [21] "[kswapd0]"
## [22] "[nfsiod]"
## [23] "[kthrotld]"
## [24] "[iscsi_eh]"
## [25] "[dwc_otg]"
## [26] "[DWCNotificatio]"
## [27] "[vchiq-slot/0]"
## [28] "[vchiq-recy/0]"
## [29] "[vchiq-sync/0]"
## [30] "[vchiq-keep/0]"
## [31] "[SMIO]"
## [32] "[irq/86-mmc1]"
## [33] "[mmc_complete]"
## [34] "[kworker/2:1H+kblockd]"
## [35] "[kworker/1:1H-kblockd]"
## [36] "[jbd2/mmcblk0p7-]"
## [37] "[ext4-rsv-conver]"
## [38] "[ipv6_addrconf]"
## [39] "[kworker/3:1H-kblockd]"
## [40] "[kworker/0:2H-mmc_complete]"
## [41] "[SMIO]"
## [42] "[mmal-vchiq]"
## [43] "[mmal-vchiq]"
## [44] "[mmal-vchiq]"
## [45] "[cfg80211]"
## [46] "[brcmf_wq/mmc1:0]"
## [47] "[brcmf_wdog/mmc1]"
## [48] "[kworker/0:2-events]"
## [49] "[kworker/u9:1-hci0]"
## [50] "[krfcommd]"
## [51] "[kworker/1:0-mm_percpu_wq]"
## [52] "[kworker/3:2-events]"
## [53] "[kworker/0:0]"
## [54] "[kworker/3:0]"
## [55] "[kworker/1:0H]"
## [56] "[kworker/u8:0-cfg80211]"
## [57] "[kworker/3:0H]"
## [58] "[kworker/2:2-events]"
## [59] "[kworker/1:1-mm_percpu_wq]"
## [60] "[kworker/1:2H]"
## [61] "[kworker/3:2H]"
## [62] "[kworker/2:2H]"
## [63] "[kworker/0:1H]"
## [64] "[kworker/u8:2+flush-179:0]"
## [65] "[kworker/2:0-events]"
## [66] "[kworker/2:1-events]"
## [67] "[kworker/1:2-events_power_efficient]"
## [68] "[kworker/2:0H]"
## [69] "[kworker/0:0H]"
## [70] "[kworker/u8:1]"
## [71] "[ksoftirqd/0]"
## [72] "[rcu_sched]"
## [73] "[rcu_bh]"
## [74] "[migration/0]"
## [75] "[cpuhp/0]"
## [76] "[cpuhp/1]"
## [77] "[migration/1]"
## [78] "[ksoftirqd/1]"
## [79] "[cpuhp/2]"
## [80] "[migration/2]"cat("Exemplos que NAO devem aparecer (texto fora dos colchetes):\n")## Exemplos que NAO devem aparecer (texto fora dos colchetes):nao_colchetes <- grep(
pattern = "^\\[.*\\]$",
x,
value = TRUE,
invert = TRUE
)
print(head(nao_colchetes, 5))## [1] "/sbin/dhcpcd-q-b"
## [2] "/usr/sbin/thd--triggers/etc/triggerhappy/triggers.d/--socket/run/thd.socket--usernobody--deviceglob/dev/input/event*"
## [3] "/usr/sbin/cron-f"
## [4] "/bin/login-f"
## [5] "-bash"