datetime - R - subsetting by date -

i'm trying subset large dataframe date field ad facing strange behaviour:

1) find interesting time interval:

> ld[ld$bps>30000000,]             date.first.seen duration proto      src.ip.addr src.pt      dst.ip.addr dst.pt tos packets    bytes      bps 1400199 2015-03-31 13:52:24    0.008 tcp      3.3.3.3   3128      4.4.4.4  65115   0      39    32507 32500000 1711899 2015-03-31 14:58:10    0.004 tcp      3.3.3.3   3128      4.4.4.7  49357   0      29    23830 47700000 

2) , try whats happening on second:

> ld[ld$date.first.seen=="2015-03-31 13:52:24",]             date.first.seen duration proto      src.ip.addr src.pt      dst.ip.addr dst.pt tos packets    bytes bps 1401732 2015-03-31 13:52:24   17.436 tcp      3.3.3.3   3128    6.6.6.6  51527   0       3     1608 737 

don't understand behavior - should way more results. example

> ld[1399074,]             date.first.seen duration proto      src.ip.addr src.pt      dst.ip.addr dst.pt tos packets    bytes      bps 1399074 2015-03-31 13:52:24    0.152 tcp      10.10.10.10   3128    11.11.11.11  62375   0       8     3910   205789 

for date use posixlt

> str(ld) 'data.frame':   2657583 obs. of  11 variables:  $ date.first.seen: posixlt, format: "2015-03-31 06:00:00" "2015-03-31 06:00:00" "2015-03-31 06:00:00" "2015-03-31 06:00:01" ... ... 

would appreciate assistance. thanks!

posixlt may carry additional info supressed when printing entire data.frame, timezone, daylight savings etc. have @ https://stat.ethz.ch/r-manual/r-devel/library/base/html/datetimeclasses.html.

printing posixlt variable (ld$date.first.seen) supply @ least of additional information.

if you're not particular reason required keep variable in posixlt , if don't need functionality format enables, simple:

ld$date.first.seen = as.character(ld$date.first.seen) 

added before subset statement solve problem.