用了一份很大的数据集,进行条件筛选:
t0 = Sys.time()
cprv_GM[cprv_GM$is_turbo == '非增压',]
Sys.time() - t0 # Time difference of 34.91563 secs
t0 = Sys.time()
filter(cprv_GM, is_turbo == '非增压')
Sys.time() - t0 # Time difference of 35.17037 secs
t0 = Sys.time()
subset(cprv_GM, is_turbo == '非增压')
Sys.time() - t0 # Time difference of 34.67368 secs
结语:
其实三种方法差距并不大,但还建议优先选择subset的方法。
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