move to left if number is lees than 5

library(data.table)
library(dplyr)
library(magrittr)
dt = fread('No, A, B, C, D, E, F, G
1, 8, 9, 0, 5, 7, 1, 1
2, 4, 0, 6, 1, 7, 0, 3
3, 0, 1, 0, 6, 0, 0, 0
4, 5, 3, 2, 7, 0, 2, 0
5, 5, 6, 2, 0, 3, 1, 0
6, 0, 3, 2, 1, 6, 7, 1
')
f = function(x){ x[x<5] = 0; x}
dt %<>% mutate_each(funs(f), -No)
dt
#    No  A  B  C  D  E  F  G
# 1:  1  8  9  0  5  7  0  0
# 2:  2  0  0  6  0  7  0  0
# 3:  3  0  0  0  6  0  0  0
# 4:  4  5  0  0  7  0  0  0
# 5:  5  5  6  0  0  0  0  0
# 6:  6  0  0  0  0  6  7  0
## 就回到原本的案例了