Pivot data between long and wide
Fast table pivoting from long to wide and from wide to long.
These functions are supported by dcast.data.table and melt.data.table
from data.table.
longer(.data, ..., name = "name", value = "value", na.rm = FALSE) wider(.data, ..., name, value = NULL, fun = NULL, fill = NA)
.data |
A data.table |
... |
Columns for unchanged group. Flexible, see examples. |
name |
Name for the measured variable names column. |
value |
Name for the data values column(s). |
na.rm |
If |
fun |
Should the data be aggregated before casting?
Defaults to |
fill |
Value with which to fill missing cells. Default uses |
A data.table
stocks <- data.table(
time = as.Date('2009-01-01') + 0:9,
X = rnorm(10, 0, 1),
Y = rnorm(10, 0, 2),
Z = rnorm(10, 0, 4)
)
stocks %>% longer(time)
stocks %>% longer(-(2:4)) # same
stocks %>% longer(-"X|Y|Z") # same
long_stocks = longer(stocks,"ti") # same as above except for assignment
long_stocks %>% wider(time,name = "name",value = "value")
# the unchanged group could be missed if all the rest will be used
long_stocks %>% wider(name = "name",value = "value")Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.