Select/Drop columns

Select/Drop columns by name

R:

mtcars >> select(hp) # select only hp
mtcars >> select(-hp) # drop hp

pandas:

mtcars[['hp', 'name',]] # select only hp and name
mtcars.drop(['hp', 'name'], axis=1) # drop hp

plydata:

mtcars >> dp.select('hp', 'name')
mtcars >> dp.select('hp', 'name', drop=True)
# no list passing

dplython:

dp.DplyFrame(mtcars) >> dp.select(X.hp, X.name)

Neither strings nor lists may be passed to select.

No dropping of columns

dfply:

mtcars >> dp.select('hp', 'name')
mtcars >> dp.select(['hp', 'name'])
mtcars >> dp.select(X.hp, X.name) # either works
mtcars >> dp.select([X.hp, 'name']) even mixing
mtcars >> dp.drop('hp')
mtcars >> dp.drop(X.hp)

dppd:

dp(mtcars).select(['hp', 'name']).pd # must be a list
dp(mtcars).unselect(['hp']).pd # we like symetry
dp(mtcars).drop('hp', axis=1).pd # fallback to pandas method