df.filter { index() % 5 == 0 }
Input DataFrame: rowsCount = 7, columnsCount = 5
nameagecityweightisHappy
firstNamelastName
AliceCooper15London54true
BobDylan45Dubai87true
CharlieDaniels20Moscownullfalse
CharlieChaplin40Milannulltrue
BobMarley30Tokyo68true
AliceWolf20null55false
CharlieByrd30Moscow90true

Output DataFrame: rowsCount = 2, columnsCount = 5
nameagecityweightisHappy
firstNamelastName
AliceCooper15London54true
AliceWolf20null55false


df.drop { diffOrNull { age } == 0 }
Input DataFrame: rowsCount = 7, columnsCount = 5
nameagecityweightisHappy
firstNamelastName
AliceCooper15London54true
BobDylan45Dubai87true
CharlieDaniels20Moscownullfalse
CharlieChaplin40Milannulltrue
BobMarley30Tokyo68true
AliceWolf20null55false
CharlieByrd30Moscow90true

Output DataFrame: rowsCount = 7, columnsCount = 5
nameagecityweightisHappy
firstNamelastName
AliceCooper15London54true
BobDylan45Dubai87true
CharlieDaniels20Moscownullfalse
CharlieChaplin40Milannulltrue
BobMarley30Tokyo68true
AliceWolf20null55false
CharlieByrd30Moscow90true


df.update { weight }.where { index() > 4 && city != "Paris" }.with { 50 }
Input DataFrame: rowsCount = 7, columnsCount = 5
nameagecityweightisHappy
firstNamelastName
AliceCooper15London54true
BobDylan45Dubai87true
CharlieDaniels20Moscownullfalse
CharlieChaplin40Milannulltrue
BobMarley30Tokyo68true
AliceWolf20null55false
CharlieByrd30Moscow90true

Step 1: Update
nameagecityweightisHappy
firstNamelastName
AliceCooper15London54true
BobDylan45Dubai87true
CharlieDaniels20Moscownullfalse
CharlieChaplin40Milannulltrue
BobMarley30Tokyo68true
AliceWolf20null55false
CharlieByrd30Moscow90true

DataFrame [7 x 5]

Step 2: Update
nameagecityweightisHappy
firstNamelastName
AliceCooper15London54true
BobDylan45Dubai87true
CharlieDaniels20Moscownullfalse
CharlieChaplin40Milannulltrue
BobMarley30Tokyo68true
AliceWolf20null55false
CharlieByrd30Moscow90true

DataFrame [7 x 5]

Output DataFrame: rowsCount = 7, columnsCount = 5
nameagecityweightisHappy
firstNamelastName
AliceCooper15London54true
BobDylan45Dubai87true
CharlieDaniels20Moscownullfalse
CharlieChaplin40Milannulltrue
BobMarley30Tokyo68true
AliceWolf20null50false
CharlieByrd30Moscow50true