Number of items

count x     count[x]

Where x is

• a list, returns the number of its items
• a dictionary, the number of items in its value
• anything else, 1

q)count 0                            / atom
1
q)count "zero"                       / vector
4
q)count (2;3 5;"eight")              / mixed list
3
q)count each (2;3 5;"eight")
1 2 5
q)count `a`b`c!2 3 5                 / dictionary
3
q)/ the items of a table are its rows
q)count ([]city:`London`Paris`Berlin; country:`England`France`Germany)
3
q)count each ([]city:`London`Paris`Berlin; country:`England`France`Germany)
2 2 2

q)count ({x+y})
1
q)count (+/)
1