Bahasa Q - Fungsi Bawaan
Itu qbahasa pemrograman memiliki serangkaian fungsi bawaan yang kaya dan kuat. Fungsi bawaan dapat dari jenis berikut -
String function - Mengambil string sebagai input dan mengembalikan string.
Aggregate function - Mengambil daftar sebagai input dan mengembalikan atom.
Uniform function - Mengambil daftar dan mengembalikan daftar hitungan yang sama.
Mathematical function - Mengambil argumen numerik dan mengembalikan argumen numerik.
Miscellaneous function - Semua fungsi selain yang disebutkan di atas.
Fungsi String
Seperti - pencocokan pola
q)/like is a dyadic, performs pattern matching, return 1b on success else 0b
q)"John" like "J??n"
1b
q)"John My Name" like "J*"
1bltrim - menghilangkan awalan kosong
q)/ ltrim - monadic ltrim takes string argument, removes leading blanks
q)ltrim " Rick "
"Rick "rtrim - menghapus jejak kosong
q)/rtrim - takes string argument, returns the result of removing trailing blanks
q)rtrim " Rick "
" Rick"ss - pencarian string
q)/ss - string search, perform pattern matching, same as "like" but return the indices of the matches of the pattern in source.
q)"Life is beautiful" ss "i"
1 5 13trim - menghilangkan bagian depan dan belakang yang kosong
q)/trim - takes string argument, returns the result of removing leading & trailing blanks
q)trim " John "
"John"Fungsi Matematika
acos - kebalikan dari cos
q)/acos - inverse of cos, for input between -1 and 1, return float between 0 and pi
q)acos 1
0f
q)acos -1
3.141593
q)acos 0
1.570796cor - memberi korelasi
q)/cor - the dyadic takes two numeric lists of same count, returns a correlation between the items of the two arguments
q)27 18 18 9 0 cor 27 36 45 54 63
-0.9707253silang - produk Cartesian
q)/cross - takes atoms or lists as arguments and returns their Cartesian product
q)9 18 cross `x`y`z
9 `x
9 `y
9 `z
18 `x
18 `y
18 `zvar - varians
q)/var - monadic, takes a scaler or numeric list and returns a float equal to the mathematical variance of the items
q)var 45
0f
q)var 9 18 27 36
101.25wavg
q)/wavg - dyadic, takes two numeric lists of the same count and returns the average of the second argument weighted by the first argument.
q)1 2 3 4 wavg 200 300 400 500
400fFungsi Agregat
semua - & operasi
q)/all - monadic, takes a scaler or list of numeric type and returns the result of & applied across the items.
q)all 0b
0b
q)all 9 18 27 36
1b
q)all 10 20 30
1bApa saja - | operasi
q)/any - monadic, takes scaler or list of numeric type and the return the result of | applied across the items
q)any 20 30 40 50
1b
q)any 20012.02.12 2013.03.11
'20012.02.12prd - produk aritmatika
q)/prd - monadic, takes scaler, list, dictionary or table of numeric type and returns the arithmetic product.
q)prd `x`y`z! 10 20 30
6000
q)prd ((1 2; 3 4);(10 20; 30 40))
10 40
90 160Jumlah - jumlah aritmatika
q)/sum - monadic, takes a scaler, list,dictionary or table of numeric type and returns the arithmetic sum.
q)sum 2 3 4 5 6
20
q)sum (1 2; 4 5)
5 7Fungsi Seragam
Delta - perbedaan dari item sebelumnya.
q)/deltas -takes a scalar, list, dictionary or table and returns the difference of each item from its predecessor.
q)deltas 2 3 5 7 9
2 1 2 2 2
q)deltas `x`y`z!9 18 27
x | 9
y | 9
z | 9mengisi - mengisi nilai nulls
q)/fills - takes scalar, list, dictionary or table of numeric type and returns a c copy of the source in which non-null items are propagated forward to fill nulls
q)fills 1 0N 2 0N 4
1 1 2 2 4
q)fills `a`b`c`d! 10 0N 30 0N
a | 10
b | 10
c | 30
d | 30maks - maksimum kumulatif
q)/maxs - takes scalar, list, dictionary or table and returns the cumulative maximum of the source items.
q)maxs 1 2 4 3 9 13 2
1 2 4 4 9 13 13
q)maxs `a`b`c`d!9 18 0 36
a | 9
b | 18
c | 18
d | 36Fungsi Miscellaneous
Hitung - jumlah kembali elemen
q)/count - returns the number of entities in its argument.
q)count 10 30 30
3
q)count (til 9)
9
q)count ([]a:9 18 27;b:1.1 2.2 3.3)
3Berbeda - mengembalikan entitas yang berbeda
q)/distinct - monadic, returns the distinct entities in its argument
q)distinct 1 2 3 4 2 3 4 5 6 9
1 2 3 4 5 6 9Kecuali - elemen tidak ada di argumen kedua.
q)/except - takes a simple list (target) as its first argument and returns a list containing the items of target that are not in its second argument
q)1 2 3 4 3 1 except 1
2 3 4 3fill - isi null dengan argumen pertama
q)/fill (^) - takes an atom as its first argument and a list(target) as its second argument and return a list obtained by substituting the first argument for every occurrence of null in target
q)42^ 9 18 0N 27 0N 36
9 18 42 27 42 36
q)";"^"Life is Beautiful"
"Life;is;Beautiful"