conditionalFilter

Syntax

conditionalFilter(X, condition, filterMap)

Arguments

X is a scalar/vector.

condition is a scalar or a vector of the same length as X.

filterMap is a dictionary indicating the filtering conditions

Details

Return true if both of the following conditions are satisfied, otherwise return false.

  • An element in the vector condition is a key to the dictionary filterMap

  • The corresponding element in X is one of the elements of the key’s value in the dictionary filterMap

If both X and condition are vectors, the result is a vector of the same length as X.

Examples

Example 1:

$ conditionalFilter(1 2 3,`a`b`c, dict(`a`b,1 2));
[1,1,0]

$ conditionalFilter(1 2 3,`a`b`b, dict(`a`b,[1 2,3 4]))
[1,0,1]

Example 2:

Get the specified stocks in the specified dates from table t:

2012.06.01: C, MS 2012.06.02: IBM, MS 2012.06.03: MS 2012.06.04: IBM

$ sym = `C`MS`MS`MS`IBM`IBM`C`C`C$SYMBOL
$ date = 2012.06.01 2012.06.01 2012.06.02 2012.06.03 2012.06.01 2012.06.02 2012.06.02 2012.06.03 2012.06.04
$ price = 49.6 29.46 29.52 30.02 174.97 175.23 50.76 50.32 51.29
$ qty = 2200 1900 2100 3200 6800 5400 1300 2500 8800
$ t = table(sym, date, price, qty)
$ t;

sym

date

price

qty

C

2012.06.01

49.60

2200

MS

2012.06.01

29.46

1900

MS

2012.06.02

29.52

2100

MS

2012.06.03

30.02

3200

IBM

2012.06.01

174.97

6800

IBM

2012.06.02

175.23

5400

C

2012.06.02

50.76

1300

C

2012.06.03

50.32

2500

C

2012.06.04

51.29

8800

$ filter = dict(2012.06.01..2012.06.04, [`C`MS, `IBM`MS, `MS, `IBM])
$ select * from t where conditionalFilter(sym, date, filter) order by date, sym;

sym

date

price

qty

C

2012.06.01

49.6

2200

MS

2012.06.01

29.46

1900

IBM

2012.06.02

175.23

5400

MS

2012.06.02

29.52

2100

MS

2012.06.03

30.02

3200

Example 3:

The values of filterMap can also be pairs:

$ t=table(`aaa`aaa`bbb`bbb as id, 2020.09.03 2020.09.10 2020.09.06 2020.09.09 as date)
$ t

id

date

aaa

2020.09.03

aaa

2020.09.10

bbb

2020.09.06

bbb

2020.09.09

$ mydict = dict(`aaa`bbb, [2020.09.01 : 2020.09.09,  2020.09.05 : 2020.09.09])
$ select * from t where conditionalFilter(date, id, mydict);

id

date

aaa

2020.09.03

bbb

2020.09.06

bbb

2020.09.09