calc()
Here’s how to use calc() function.
A . calc()
Description:
Compute an expression with one or more specified records and return a result.
Syntax:
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A.calc(k,x) |
Compute x against the kth member of A |
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A.calc(p,x) |
Compute x against the members of A specified by the integer sequence p |
Note:
The function computes an expression against one or more specified records and return a result.
Parameter:
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A |
A sequence/a record sequence |
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x |
An expression, which is generally a field name or a legal expression composed of field names, and "~" is used to reference the current record. |
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k |
An integer specifying a record |
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p |
An integer sequence specifying multiple records |
Return value:
The result of x or a sequence composed of results of x
Example:
Compute x against the kth member:
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A |
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1 |
=[1,3,6,2,8] |
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2 |
=A1.calc(3,~*2) |
12; compute expression "~*2" against the third member of sequence A1, "~" indicates the current member. The result is 12. |
Compute x against the members of A specified by the integer sequence p:
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A |
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1 |
=[1,3,6,2,8] |
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2 |
=A1.calc([4,3],~*2) |
Compute expression "~*2" against the fourth and the third members of sequence A1 separately and the result is [4,12]. |
Do the computation against a table sequence:
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A |
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1 |
=demo.query("select * from EMPLOYEE") |
Return a table sequence.
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2 |
=A1.calc(2,age(HIREDATE)+5) |
Compute the number of years an employee works in the company according to hire date against the second record. |
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3 |
=A1.calc(A1.pselect@a(DEPT=="Administration"), age(HIREDATE)+5) |
Compute "age(HIREDATE)+5" against all the records whose DEPT is "Administration" and return the result as a sequence. |
