aggregate - Clingo 中的聚合计数

Question

测试数据

addEmployee(EmplID, Name1, Name2, TypeOfWork, Salary, TxnDate)
addEmployee("tjb1998", "eva", "mcdowell", "ra", 55000, 20).
addEmployee("tjb1987x", "ben", "xena", "cdt", 68000, q50).
addEmployee("tjb2112", "ryoko", "hakubi", "ra", 63000, 60).
addEmployee("tjb1987", "ben", "croshaw", "cdt", 68000, 90).
addEmployee("tjb3300m", "amane", "mauna", "ma", 61000, 105).

我想根据工作类型和特定工作类型的员 worker 数对员工进行分组。例如:

ra 4
cdt 2
ma 1

下面是我要运行的查询

employee(TOW) :- addEmployee(_,_,_,TOW,_,_).
nmbrEmployeesOfSameType (N) :- N = #count { employee(TOW) }.

请指教，我是Clingo的初学者

Answer 1

试试这个:

addEmployee("tjb1998", "eva", "mcdowell", "ra", 55000, 20).
addEmployee("tjb1987x", "ben", "xena", "cdt", 68000, q50).
addEmployee("tjb2112", "ryoko", "hakubi", "ra", 63000, 60).
addEmployee("tjb1987", "ben", "croshaw", "cdt", 60000, 90).
addEmployee("tjb3300m", "amane", "mauna", "ma", 61000, 105).


getType(P, X) :- addEmployee(X, _, _, P, _, _).

type(P) :- addEmployee(_, _, _, P, _, _).

result(P, S) :- S = #count{ I : getType(P,I)}, type(P).

#show result/2.

输出将如下所示:

clingo version 4.5.3
Reading from test.lp
Solving...
Answer: 1
result("ra",2) result("cdt",2) result("ma",1)
SATISFIABLE

你也可以复制我的代码运行一下here看看它是否有效。