计数clingo中的聚合

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).

我希望按照工作类型和特定类型工作的员工数量对员工进行分组。例如：

ra 4
cdt 2
ma 1

下面是我试图运行的查询

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.

输出看起来像：

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

您也可以复制我的代码并运行它here以查看它是否有效。