1 | #include <Functions/IFunctionImpl.h> |
---|---|
2 | #include <Functions/FunctionFactory.h> |
3 | #include <Functions/FunctionHelpers.h> |
4 | #include <DataTypes/DataTypeAggregateFunction.h> |
5 | #include <DataTypes/DataTypesNumber.h> |
6 | #include <Columns/ColumnAggregateFunction.h> |
7 | #include <Common/typeid_cast.h> |
8 | |
9 | #include <Columns/ColumnVector.h> |
10 | #include <Columns/ColumnsNumber.h> |
11 | #include <iostream> |
12 | |
13 | #include <Common/PODArray.h> |
14 | #include <Columns/ColumnArray.h> |
15 | |
16 | namespace DB |
17 | { |
18 | |
19 | namespace ErrorCodes |
20 | { |
21 | extern const int ILLEGAL_COLUMN; |
22 | extern const int ILLEGAL_TYPE_OF_ARGUMENT; |
23 | } |
24 | |
25 | |
26 | /** finalizeAggregation(agg_state) - get the result from the aggregation state. |
27 | * Takes state of aggregate function. Returns result of aggregation (finalized state). |
28 | */ |
29 | class FunctionEvalMLMethod : public IFunction |
30 | { |
31 | public: |
32 | static constexpr auto name = "evalMLMethod"; |
33 | static FunctionPtr create(const Context & context) |
34 | { |
35 | return std::make_shared<FunctionEvalMLMethod>(context); |
36 | } |
37 | FunctionEvalMLMethod(const Context & context_) : context(context_) |
38 | {} |
39 | |
40 | String getName() const override |
41 | { |
42 | return name; |
43 | } |
44 | |
45 | bool isVariadic() const override |
46 | { |
47 | return true; |
48 | } |
49 | size_t getNumberOfArguments() const override |
50 | { |
51 | return 0; |
52 | } |
53 | |
54 | DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override |
55 | { |
56 | if (arguments.empty()) |
57 | throw Exception("Function "+ getName() + " requires at least one argument", ErrorCodes::BAD_ARGUMENTS); |
58 | |
59 | const auto * type = checkAndGetDataType<DataTypeAggregateFunction>(arguments[0].get()); |
60 | if (!type) |
61 | throw Exception("Argument for function "+ getName() + " must have type AggregateFunction - state of aggregate function.", |
62 | ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT); |
63 | |
64 | return type->getReturnTypeToPredict(); |
65 | } |
66 | |
67 | void executeImpl(Block & block, const ColumnNumbers & arguments, size_t result, size_t /*input_rows_count*/) override |
68 | { |
69 | if (arguments.empty()) |
70 | throw Exception("Function "+ getName() + " requires at least one argument", ErrorCodes::BAD_ARGUMENTS); |
71 | |
72 | const auto * model = block.getByPosition(arguments[0]).column.get(); |
73 | |
74 | if (const auto * column_with_states = typeid_cast<const ColumnConst *>(model)) |
75 | model = column_with_states->getDataColumnPtr().get(); |
76 | |
77 | const auto * agg_function = typeid_cast<const ColumnAggregateFunction *>(model); |
78 | |
79 | if (!agg_function) |
80 | throw Exception("Illegal column "+ block.getByPosition(arguments[0]).column->getName() |
81 | + " of first argument of function "+ getName(), ErrorCodes::ILLEGAL_COLUMN); |
82 | |
83 | block.getByPosition(result).column = agg_function->predictValues(block, arguments, context); |
84 | } |
85 | |
86 | const Context & context; |
87 | }; |
88 | |
89 | void registerFunctionEvalMLMethod(FunctionFactory & factory) |
90 | { |
91 | factory.registerFunction<FunctionEvalMLMethod>(); |
92 | } |
93 | |
94 | } |
95 |