Covar.java

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package org.apache.doris.nereids.trees.expressions.functions.agg;

import org.apache.doris.catalog.FunctionSignature;
import org.apache.doris.nereids.trees.expressions.Expression;
import org.apache.doris.nereids.trees.expressions.functions.ExplicitlyCastableSignature;
import org.apache.doris.nereids.trees.expressions.shape.UnaryExpression;
import org.apache.doris.nereids.trees.expressions.visitor.ExpressionVisitor;
import org.apache.doris.nereids.types.BigIntType;
import org.apache.doris.nereids.types.DoubleType;
import org.apache.doris.nereids.types.FloatType;
import org.apache.doris.nereids.types.IntegerType;
import org.apache.doris.nereids.types.SmallIntType;
import org.apache.doris.nereids.types.TinyIntType;

import com.google.common.base.Preconditions;
import com.google.common.collect.ImmutableList;

import java.util.List;

/**
 * AggregateFunction 'covar'. This class is generated by GenerateFunction.
 */
public class Covar extends NullableAggregateFunction
        implements UnaryExpression, ExplicitlyCastableSignature {

    public static final List<FunctionSignature> SIGNATURES = ImmutableList.of(
            FunctionSignature.ret(DoubleType.INSTANCE).args(DoubleType.INSTANCE, DoubleType.INSTANCE),
            FunctionSignature.ret(DoubleType.INSTANCE).args(BigIntType.INSTANCE, BigIntType.INSTANCE),
            FunctionSignature.ret(DoubleType.INSTANCE).args(IntegerType.INSTANCE, IntegerType.INSTANCE),
            FunctionSignature.ret(DoubleType.INSTANCE).args(SmallIntType.INSTANCE, SmallIntType.INSTANCE),
            FunctionSignature.ret(DoubleType.INSTANCE).args(TinyIntType.INSTANCE, TinyIntType.INSTANCE),
            FunctionSignature.ret(DoubleType.INSTANCE).args(FloatType.INSTANCE, FloatType.INSTANCE)
    );

    /**
     * constructor with 2 argument.
     */
    public Covar(Expression arg1, Expression arg2) {
        this(false, arg1, arg2);
    }

    /**
     * constructor with 3 arguments.
     */
    public Covar(boolean distinct, Expression arg1, Expression arg2) {
        this(distinct, false, arg1, arg2);
    }

    public Covar(boolean distinct, boolean alwaysNullable, Expression arg1, Expression arg2) {
        super("covar", distinct, alwaysNullable, arg1, arg2);
    }

    /**
     * withDistinctAndChildren.
     */
    @Override
    public Covar withDistinctAndChildren(boolean distinct, List<Expression> children) {
        Preconditions.checkArgument(children.size() == 2);
        return new Covar(distinct, alwaysNullable, children.get(0), children.get(1));
    }

    @Override
    public Covar withAlwaysNullable(boolean alwaysNullable) {
        return new Covar(distinct, alwaysNullable, children.get(0), children.get(1));
    }

    @Override
    public <R, C> R accept(ExpressionVisitor<R, C> visitor, C context) {
        return visitor.visitCovar(this, context);
    }

    @Override
    public List<FunctionSignature> getSignatures() {
        return SIGNATURES;
    }
}