/*
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 *  * terms of the Apache License, Version 2.0 which is available at
 *  * https://www.apache.org/licenses/LICENSE-2.0.
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 *  *  See the NOTICE file distributed with this work for additional
 *  *  information regarding copyright ownership.
 *  * Unless required by applicable law or agreed to in writing, software
 *  * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 *  * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 *  * License for the specific language governing permissions and limitations
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package org.eclipse.deeplearning4j.nd4j.evaluation;

import static org.junit.jupiter.api.Assertions.assertEquals;

import org.junit.jupiter.api.Tag;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.params.ParameterizedTest;
import org.junit.jupiter.params.provider.MethodSource;
import org.nd4j.common.tests.tags.NativeTag;
import org.nd4j.common.tests.tags.TagNames;
import org.nd4j.evaluation.custom.CustomEvaluation;
import org.nd4j.linalg.BaseNd4jTestWithBackends;
import org.nd4j.linalg.api.buffer.DataType;
import org.nd4j.linalg.factory.Nd4j;
import org.nd4j.linalg.factory.Nd4jBackend;
import org.nd4j.common.primitives.Pair;

@NativeTag
@Tag(TagNames.SAMEDIFF)
@Tag(TagNames.EVAL_METRICS)
@Tag(TagNames.CUSTOM_FUNCTIONALITY)
public class CustomEvaluationTest extends BaseNd4jTestWithBackends {


    @Override
    public char ordering() {
        return 'c';
    }

    @ParameterizedTest
    @MethodSource("org.nd4j.linalg.BaseNd4jTestWithBackends#configs")
    public void customEvalTest(Nd4jBackend backend){
        CustomEvaluation accuracyEval = new CustomEvaluation<>(
                (labels, pred, mask, meta) -> new Pair<>(labels.eq(pred).castTo(DataType.INT).sumNumber(), labels.size(0)),
                CustomEvaluation.mergeConcatenate());

        accuracyEval.eval(Nd4j.createFromArray(1, 1, 2, 1, 3), Nd4j.createFromArray(1, 1, 4, 1, 2));

        double acc = accuracyEval.getValue(new CustomEvaluation.Metric<Pair<Number, Long>>(
                (list) -> {
                    int sum = 0;
                    int count = 0;
                    for(Pair<Number, Long> p : list){
                        sum += p.getFirst().intValue();
                        count += p.getSecond();
                    }
                    return ((double) (sum)) / count;
                }
        ));

        assertEquals(acc, 3.0/5, 0.001,"Accuracy");

    }

}
