org.nd4j.evaluation.curves.RocCurve Maven / Gradle / Ivy
/*
* ******************************************************************************
* *
* *
* * This program and the accompanying materials are made available under the
* * terms of the Apache License, Version 2.0 which is available at
* * https://www.apache.org/licenses/LICENSE-2.0.
* *
* * 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
* * under the License.
* *
* * SPDX-License-Identifier: Apache-2.0
* *****************************************************************************
*/
package org.nd4j.evaluation.curves;
import lombok.Data;
import lombok.EqualsAndHashCode;
import org.nd4j.common.base.Preconditions;
import org.nd4j.shade.jackson.annotation.JsonProperty;
@Data
@EqualsAndHashCode(exclude = {"auc"}, callSuper = false)
public class RocCurve extends BaseCurve {
private double[] threshold;
private double[] fpr;
private double[] tpr;
private Double auc;
public RocCurve(@JsonProperty("threshold") double[] threshold, @JsonProperty("fpr") double[] fpr,
@JsonProperty("tpr") double[] tpr) {
this.threshold = threshold;
this.fpr = fpr;
this.tpr = tpr;
}
@Override
public int numPoints() {
return threshold.length;
}
@Override
public double[] getX() {
return fpr;
}
@Override
public double[] getY() {
return tpr;
}
@Override
public String getTitle() {
return "ROC (Area=" + format(calculateAUC(), DEFAULT_FORMAT_PREC) + ")";
}
/**
* @param i Point number, 0 to numPoints()-1 inclusive
* @return Threshold of a given point
*/
public double getThreshold(int i) {
Preconditions.checkArgument(i >= 0 && i < threshold.length, "Invalid index: " + i);
return threshold[i];
}
/**
* @param i Point number, 0 to numPoints()-1 inclusive
* @return True positive rate of a given point
*/
public double getTruePositiveRate(int i) {
Preconditions.checkArgument(i >= 0 && i < tpr.length, "Invalid index: " + i);
return tpr[i];
}
/**
* @param i Point number, 0 to numPoints()-1 inclusive
* @return False positive rate of a given point
*/
public double getFalsePositiveRate(int i) {
Preconditions.checkArgument(i >= 0 && i < fpr.length, "Invalid index: " + i);
return fpr[i];
}
/**
* Calculate and return the area under ROC curve
*/
public double calculateAUC() {
if (auc != null) {
return auc;
}
auc = calculateArea();
return auc;
}
public static RocCurve fromJson(String json) {
return fromJson(json, RocCurve.class);
}
public static RocCurve fromYaml(String yaml) {
return fromYaml(yaml, RocCurve.class);
}
}