measure/src/main/scala/org/apache/griffin/measure/context/streaming/metric/AccuracyMetric.scala

/*
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regarding copyright ownership.  The ASF licenses this file
to you under the Apache License, Version 2.0 (the
"License"); you may not use this file except in compliance
with the License.  You may obtain a copy of the License at

  http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing,
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"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.
*/
package org.apache.griffin.measure.context.streaming.metric

/**
  * accuracy metric
  * @param miss     miss count
  * @param total    total count
  */
case class AccuracyMetric(miss: Long, total: Long) extends Metric {

  type T = AccuracyMetric

  override def isLegal(): Boolean = getTotal > 0

  def update(delta: T): T = {
    if (delta.miss < miss) AccuracyMetric(delta.miss, total) else this
  }

  def initial(): Boolean = {
    getMatch <= 0
  }

  def eventual(): Boolean = {
    this.miss <= 0
  }

  def differsFrom(other: T): Boolean = {
    (this.miss != other.miss) || (this.total != other.total)
  }

  def getMiss: Long = miss

  def getTotal: Long = total

  def getMatch: Long = total - miss

  def matchPercentage: Double = if (getTotal <= 0) 0 else getMatch.toDouble / getTotal * 100

}