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eachCount

Platform and version requirements: JVM (1.1), JS (1.1), Native (1.1)
fun <T, K> Grouping<T, K>.eachCount(): Map<K, Int>
For JVM, Native

Groups elements from the Grouping source by key and counts elements in each group.



fun main(args: Array<String>) {
//sampleStart
val words = "one two three four five six seven eight nine ten".split(' ')
val frequenciesByFirstChar = words.groupingBy { it.first() }.eachCount()
println("Counting first letters:")
println(frequenciesByFirstChar) // {o=1, t=3, f=2, s=2, e=1, n=1}

val moreWords = "eleven twelve".split(' ')
val moreFrequencies = moreWords.groupingBy { it.first() }.eachCountTo(frequenciesByFirstChar.toMutableMap())
println(moreFrequencies) // {o=1, t=4, f=2, s=2, e=2, n=1}
//sampleEnd
}

Return a Map associating the key of each group with the count of elements in the group.

For JS

Groups elements from the Grouping source by key and counts elements in each group.

Return a Map associating the key of each group with the count of element in the group.

© 2010–2020 JetBrains s.r.o. and Kotlin Programming Language contributors
Licensed under the Apache License, Version 2.0.
https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.collections/each-count.html