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The module for FunctionalJ Core.

There is a newer version: 1.0.17

// ============================================================================
// Copyright (c) 2017-2021 Nawapunth Manusitthipol (NawaMan - http://nawaman.net).
// ----------------------------------------------------------------------------
// MIT License
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
// ============================================================================
package functionalj.list;

import java.util.ArrayList;
import java.util.List;

import functionalj.list.doublelist.DoubleFuncList;
import lombok.val;


public class FuncListHelper {
    
    static  FuncList> segmentByPercentiles(AsFuncList funcList, DoubleFuncList percentiles) {
        val list = funcList.asFuncList();
        val size = list.size();
        DoubleFuncList indexes = percentiles
                .append(100.0)
                .sorted()
                .map   (d -> (int)Math.round(d*size/100))
                .toImmutableList();
        
        val lists   = new ArrayList>();
        for (int i = 0; i < indexes.size(); i++) {
            lists.add(new ArrayList());
        }
        int idx = 0;
        for (int i = 0; i < size; i++) {
            if (i >= indexes.get(idx)) {
                idx++;
            }
            val l = lists.get(idx);
            val element = list.get(i);
            l.add(element);
        }
        
        return FuncList.from(lists.stream().map(each -> ImmutableFuncList.from(each.stream())));
    }
    
}