Create Ranges in the list

Question

I have a Price list as

I want to add prices in 10 increments below 100. Above 100 to display in increments of 100

So my final price list would be like

Has anyone has done something similar to this. Any help or suggestions would be appreciated.

Thanks in advance

What do you intend to do with `21` and `150` from the original list? Just throw them away? — maccettura, Nov 08 '19 at 02:23

Anu Viswan · Answer 1 · 2019-11-08T03:49:20.573

There is a bit of lack of clarity on whether you want to generate 'n' elements or whether you want to generate till the max value in the list.

Case 1 : If Generate till Max Value in List

public IEnumerable<int> Generate(int maxValue)
{
    var currentValue = 0;
    while(currentValue<maxValue)
    {
        currentValue += currentValue < 100 ? 10:100;
        yield return currentValue;
    }
}

You can now use the method as

var myList = new List<int>(new int[] { 12, 21, 30, 90, 100, 150, 404 });
var result = Generate(myList.Max());

Case 2 : When you want to generate N Elements.

var initialValue = 0;
var list = Enumerable.Range(1,totalNumberOfExpectedItems)
                     .Select(x=> 
                       { 
                          initialValue = initialValue < 100 ? initialValue + 10 : initialValue + 100; 
                          return initialValue;
                       })

Enumerable.Range aids in generating sequence in a specified range

For totalNumberOfExpectedItems = 13,

Output

score 0 · Answer 2 · answered Nov 08 '19 at 02:16

I believe that the following program works as you desire:

using System;
using System.Linq;

namespace csharp
{
    class Program
    {
        static void Main(string[] args)
        {
            var prices = new int[]{10, 21, 30, 90, 100, 150, 400}.ToList();
            var finalPriceList =
                Enumerable
                .Range(0, 10)
                .Select(i => prices.Min() + 10 * i)
                .TakeWhile(i => i < Math.Min(100, prices.Max()))
                .Concat(
                    Enumerable
                    .Range(1, 1000)
                    .Select(i => 100 * i)
                    .TakeWhile(i => i <= prices.Max())
                ).ToList();
            Console.WriteLine(string.Join(", ", finalPriceList));
        }
    }
}

It prints:

10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 200, 300, 400

preciousbetine · Answer 3 · 2019-11-08T06:58:10.817

Try this...

I am assuming you are getting all values between the lowest and highest values in the list.

List<int> myList = new List<int>(new int[] { 12, 21, 30, 90, 100, 150, 404 });
int max = myList.Max() - myList.Max() % 100;
int min = myList.Min() - myList.Min() % 10;

int tmp = (int)Math.Round(Math.Log10(min), MidpointRounding.ToZero);
List<int> newList = new List<int>();
for (int a = tmp, b = min / (int)Math.Pow(10, tmp); (Math.Pow(10, a) * b <= max); )
{
     newList.Add((int)(Math.Pow(10, a) * b));
     if (b < 9) b++;
     else
     {
         b = 1;
         a++;
     }
}

//newList : [10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 200, 300, 400]

Create Ranges in the list

3 Answers3