Shifting a BitArray

Question

I\'m currently trying to shift a BitArray while keeping its length. Since there\'s no built-in method I\'m struggling to build one but can\'t make it work, unfortunatly.

Answer 1

Still not 100% sure what's the issue. Here's a naive implementation:

void Main()
{
    // Creates and initializes a BitArrays of size 7 (you have 421).
    bool[] myBools = new bool[7] { true,false,false,true,true,false,true };
    BitArray myBA1 = new BitArray(myBools );

    PrintBitArray(myBA1);              // 1001101
    PrintBitArray(ShiftRight(myBA1));  // 0100110
    PrintBitArray(ShiftLeft (myBA1));  // 0011010
}

BitArray ShiftRight(BitArray aSource) {
    bool[] new_arr  = new bool[( aSource.Count)];
    for (int i = 0; i < aSource.Count -1; i++)
        new_arr[i+1] = aSource[i];

    return new BitArray(new_arr);
}   

BitArray ShiftLeft(BitArray aSource) {
    bool[] new_arr  = new bool[( aSource.Count)];
    for (int i = 0; i < aSource.Count -1; i++)
        new_arr[i] = aSource[i+1];

    return new BitArray(new_arr);
}

string PrintBitArray(BitArray aSource) {
    StringBuilder sb  = new StringBuilder();
    foreach (var bit in aSource)
    {
        sb.Append( (bool)bit ? 1 : 0 );
    }
    return sb.ToString();
}

Note how bits are copied in the loops, and that the third PrintBitArray is done on the original input, not on the outcome of the second.

Answer 2

public static bool[] Left_shiftBitArray(bool[] Array, int count)
        {
            Array = BitArray_LRotat(Array, count);
            for (int i=Array.GetLength(0)-1; i>=(Array.GetLength(0)-count); i--)
            {
                Array[i] = false;
            }

            return Array;
        }

        public static bool[] BitArray_LRotat(bool[] input, int x)
        {
            //bool [] temp= new bool[input.Length];
            bool[] final = new bool[input.Length];
            for (int i = input.Length; i > x; i--)
            {
                final[i - x - 1] = input[i - 1];
            }
            for (int i = x; i > 0; i--)
            {
                final[(input.Length) - i] = input[x - i];
            }
            return final;
        }