How to write a 2D array of floats in a file as bytes?

I have the following float array:

float[] arr = [ (1.2,2.3,2.4), (4.7,4.8,9.8) ]

and I wish to write it on a file through DataOutputStream in bytes. I have tried this so far:

      DataOutputStream out = new DataOutputStream(new FileOutputStream(filename));

      for(int row = 0; row<arr.length; row ++) {
                for(int column = 0; column<arr[0].length; column++) {
                    out.writeByte(arr[row][column]);
                }
            }

But I am getting this error:

The method writeByte(int) in the type DataOutputStream is not applicable for the arguments (float)

Normally, the same thing would work if arr and integer array was. Does somebody know how I could write each element of the array as byte in the file? Thanks in advance

This code snippet is working:

// fix array declaration
float[][] arr = { {1.2f,2.3f,2.4f}, {4.7f,4.8f,9.8f} };

// use try-with-resources to close output stream automatically
try (DataOutputStream out = new DataOutputStream(new FileOutputStream("floats.dat"))) {
    for (int row = 0; row < arr.length; row++) {
        for (int column = 0; column < arr[row].length; column++) {
            out.writeFloat(arr[row][column]);
        }
    }
}
// resulting file has length 24 bytes

try (DataOutputStream out = new DataOutputStream(new FileOutputStream("float_bytes.dat"))) {
    for (int row = 0; row < arr.length; row++) {
        for (int column = 0; column < arr[row].length; column++) {
            out.writeByte((byte)arr[row][column]);
        }
    }
}
// resulting file has length 6 bytes