def _float_from_bool(a):
    """
    Since pytorch only supports matrix multiplication on float,
    IoU computations are done using floating point types.

    This function binarizes the input (positive to True and
    nonpositive to False), and converts from bool to float.
    If the data is already a floating-point type, it leaves
    it keeps the same type; otherwise it uses float.
    """
    if a.dtype == torch.bool:
        return a.float()
    if a.dtype.is_floating_point:
        return a.sign().clamp_(0)
    return (a > 0).float()

    Since pytorch only supports matrix multiplication on float,
    IoU computations are done using floating point types.

    This function binarizes the input (positive to True and
    nonpositive to False), and converts from bool to float.
    If the data is already a floating-point type, it leaves
    it keeps the same type; otherwise it uses float.
    
util/runningstats.py