reorient.py 文件源码

def swap_affine(axes):
    """ Build a correction matrix, from the given orientation of axes to RAS.

    Parameters
    ----------
    axes: str (manadtory)
        the given orientation of the axes.

    Returns
    -------
    rotation: array (4, 4)
        the correction matrix.
    """
    rotation = numpy.eye(4)
    rotation[:3, 0] = CORRECTION_MATRIX_COLUMNS[axes[0]]
    rotation[:3, 1] = CORRECTION_MATRIX_COLUMNS[axes[1]]
    rotation[:3, 2] = CORRECTION_MATRIX_COLUMNS[axes[2]]
    return rotation