stimulus_size_as_visual_angles.py

def stimulus_size_as_visual_angles(stim_size, screen_size, screen_angles):
    """Convert stimulus size (in pixels) to visual viewing angle (in degree).

    Parameters
    ----------
    stim_size : (int, int)
        the size of the stimulus in pixels (width, height)
    screen_dims : (int, int)
        the pixel dimensions of the screen (width, height)
    screen_angles : (float, float)
        the visual viewing angles of the screen (width, height)

    Returns
    -------
    angles : (float, float)
        the visual viewing angle of the distance (width, height)

    """
    
    return ((stim_size[0] / screen_size[0] * 100) / 100 * screen_angles[0],
            (stim_size[1] / screen_size[1] * 100) / 100 * screen_angles[1])