Function vlfeat_sys::vl_imgradient_polar_d

pub unsafe extern "C" fn vl_imgradient_polar_d(
    amplitudeGradient: *mut f64, 
    angleGradient: *mut f64, 
    gradWidthStride: vl_size, 
    gradHeightStride: vl_size, 
    image: *const f64, 
    imageWidth: vl_size, 
    imageHeight: vl_size, 
    imageStride: vl_size
)