// Get the shape of the gt box (centered at (100, 100))
gt_shape = torch.FloatTensor(np.array([100, 100, gw, gh])).unsqueeze(0)
// Get shape of anchor box
anchor_shapes = torch.ones((len(anchors), 4)).float() * 100
anchor_shapes[:, 2:] = anchors
// Compute iou between gt and anchor shapes
anch_ious = bbox_iou(gt_shape, anchor_shapes, x1y1x2y2=False)
// Where the overlap is larger than threshold set mask to zero (ignore)