Python error: typeerror: UFUNC Add did not contain a loop with signature matching types dtype ( U32) d

taxi_bbox[id].append(sort_data[i][2]+","+sort_data[i][3]+","+sort_data[i][4]+","+sort_data[i][5])

sort_data[i][2] Type problem , First convert to str And then you can do the stitching .

taxi_bbox[id].append(str(sort_data[i][2])+","+str(sort_data[i][3])+","+str(sort_data[i][4])+","+str(sort_data[i][5]))