don't write block if parameters are zero and block is not learned or if features are all zero
don't write block if parameters are zero and block is not learned or if features are all zero

yxliang/voc-dpm,rbgirshick/voc-dpm,tuanthng/voc-dpm,yxliang/voc-dpm,ericzhouh/voc-dpm,rbgirshick/dp-dpm,orchidproject/voc-dpm,rbgirshick/dp-dpm,bikong2/voc-dpm,jizhihang/voc-dpm,jizhihang/voc-dpm,bikong2/voc-dpm,ericzhouh/voc-dpm,orchidproject/voc-dpm,tuanthng/voc-dpm,CVML/voc-dpm,rbgirshick/voc-dpm,CVML/voc-dpm,rbgirshick/dp-dpm