短语词组短语Piecewise isometry 分片等距asymptotically isometry 渐近等距算子isometry detail 等距Semilinear isometry 半线性保距同构isometry sampling 等距抽样almost isometry 几乎等距isometry transformation 合同変换an isometry 保长对应tangent isometry 切等距 返回 isometry