#!/usr/bin/env python # -*- coding: utf-8 -*- # Copyright 1999-2020 Alibaba Group Holding Ltd. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. import numpy as np from ...core import ExecutableTuple from ..datasource import tensor as astensor [docs]def atleast_2d(*tensors): """ View inputs as tensors with at least two dimensions. Parameters ---------- tensors1, tensors2, ... : array_like One or more array-like sequences. Non-tensor inputs are converted to tensors. Tensors that already have two or more dimensions are preserved. Returns ------- res, res2, ... : Tensor A tensor, or list of tensors, each with ``a.ndim >= 2``. Copies are avoided where possible, and views with two or more dimensions are returned. See Also -------- atleast_1d, atleast_3d Examples -------- >>> import mars.tensor as mt >>> mt.atleast_2d(3.0).execute() array([[ 3.]]) >>> x = mt.arange(3.0) >>> mt.atleast_2d(x).execute() array([[ 0., 1., 2.]]) >>> mt.atleast_2d(1, [1, 2], [[1, 2]]).execute() [array([[1]]), array([[1, 2]]), array([[1, 2]])] """ new_tensors = [] for x in tensors: x = astensor(x) if x.ndim == 0: x = x[np.newaxis, np.newaxis] elif x.ndim == 1: x = x[np.newaxis, :] new_tensors.append(x) if len(new_tensors) == 1: return new_tensors[0] return ExecutableTuple(new_tensors)