[Numpy] Implement atleast_1d/2d/3d

python/mxnet/_numpy_op_doc.py

@@ -408,6 +408,113 @@ def _np_copy(a, out=None):
     pass
 
 
+def _np_atleast_1d(*arys):
+    """
+    Convert inputs to arrays with at least one dimension.
+
+    Scalar inputs are converted to 1-dimensional arrays, whilst higher-dimensional inputs are preserved.
+
+    Parameters
+    ----------
+    arys1, arys2, ... : ndarray
+        One or more input arrays.
+
+    Returns
+    -------
+    ret : ndarray
+        An array, or list of arrays, each with a.ndim >= 1. Copies are made only if necessary.
+
+    See also
+    --------
+    atleast_2d, atleast_3d
+
+    Examples
+    --------
+    >>> np.atleast_1d(1.0)
+    array([1.])
+    >>> x = np.arange(9.0).reshape(3,3)
+    >>> np.atleast_1d(x)
+    array([[0., 1., 2.],
+           [3., 4., 5.],
+           [6., 7., 8.]])
+    >>> np.atleast_1d(np.array(1), np.array([3, 4]))
+    [array([1.]), array([3., 4.])]
+    """
+    pass
+
+
+def _np_atleast_2d(*arys):
+    """
+    Convert inputs to arrays with at least two dimensions.
+
+    Parameters
+    ----------
+    arys1, arys2, ... : ndarray
+        One or more input arrays.
+
+    Returns
+    -------
+    ret : ndarray
+        An array, or list of arrays, each with a.ndim >= 2. Copies are made only if necessary.
+
+    See also
+    --------
+    atleast_1d, atleast_3d
+
+    Examples
+    --------
+    >>> np.atleast_2d(3.0)
+    array([[3.]])
+    >>> x = np.arange(3.0)
+    >>> np.atleast_2d(x)
+    array([[0., 1., 2.]])
+    >>> np.atleast_2d(np.array(1), np.array([1, 2]), np.array([[1, 2]]))
+    [array([[1.]]), array([[1., 2.]]), array([[1., 2.]])]
+    """
+    pass
+
+def _np_atleast_3d(*arys):
+    """
+    Convert inputs to arrays with at least three dimension.
+
+    Parameters
+    ----------
+    arys1, arys2, ... : ndarray
+        One or more input arrays.
+
+    Returns
+    -------
+    ret : ndarray
+        An array, or list of arrays, each with a.ndim >= 3.
+        For example, a 1-D array of shape (N,) becomes a view of shape (1, N, 1),
+        and a 2-D array of shape (M, N) becomes a view of shape (M, N, 1).
+
+    See also
+    --------
+    atleast_1d, atleast_2d
+
+    Examples
+    --------
+    >>> np.atleast_3d(3.0)
+    array([[[3.]]])
+    >>> x = np.arange(3.0)
+    >>> np.atleast_3d(x).shape
+    (1, 3, 1)
+    >>> x = np.arange(12.0).reshape(4,3)
+    >>> np.atleast_3d(x).shape
+    (4, 3, 1)
+    >>> for arr in np.atleast_3d(np.array([1, 2]), np.array([[1, 2]]), np.array([[[1, 2]]])):
+    ...     print(arr, arr.shape)
+    ...
+    [[[1.]
+      [2.]]] (1, 2, 1)
+    [[[1.]
+      [2.]]] (1, 2, 1)
+    [[[1. 2.]]] (1, 1, 2)
+    """
+    pass
+
+
 def _np_reshape(a, newshape, order='C', out=None):
     """
     Gives a new shape to an array without changing its data.

python/mxnet/numpy_dispatch_protocol.py

@@ -107,6 +107,9 @@ def _run_with_array_ufunc_proto(*args, **kwargs):
     'min',
     'nonzero',
     'ones_like',
+    'atleast_1d',
+    'atleast_2d',
+    'atleast_3d',
     'prod',
     'ravel',
     'repeat',

src/operator/numpy/np_init_op.cc

@@ -35,6 +35,7 @@ DMLC_REGISTER_PARAMETER(NumpyEyeParam);
 DMLC_REGISTER_PARAMETER(IndicesOpParam);
 DMLC_REGISTER_PARAMETER(LogspaceParam);
 DMLC_REGISTER_PARAMETER(FullLikeOpParam);
+DMLC_REGISTER_PARAMETER(AtleastNDParam);
 
 inline bool NumpyIndicesShape(const nnvm::NodeAttrs& attrs,
                               mxnet::ShapeVector* in_shapes,
@@ -98,6 +99,76 @@ NNVM_REGISTER_OP(_npi_identity)
 .set_attr<FCompute>("FCompute<cpu>", IdentityCompute<cpu>)
 .add_arguments(InitOpParam::__FIELDS__());
 
+template<int NDim>
+inline bool AtleastNDShape(const nnvm::NodeAttrs& attrs,
+                           std::vector<mxnet::TShape> *in_attrs,
+                           std::vector<mxnet::TShape> *out_attrs) {
+  auto &param = nnvm::get<AtleastNDParam>(attrs.parsed);
+
+  CHECK_EQ(in_attrs->size(), param.num_args);
+  CHECK_EQ(out_attrs->size(), param.num_args);
+
+  for (int i = 0; i < param.num_args; ++i) {
+    auto &shape = in_attrs->at(i);
+    if (shape.ndim() < NDim) {
+      mxnet::TShape new_shape(NDim, 1);
+      if (NDim == 2) {
+        if (shape.ndim() == 1) {
+          new_shape[1] = shape[0];
+        }
+      } else if (NDim == 3) {
+        if (shape.ndim() == 1) {
+          new_shape[1] = shape[0];
+        } else if (shape.ndim() == 2) {
+          new_shape[0] = shape[0];
+          new_shape[1] = shape[1];
+        }
+      }
+      SHAPE_ASSIGN_CHECK(*out_attrs, i, new_shape);
+    } else {
+      SHAPE_ASSIGN_CHECK(*out_attrs, i, shape);
+    }
+  }
+
+  return shape_is_known(*in_attrs) && shape_is_known(*out_attrs);
+}
+
+#define NNVM_REGISTER_ATLEAST_ND(N)                                       \
+NNVM_REGISTER_OP(_np_atleast_##N##d)                                      \
+.set_attr_parser(ParamParser<AtleastNDParam>)                             \
+.set_num_inputs(                                                          \
+[](const NodeAttrs& attrs) {                                              \
+  auto &param = nnvm::get<AtleastNDParam>(attrs.parsed);                  \
+  return param.num_args;                                                  \
+})                                                                        \
+.set_num_outputs(                                                         \
+[](const NodeAttrs& attrs) {                                              \
+  auto &param = nnvm::get<AtleastNDParam>(attrs.parsed);                  \
+  return param.num_args;                                                  \
+})                                                                        \
+.set_attr<std::string>("key_var_num_args", "num_args")                    \
+.set_attr<nnvm::FListInputNames>("FListInputNames",                       \
+[](const nnvm::NodeAttrs& attrs) {                                        \
+  int num_args = nnvm::get<AtleastNDParam>(attrs.parsed).num_args;        \
+  std::vector<std::string> ret;                                           \
+  for (int i = 0; i < num_args; i++) {                                    \
+    ret.push_back(std::string("ary") + std::to_string(i));                \
+  }                                                                       \
+  return ret;                                                             \
+})                                                                        \
+.set_attr<nnvm::FInferType>("FInferType", ElemwiseType<-1, -1>)           \
+.set_attr<mxnet::FInferShape>("FInferShape", AtleastNDShape<N>)           \
+.set_attr<nnvm::FGradient>("FGradient", MakeZeroGradNodes)                \
+.set_attr<FCompute>("FCompute<cpu>", AtleastNDCompute<cpu>)               \
+.add_argument("arys", "NDArray-or-Symbol[]", "List of input arrays")      \
+.add_arguments(AtleastNDParam::__FIELDS__())                              \
+
+NNVM_REGISTER_ATLEAST_ND(1);
+
+NNVM_REGISTER_ATLEAST_ND(2);
+
+NNVM_REGISTER_ATLEAST_ND(3);
+
 NNVM_REGISTER_OP(_npi_full_like)
 .set_num_inputs(1)
 .set_num_outputs(1)

src/operator/numpy/np_init_op.cu

@@ -41,6 +41,15 @@ NNVM_REGISTER_OP(_npi_identity)
 NNVM_REGISTER_OP(_npi_full_like)
 .set_attr<FCompute>("FCompute<gpu>", FullLikeOpCompute<gpu>);
 
+NNVM_REGISTER_OP(_np_atleast_1d)
+.set_attr<FCompute>("FCompute<gpu>", AtleastNDCompute<gpu>);
+
+NNVM_REGISTER_OP(_np_atleast_2d)
+.set_attr<FCompute>("FCompute<gpu>", AtleastNDCompute<gpu>);
+
+NNVM_REGISTER_OP(_np_atleast_3d)
+.set_attr<FCompute>("FCompute<gpu>", AtleastNDCompute<gpu>);
+
 NNVM_REGISTER_OP(_npi_arange)
 .set_attr<FCompute>("FCompute<gpu>", RangeCompute<gpu, RangeParam>);
 

src/operator/numpy/np_init_op.h

@@ -272,6 +272,29 @@ void LogspaceCompute(const nnvm::NodeAttrs& attrs,
   });
 }
 
+struct AtleastNDParam : dmlc::Parameter<AtleastNDParam> {
+  int num_args;
+  DMLC_DECLARE_PARAMETER(AtleastNDParam) {
+    DMLC_DECLARE_FIELD(num_args)
+    .set_lower_bound(1)
+    .describe("Number of input arrays.");
+  }
+};
+
+template<typename xpu>
+void AtleastNDCompute(const nnvm::NodeAttrs& attrs,
+                      const OpContext& ctx,
+                      const std::vector<TBlob>& inputs,
+                      const std::vector<OpReqType>& req,
+                      const std::vector<TBlob>& outputs) {
+  auto &param = nnvm::get<AtleastNDParam>(attrs.parsed);
+  CHECK_EQ(inputs.size(), param.num_args);
+  CHECK_EQ(outputs.size(), param.num_args);
+  for (int i = 0; i < param.num_args; ++i) {
+    UnaryOp::IdentityCompute<xpu>(attrs, ctx, {inputs[i]}, {req[i]}, {outputs[i]});
+  }
+}
+
 }  // namespace op
 }  // namespace mxnet
 

tests/python/unittest/test_numpy_interoperability.py

@@ -700,6 +700,30 @@ def _add_workload_ones_like(array_pool):
     OpArgMngr.add_workload('ones_like', array_pool['4x1'])
 
 
+def _add_workload_atleast_nd():
+    a_0 = np.array(1)
+    b_0 = np.array(2)
+    a_1 = np.array([1, 2])
+    b_1 = np.array([2, 3])
+    a_2 = np.array([[1, 2], [1, 2]])
+    b_2 = np.array([[2, 3], [2, 3]])
+    a_3 = [a_2, a_2]
+    b_3 = [b_2, b_2]
+
+    OpArgMngr.add_workload('atleast_1d', a_0, b_0)
+    OpArgMngr.add_workload('atleast_1d', a_1, b_1)
+    OpArgMngr.add_workload('atleast_1d', a_2, b_2)
+    OpArgMngr.add_workload('atleast_1d', a_3, b_3)
+    OpArgMngr.add_workload('atleast_2d', a_0, b_0)
+    OpArgMngr.add_workload('atleast_2d', a_1, b_1)
+    OpArgMngr.add_workload('atleast_2d', a_2, b_2)
+    OpArgMngr.add_workload('atleast_2d', a_3, b_3)
+    OpArgMngr.add_workload('atleast_3d', a_0, b_0)
+    OpArgMngr.add_workload('atleast_3d', a_1, b_1)
+    OpArgMngr.add_workload('atleast_3d', a_2, b_2)
+    OpArgMngr.add_workload('atleast_3d', a_3, b_3)
+
+
 def _add_workload_prod(array_pool):
     OpArgMngr.add_workload('prod', array_pool['4x1'])
 
@@ -1429,6 +1453,7 @@ def _prepare_workloads():
     _add_workload_mean(array_pool)
     _add_workload_nonzero()
     _add_workload_ones_like(array_pool)
+    _add_workload_atleast_nd()
     _add_workload_prod(array_pool)
     _add_workload_repeat(array_pool)
     _add_workload_reshape()

tests/python/unittest/test_numpy_op.py

@@ -2121,6 +2121,60 @@ def hybrid_forward(self, F, a):
             assert_almost_equal(mx_out.asnumpy(), np_out, rtol=1e-3, atol=1e-5)
 
 
+@with_seed()
+@use_np
+def test_np_atleast_nd():
+    class TestAtleastND(HybridBlock):
+        def __init__(self, n):
+            super(TestAtleastND, self).__init__()
+            self._n = n
+
+        def hybrid_forward(self, F, *arys):
+            if self._n == 1:
+                return F.np.atleast_1d(*arys)
+            elif self._n == 2:
+                return F.np.atleast_2d(*arys)
+            elif self._n == 3:
+                return F.np.atleast_3d(*arys)
+
+    tensor_shapes = [
+        ((), (2,), (3, 4, 5)),
+        ((2, 3, 4, 5), (), (2, 3))
+    ]
+    flags = [True, False]
+    ns = [1, 2, 3]
+    dtypes = ['int32', 'int64', 'float16', 'float32', 'float64']
+    funcs = {
+        "numpy": {1: lambda *ts: _np.atleast_1d(*ts),
+                  2: lambda *ts: _np.atleast_2d(*ts),
+                  3: lambda *ts: _np.atleast_3d(*ts)},
+        "mxnet": {1: lambda *ts: np.atleast_1d(*ts),
+                  2: lambda *ts: np.atleast_2d(*ts),
+                  3: lambda *ts: np.atleast_3d(*ts)}
+    }
+    for hybridize, n, tensor_shape, dtype in \
+        itertools.product(flags, ns, tensor_shapes, dtypes):
+        test_atleast_nd = TestAtleastND(n)
+        if hybridize:
+            test_atleast_nd.hybridize()
+        if dtype in ['int32', 'int64']:
+            tensors = list(map(lambda s: np.random.randint(-1, 1, size=s, dtype=dtype), tensor_shape))
+        else:
+            tensors = list(map(lambda s: np.random.uniform(-1.0, 1.0, size=s, dtype=dtype), tensor_shape))
+        tensors_np = [t.asnumpy() for t in tensors]
+        mx_out = test_atleast_nd(*tensors)
+        np_out = funcs["numpy"][n](*tensors_np)
+        for i in range(len(tensors)):
+            assert mx_out[i].shape == np_out[i].shape
+            same(mx_out[i].asnumpy(), np_out[i])
+
+        mx_out = funcs["mxnet"][n](*tensors)
+        np_out = funcs["numpy"][n](*tensors_np)
+        for i in range(len(tensors)):
+            assert mx_out[i].shape == np_out[i].shape
+            same(mx_out[i].asnumpy(), np_out[i])
+
+
 @with_seed()
 @use_np
 def test_np_arange():