[Numpy] add polynomial polyval

python/mxnet/ndarray/numpy/_op.py

@@ -44,7 +44,7 @@
            'tril', 'identity', 'take', 'ldexp', 'vdot', 'inner', 'outer',
            'equal', 'not_equal', 'greater', 'less', 'greater_equal', 'less_equal', 'hsplit', 'rot90', 'einsum',
            'true_divide', 'nonzero', 'quantile', 'percentile', 'shares_memory', 'may_share_memory',
-           'diff', 'resize', 'nan_to_num', 'isnan', 'isinf', 'where', 'bincount']
+           'diff', 'resize', 'polyval', 'nan_to_num', 'isnan', 'isinf', 'where', 'bincount']
 
 
 @set_module('mxnet.ndarray.numpy')
@@ -203,7 +203,11 @@ def zeros_like(a, dtype=None, order='C', ctx=None, out=None):
     >>> np.zeros_like(y)
     array([0., 0., 0.], dtype=float64)
     """
-    return _npi.full_like(a, fill_value=0, dtype=dtype, ctx=None, out=None)
+    if order != 'C':
+        raise NotImplementedError
+    if ctx is None:
+        ctx = current_context()
+    return _npi.full_like(a, fill_value=0, dtype=dtype, ctx=ctx, out=out)
 
 
 @set_module('mxnet.ndarray.numpy')
@@ -259,7 +263,11 @@ def ones_like(a, dtype=None, order='C', ctx=None, out=None):
     >>> np.ones_like(y)
     array([1., 1., 1.], dtype=float64)
     """
-    return _npi.full_like(a, fill_value=1, dtype=dtype, ctx=None, out=None)
+    if order != 'C':
+        raise NotImplementedError
+    if ctx is None:
+        ctx = current_context()
+    return _npi.full_like(a, fill_value=1, dtype=dtype, ctx=ctx, out=out)
 
 
 @set_module('mxnet.ndarray.numpy')
@@ -6922,6 +6930,58 @@ def where(condition, x=None, y=None):  # pylint: disable=too-many-return-stateme
                 raise TypeError('type {0} and {1} not supported'.format(str(type(x)), str(type(y))))
 
 
+@set_module('mxnet.ndarray.numpy')
+def polyval(p, x):
+    """
+    Evaluate a polynomial at specific values.
+    If p is of length N, this function returns the value:
+    p[0]*x**(N-1) + p[1]*x**(N-2) + ... + p[N-2]*x + p[N-1]
+    If x is a sequence, then p(x) is returned for each element of x.
+    If x is another polynomial then the composite polynomial p(x(t)) is returned.
+
+    Parameters
+    ----------
+    p : ndarray
+        1D array of polynomial coefficients (including coefficients equal to zero)
+        from highest degree to the constant term.
+    x : ndarray
+        An array of numbers, at which to evaluate p.
+
+    Returns
+    -------
+    values : ndarray
+        Result array of polynomials
+
+    Notes
+    -----
+    This function differs from the original `numpy.polyval
+    <https://numpy.org/devdocs/reference/generated/numpy.polyval.html>`_ in
+    the following way(s):
+    - Does not support poly1d.
+    - X should be ndarray type even if it contains only one element.
+
+    Examples
+    --------
+    >>> p = np.array([3, 0, 1])
+    array([3., 0., 1.])
+    >>> x = np.array([5])
+    array([5.])
+    >>> np.polyval(p, x)  # 3 * 5**2 + 0 * 5**1 + 1
+    array([76.])
+    >>> x = np.array([5, 4])
+    array([5., 4.])
+    >>> np.polyval(p, x)
+    array([76., 49.])
+    """
+    from ...numpy import ndarray
+    if isinstance(p, ndarray) and isinstance(x, ndarray):
+        return _npi.polyval(p, x)
+    elif not isinstance(p, ndarray) and not isinstance(x, ndarray):
+        return _np.polyval(p, x)
+    else:
+        raise TypeError('type not supported')
+
+
 @set_module('mxnet.ndarray.numpy')
 def bincount(x, weights=None, minlength=0):
     """

python/mxnet/numpy/multiarray.py

@@ -65,7 +65,7 @@
            'unique', 'lcm', 'tril', 'identity', 'take', 'ldexp', 'vdot', 'inner', 'outer', 'equal', 'not_equal',
            'greater', 'less', 'greater_equal', 'less_equal', 'hsplit', 'rot90', 'einsum', 'true_divide', 'nonzero',
            'quantile', 'percentile', 'shares_memory', 'may_share_memory', 'diff', 'resize', 'matmul',
-           'nan_to_num', 'isnan', 'isinf', 'where', 'bincount']
+           'nan_to_num', 'isnan', 'isinf', 'polyval', 'where', 'bincount']
 
 __all__ += fallback.__all__
 
@@ -8596,7 +8596,7 @@ def full_like(a, fill_value, dtype=None, order='C', ctx=None, out=None): # pylin
     >>> np.full_like(y, 0.1)
     array([0.1, 0.1, 0.1, 0.1, 0.1, 0.1])
     """
-    return _mx_nd_np.full_like(a, fill_value=fill_value, dtype=dtype, order=order, ctx=None, out=None)
+    return _mx_nd_np.full_like(a, fill_value=fill_value, dtype=dtype, order=order, ctx=ctx, out=out)
 
 
 @set_module('mxnet.numpy')
@@ -8652,7 +8652,7 @@ def zeros_like(a, dtype=None, order='C', ctx=None, out=None):
     >>> np.zeros_like(y)
     array([0., 0., 0.], dtype=float64)
     """
-    return _mx_nd_np.full_like(a, fill_value=0, dtype=dtype, order=order, ctx=None, out=None)
+    return _mx_nd_np.full_like(a, fill_value=0, dtype=dtype, order=order, ctx=ctx, out=ctx)
 
 
 @set_module('mxnet.numpy')
@@ -8708,7 +8708,7 @@ def ones_like(a, dtype=None, order='C', ctx=None, out=None):
     >>> np.ones_like(y)
     array([1., 1., 1.], dtype=float64)
     """
-    return _mx_nd_np.full_like(a, fill_value=1, dtype=dtype, order=order, ctx=None, out=None)
+    return _mx_nd_np.full_like(a, fill_value=1, dtype=dtype, order=order, ctx=ctx, out=out)
 
 
 @set_module('mxnet.numpy')
@@ -8972,6 +8972,52 @@ def where(condition, x=None, y=None):
     return _mx_nd_np.where(condition, x, y)
 
 
+@set_module('mxnet.numpy')
+def polyval(p, x):
+    """
+    Evaluate a polynomial at specific values.
+    If p is of length N, this function returns the value:
+    p[0]*x**(N-1) + p[1]*x**(N-2) + ... + p[N-2]*x + p[N-1]
+    If x is a sequence, then p(x) is returned for each element of x.
+    If x is another polynomial then the composite polynomial p(x(t)) is returned.
+
+    Parameters
+    ----------
+    p : ndarray
+        1D array of polynomial coefficients (including coefficients equal to zero)
+        from highest degree to the constant term.
+    x : ndarray
+        An array of numbers, at which to evaluate p.
+
+    Returns
+    -------
+    values : ndarray
+        Result array of polynomials
+
+    Notes
+    -----
+    This function differs from the original `numpy.polyval
+    <https://numpy.org/devdocs/reference/generated/numpy.polyval.html>`_ in
+    the following way(s):
+    - Does not support poly1d.
+    - X should be ndarray type even if it contains only one element.
+
+    Examples
+    --------
+    >>> p = np.array([3, 0, 1])
+    array([3., 0., 1.])
+    >>> x = np.array([5])
+    array([5.])
+    >>> np.polyval(p, x)  # 3 * 5**2 + 0 * 5**1 + 1
+    array([76.])
+    >>> x = np.array([5, 4])
+    array([5., 4.])
+    >>> np.polyval(p, x)
+    array([76., 49.])
+    """
+    return _mx_nd_np.polyval(p, x)
+
+
 @set_module('mxnet.numpy')
 def bincount(x, weights=None, minlength=0):
     """

python/mxnet/numpy_dispatch_protocol.py

@@ -162,6 +162,7 @@ def _run_with_array_ufunc_proto(*args, **kwargs):
     'meshgrid',
     'outer',
     'einsum',
+    'polyval',
     'shares_memory',
     'may_share_memory',
     'quantile',

python/mxnet/symbol/numpy/_symbol.py

@@ -51,7 +51,7 @@
            'tril', 'identity', 'take', 'ldexp', 'vdot', 'inner', 'outer',
            'equal', 'not_equal', 'greater', 'less', 'greater_equal', 'less_equal', 'hsplit', 'rot90', 'einsum',
            'true_divide', 'quantile', 'percentile', 'shares_memory', 'may_share_memory', 'diff',
-           'resize', 'nan_to_num', 'isnan', 'isinf', 'where', 'bincount']
+           'resize', 'polyval', 'nan_to_num', 'isnan', 'isinf', 'where', 'bincount']
 
 
 @set_module('mxnet.symbol.numpy')
@@ -6182,6 +6182,44 @@ def load_json(json_str):
     return _Symbol(handle)
 
 
+@set_module('mxnet.symbol.numpy')
+def polyval(p, x):
+    """
+    Evaluate a polynomial at specific values.
+    If p is of length N, this function returns the value:
+    p[0]*x**(N-1) + p[1]*x**(N-2) + ... + p[N-2]*x + p[N-1]
+    If x is a sequence, then p(x) is returned for each element of x.
+    If x is another polynomial then the composite polynomial p(x(t)) is returned.
+
+    Parameters
+    ----------
+    p : _Symbol
+        1D array of polynomial coefficients (including coefficients equal to zero)
+        from highest degree to the constant term.
+    x : _Symbol
+        An array of numbers, at which to evaluate p.
+
+    Returns
+    -------
+    values : _Symbol
+        Result array of polynomials
+
+    Notes
+    -----
+    This function differs from the original `numpy.polyval
+    <https://numpy.org/devdocs/reference/generated/numpy.polyval.html>`_ in
+    the following way(s):
+    - Does not support poly1d.
+    - X should be ndarray type even if it contains only one element.
+    """
+    if isinstance(p, Symbol) and isinstance(x, Symbol):
+        return _npi.polyval(p, x)
+    elif not isinstance(p, Symbol) and not isinstance(x, Symbol):
+        return _np.polyval(p, x)
+    else:
+        raise TypeError('type not supported')
+
+
 @set_module('mxnet.symbol.numpy')
 def bincount(x, weights=None, minlength=0):
     """

src/operator/numpy/np_polynomial_op-inl.h

@@ -0,0 +1,100 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+
+/*!
+ * \file np_polynomial_op.h
+ * \brief Functions for dealing with polynomials.
+ */
+
+#ifndef MXNET_OPERATOR_NUMPY_NP_POLYNOMIAL_OP_INL_H_
+#define MXNET_OPERATOR_NUMPY_NP_POLYNOMIAL_OP_INL_H_
+
+#include <mxnet/base.h>
+#include <string>
+#include <vector>
+#include <type_traits>
+#include "../mxnet_op.h"
+#include "../../common/utils.h"
+#include "../tensor/elemwise_binary_broadcast_op.h"
+
+
+namespace mxnet {
+namespace op {
+
+inline bool NumpyPolyvalShape(const nnvm::NodeAttrs& attrs,
+                              mxnet::ShapeVector *in_attrs,
+                              mxnet::ShapeVector *out_attrs) {
+  CHECK_EQ(in_attrs->size(), 2U);
+  CHECK_EQ(out_attrs->size(), 1U);
+
+  const mxnet::TShape& p_shape = in_attrs->at(0);
+  const mxnet::TShape& x_shape = in_attrs->at(1);
+  const mxnet::TShape& v_shape = out_attrs->at(0);
+  CHECK_EQ(p_shape.ndim(), 1U) << "ValueError: p has to be an 1-D array.";
+  SHAPE_ASSIGN_CHECK(*out_attrs, 0, x_shape);
+  SHAPE_ASSIGN_CHECK(*in_attrs, 1, v_shape);
+  return shape_is_known(*in_attrs) && shape_is_known(*out_attrs);
+}
+
+template<int req>
+struct polyval_forward {
+  template<typename DType>
+  MSHADOW_XINLINE static void Map(int i,
+                                  DType* out_data,
+                                  const DType* p_data,
+                                  const DType* x_data,
+                                  const index_t p_size) {
+    DType val = 0;
+    for (index_t j = 0; j < p_size; j++) {
+        val = val * x_data[i] + p_data[j];
+    }
+    KERNEL_ASSIGN(out_data[i], req, val);
+  }
+};
+
+template<typename xpu>
+void NumpyPolyvalForward(const nnvm::NodeAttrs& attrs,
+                         const OpContext& ctx,
+                         const std::vector<TBlob>& inputs,
+                         const std::vector<OpReqType>& req,
+                         const std::vector<TBlob>& outputs) {
+  using namespace mxnet;
+  CHECK_EQ(inputs.size(), 2U);
+  CHECK_EQ(outputs.size(), 1U);
+  CHECK_EQ(req.size(), 1U);
+  mshadow::Stream<xpu> *s = ctx.get_stream<xpu>();
+  const TBlob& p_data = inputs[0];
+  const TBlob& x_data = inputs[1];
+  const TBlob& out_data = outputs[0];
+  const size_t p_size = p_data.Size();
+  using namespace mxnet_op;
+
+  MSHADOW_TYPE_SWITCH(x_data.type_flag_, DType, {
+    MXNET_ASSIGN_REQ_SWITCH(req[0], req_type, {
+      Kernel<polyval_forward<req_type>, xpu>::Launch(
+          s, out_data.Size(), out_data.dptr<DType>(),
+          p_data.dptr<DType>(), x_data.dptr<DType>(), p_size);
+    });
+  });
+}
+
+}  // namespace op
+}  // namespace mxnet
+
+#endif  // MXNET_OPERATOR_NUMPY_NP_POLYNOMIAL_OP_INL_H_