interp

python/mxnet/ndarray/numpy/_op.py

@@ -44,7 +44,7 @@
            'hypot', 'bitwise_and', 'bitwise_xor', 'bitwise_or', 'rad2deg', 'deg2rad', 'unique', 'lcm',
            'tril', 'identity', 'take', 'ldexp', 'vdot', 'inner', 'outer',
            'equal', 'not_equal', 'greater', 'less', 'greater_equal', 'less_equal', 'rot90', 'einsum',
-           'true_divide', 'nonzero', 'quantile', 'percentile', 'shares_memory', 'may_share_memory',
+           'true_divide', 'nonzero', 'quantile', 'percentile', 'shares_memory', 'may_share_memory', 'interp',
            'diff', 'ediff1d', 'resize', 'polyval', 'nan_to_num', 'isnan', 'isinf', 'isposinf', 'isneginf', 'isfinite',
            'where', 'bincount', 'pad', 'cumsum']
 
@@ -6803,6 +6803,86 @@ def may_share_memory(a, b, max_work=None):
     return _npi.share_memory(a, b).item()
 
 
+@set_module('mxnet.ndarray.numpy')
+def interp(x, xp, fp, left=None, right=None, period=None):  # pylint: disable=too-many-arguments
+    """
+    One-dimensional linear interpolation.
+    Returns the one-dimensional piecewise linear interpolant to a function
+    with given values at discrete data-points.
+
+    Parameters
+    ----------
+    x : ndarray
+        The x-coordinates of the interpolated values.
+    xp : 1-D array of floats
+        The x-coordinates of the data points, must be increasing if argument
+        `period` is not specified. Otherwise, `xp` is internally sorted after
+        normalizing the periodic boundaries with ``xp = xp % period``.
+    fp : 1-D array of floats
+        The y-coordinates of the data points, same length as `xp`.
+    left : optional float corresponding to fp
+        Value to return for `x < xp[0]`, default is `fp[0]`.
+    right : optional float corresponding to fp
+        Value to return for `x > xp[-1]`, default is `fp[-1]`.
+    period : None or float, optional
+        A period for the x-coordinates. This parameter allows the proper
+        interpolation of angular x-coordinates. Parameters `left` and `right`
+        are ignored if `period` is specified.
+        .. versionadded:: 1.10.0
+
+    Returns
+    -------
+    y : float (corresponding to fp) or ndarray
+        The interpolated values, same shape as `x`.
+    Raises
+    ------
+    ValueError
+        If `xp` and `fp` have different length
+        If `xp` or `fp` are not 1-D sequences
+        If `period == 0`
+
+    Notes
+    -----
+    Does not check that the x-coordinate sequence `xp` is increasing.
+    If `xp` is not increasing, the results are nonsense.
+    A simple check for increasing is::
+        np.all(np.diff(xp) > 0)
+
+    Examples
+    --------
+    >>> xp = [1, 2, 3]
+    >>> fp = [3, 2, 0]
+    >>> np.interp(2.5, xp, fp)
+    1.0
+    >>> np.interp([0, 1, 1.5, 2.72, 3.14], xp, fp)
+    array([ 3. ,  3. ,  2.5 ,  0.56,  0. ])
+    >>> UNDEF = -99.0
+    >>> np.interp(3.14, xp, fp, right=UNDEF)
+    -99.0
+    Plot an interpolant to the sine function:
+    >>> x = np.linspace(0, 2*np.pi, 10)
+    >>> y = np.sin(x)
+    >>> xvals = np.linspace(0, 2*np.pi, 50)
+    >>> yinterp = np.interp(xvals, x, y)
+    >>> import matplotlib.pyplot as plt
+    >>> plt.plot(x, y, 'o')
+    [<matplotlib.lines.Line2D object at 0x...>]
+    >>> plt.plot(xvals, yinterp, '-x')
+    [<matplotlib.lines.Line2D object at 0x...>]
+    >>> plt.show()
+    Interpolation with periodic x-coordinates:
+    >>> x = [-180, -170, -185, 185, -10, -5, 0, 365]
+    >>> xp = [190, -190, 350, -350]
+    >>> fp = [5, 10, 3, 4]
+    >>> np.interp(x, xp, fp, period=360)
+    array([7.5, 5., 8.75, 6.25, 3., 3.25, 3.5, 3.75])
+    """
+    if not isinstance(x, numeric_types):
+        x = x.astype(float)
+    return _api_internal.interp(xp.astype(float), fp.astype(float), x, left,
+                                right, period)
+
+
 @set_module('mxnet.ndarray.numpy')
 def diff(a, n=1, axis=-1, prepend=None, append=None):  # pylint: disable=redefined-outer-name
     r"""

python/mxnet/numpy/fallback.py

@@ -50,7 +50,6 @@
     'histogramdd',
     'i0',
     'in1d',
-    'interp',
     'intersect1d',
     'isclose',
     'isin',
@@ -138,7 +137,6 @@
 histogramdd = onp.histogramdd
 i0 = onp.i0
 in1d = onp.in1d
-interp = onp.interp
 intersect1d = onp.intersect1d
 isclose = onp.isclose
 isin = onp.isin

python/mxnet/numpy/multiarray.py

@@ -64,7 +64,7 @@
            'flip', 'flipud', 'fliplr', 'around', 'round', 'round_', 'arctan2', 'hypot',
            'bitwise_and', 'bitwise_xor', 'bitwise_or', 'rad2deg', 'deg2rad',
            'unique', 'lcm', 'tril', 'identity', 'take', 'ldexp', 'vdot', 'inner', 'outer', 'equal', 'not_equal',
-           'greater', 'less', 'greater_equal', 'less_equal', 'rot90', 'einsum', 'true_divide', 'nonzero',
+           'greater', 'less', 'greater_equal', 'less_equal', 'rot90', 'einsum', 'true_divide', 'nonzero', 'interp',
            'quantile', 'percentile', 'shares_memory', 'may_share_memory', 'diff', 'ediff1d', 'resize', 'matmul',
            'nan_to_num', 'isnan', 'isinf', 'isposinf', 'isneginf', 'isfinite', 'polyval', 'where', 'bincount',
            'pad', 'cumsum']
@@ -8954,6 +8954,83 @@ def resize(a, new_shape):
     return _mx_nd_np.resize(a, new_shape)
 
 
+@set_module('mxnet.numpy')
+def interp(x, xp, fp, left=None, right=None, period=None):  # pylint: disable=too-many-arguments
+    """
+    One-dimensional linear interpolation.
+    Returns the one-dimensional piecewise linear interpolant to a function
+    with given values at discrete data-points.
+
+    Parameters
+    ----------
+    x : ndarray
+        The x-coordinates of the interpolated values.
+    xp : 1-D array of floats
+        The x-coordinates of the data points, must be increasing if argument
+        `period` is not specified. Otherwise, `xp` is internally sorted after
+        normalizing the periodic boundaries with ``xp = xp % period``.
+    fp : 1-D array of floats
+        The y-coordinates of the data points, same length as `xp`.
+    left : optional float corresponding to fp
+        Value to return for `x < xp[0]`, default is `fp[0]`.
+    right : optional float corresponding to fp
+        Value to return for `x > xp[-1]`, default is `fp[-1]`.
+    period : None or float, optional
+        A period for the x-coordinates. This parameter allows the proper
+        interpolation of angular x-coordinates. Parameters `left` and `right`
+        are ignored if `period` is specified.
+        .. versionadded:: 1.10.0
+
+    Returns
+    -------
+    y : float (corresponding to fp) or ndarray
+        The interpolated values, same shape as `x`.
+    Raises
+    ------
+    ValueError
+        If `xp` and `fp` have different length
+        If `xp` or `fp` are not 1-D sequences
+        If `period == 0`
+
+    Notes
+    -----
+    Does not check that the x-coordinate sequence `xp` is increasing.
+    If `xp` is not increasing, the results are nonsense.
+    A simple check for increasing is::
+        np.all(np.diff(xp) > 0)
+
+    Examples
+    --------
+    >>> xp = [1, 2, 3]
+    >>> fp = [3, 2, 0]
+    >>> np.interp(2.5, xp, fp)
+    1.0
+    >>> np.interp([0, 1, 1.5, 2.72, 3.14], xp, fp)
+    array([ 3. ,  3. ,  2.5 ,  0.56,  0. ])
+    >>> UNDEF = -99.0
+    >>> np.interp(3.14, xp, fp, right=UNDEF)
+    -99.0
+    Plot an interpolant to the sine function:
+    >>> x = np.linspace(0, 2*np.pi, 10)
+    >>> y = np.sin(x)
+    >>> xvals = np.linspace(0, 2*np.pi, 50)
+    >>> yinterp = np.interp(xvals, x, y)
+    >>> import matplotlib.pyplot as plt
+    >>> plt.plot(x, y, 'o')
+    [<matplotlib.lines.Line2D object at 0x...>]
+    >>> plt.plot(xvals, yinterp, '-x')
+    [<matplotlib.lines.Line2D object at 0x...>]
+    >>> plt.show()
+    Interpolation with periodic x-coordinates:
+    >>> x = [-180, -170, -185, 185, -10, -5, 0, 365]
+    >>> xp = [190, -190, 350, -350]
+    >>> fp = [5, 10, 3, 4]
+    >>> np.interp(x, xp, fp, period=360)
+    array([7.5, 5., 8.75, 6.25, 3., 3.25, 3.5, 3.75])
+    """
+    return _mx_nd_np.interp(x, xp, fp, left=left, right=right, period=period)
+
+
 # pylint: disable=redefined-outer-name
 @set_module('mxnet.numpy')
 def full_like(a, fill_value, dtype=None, order='C', ctx=None, out=None): # pylint: disable=too-many-arguments

python/mxnet/numpy_dispatch_protocol.py

@@ -110,6 +110,7 @@ def _run_with_array_ufunc_proto(*args, **kwargs):
     'fliplr',
     'inner',
     'insert',
+    'interp',
     'max',
     'amax',
     'mean',

python/mxnet/symbol/numpy/_symbol.py

@@ -48,7 +48,7 @@
            'diag_indices_from', 'hanning', 'hamming', 'blackman', 'flip', 'flipud', 'fliplr',
            'hypot', 'bitwise_and', 'bitwise_xor', 'bitwise_or', 'rad2deg', 'deg2rad', 'unique', 'lcm',
            'tril', 'identity', 'take', 'ldexp', 'vdot', 'inner', 'outer',
-           'equal', 'not_equal', 'greater', 'less', 'greater_equal', 'less_equal', 'rot90', 'einsum',
+           'equal', 'not_equal', 'greater', 'less', 'greater_equal', 'less_equal', 'rot90', 'einsum', 'interp',
            'true_divide', 'quantile', 'percentile', 'shares_memory', 'may_share_memory', 'diff', 'ediff1d',
            'resize', 'polyval', 'nan_to_num', 'isnan', 'isinf', 'isposinf', 'isneginf', 'isfinite',
            'where', 'bincount', 'pad', 'cumsum']
@@ -6151,6 +6151,59 @@ def ediff1d(ary, to_end=None, to_begin=None):
                             to_begin_scalar=to_begin, to_end_scalar=to_end)
 
 
+@set_module('mxnet.symbol.numpy')
+def interp(x, xp, fp, left=None, right=None, period=None):  # pylint: disable=too-many-arguments
+    """
+    One-dimensional linear interpolation.
+    Returns the one-dimensional piecewise linear interpolant to a function
+    with given values at discrete data-points.
+
+    Parameters
+    ----------
+    x : _Symbol
+        The x-coordinates of the interpolated values.
+    xp : _Symbol
+        The x-coordinates of the data points, must be increasing if argument
+        `period` is not specified. Otherwise, `xp` is internally sorted after
+        normalizing the periodic boundaries with ``xp = xp % period``.
+    fp : _Symbol
+        The y-coordinates of the data points, same length as `xp`.
+    left : optional float corresponding to fp
+        Value to return for `x < xp[0]`, default is `fp[0]`.
+    right : optional float corresponding to fp
+        Value to return for `x > xp[-1]`, default is `fp[-1]`.
+    period : None or float, optional
+        A period for the x-coordinates. This parameter allows the proper
+        interpolation of angular x-coordinates. Parameters `left` and `right`
+        are ignored if `period` is specified.
+        .. versionadded:: 1.10.0
+
+    Returns
+    -------
+    y : _Symbol
+        The interpolated values, same shape as `x`.
+
+    Raises
+    ------
+    ValueError
+        If `xp` and `fp` have different length
+        If `xp` or `fp` are not 1-D sequences
+        If `period == 0`
+
+    Notes
+    -----
+    Does not check that the x-coordinate sequence `xp` is increasing.
+    If `xp` is not increasing, the results are nonsense.
+    A simple check for increasing is::
+        np.all(np.diff(xp) > 0)
+    """
+    if isinstance(x, numeric_types):
+        return _npi.interp(xp.astype(float), fp.astype(float), left=left,
+                           right=right, period=period, x_scalar=x)
+    return _npi.interp(xp.astype(float), fp.astype(float), x.astype(float),
+                       left=left, right=right, period=period, x_scalar=None)
+
+
 @set_module('mxnet.symbol.numpy')
 def resize(a, new_shape):
     """

src/api/operator/numpy/np_interp_op.cc

@@ -0,0 +1,74 @@
+/*
+ * 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_interp_op.cc
+ * \brief Implementation of the API of functions in src/operator/numpy/np_interp_op.cc
+ */
+#include <mxnet/api_registry.h>
+#include <mxnet/runtime/packed_func.h>
+#include "../utils.h"
+#include "../../../operator/numpy/np_interp_op-inl.h"
+
+namespace mxnet {
+
+MXNET_REGISTER_API("_npi.interp")
+.set_body([](runtime::MXNetArgs args, runtime::MXNetRetValue* ret) {
+  using namespace runtime;
+  const nnvm::Op* op = Op::Get("_npi_interp");
+  nnvm::NodeAttrs attrs;
+  op::NumpyInterpParam param;
+  if (args[3].type_code() == kNull) {
+    param.left = dmlc::nullopt;
+  } else {
+    param.left = args[3].operator double();
+  }
+  if (args[4].type_code() == kNull) {
+    param.right = dmlc::nullopt;
+  } else {
+    param.right = args[4].operator double();
+  }
+  if (args[5].type_code() == kNull) {
+    param.period = dmlc::nullopt;
+  } else {
+    param.period = args[5].operator double();
+  }
+  if (args[2].type_code() == kDLInt || args[2].type_code() == kDLFloat) {
+    param.x_scalar = args[2].operator double();
+    attrs.op = op;
+    attrs.parsed = std::move(param);
+    SetAttrDict<op::NumpyInterpParam>(&attrs);
+    int num_outputs = 0;
+    NDArray* inputs[] = {args[0].operator mxnet::NDArray*(), args[1].operator mxnet::NDArray*()};
+    auto ndoutputs = Invoke(op, &attrs, 2, inputs, &num_outputs, nullptr);
+    *ret = reinterpret_cast<mxnet::NDArray*>(ndoutputs[0]);
+  } else {
+    param.x_scalar = dmlc::nullopt;
+    attrs.op = op;
+    attrs.parsed = std::move(param);
+    SetAttrDict<op::NumpyInterpParam>(&attrs);
+    int num_outputs = 0;
+    NDArray* inputs[] = {args[0].operator mxnet::NDArray*(), args[1].operator mxnet::NDArray*(),
+                         args[2].operator mxnet::NDArray*()};
+    auto ndoutputs = Invoke(op, &attrs, 3, inputs, &num_outputs, nullptr);
+    *ret = reinterpret_cast<mxnet::NDArray*>(ndoutputs[0]);
+  }
+});
+
+}  // namespace mxnet