NumCpp  2.7.0
A Templatized Header Only C++ Implementation of the Python NumPy Library
norm.hpp
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1 #pragma once
29 
31 #include "NumCpp/Core/Types.hpp"
32 #include "NumCpp/NdArray.hpp"
33 #include "NumCpp/Utils/sqr.hpp"
34 
35 #include <algorithm>
36 #include <cmath>
37 #include <complex>
38 
39 namespace nc
40 {
41  //============================================================================
42  // Method Description:
50  template<typename dtype>
51  NdArray<double> norm(const NdArray<dtype>& inArray, Axis inAxis = Axis::NONE)
52  {
54 
55  double sumOfSquares = 0.0;
56  const auto function = [&sumOfSquares](dtype value) -> void
57  {
58  sumOfSquares += utils::sqr(static_cast<double>(value));
59  };
60 
61  switch (inAxis)
62  {
63  case Axis::NONE:
64  {
65  std::for_each(inArray.cbegin(), inArray.cend(), function);
66 
67  NdArray<double> returnArray = { std::sqrt(sumOfSquares) };
68  return returnArray;
69  }
70  case Axis::COL:
71  {
72  NdArray<double> returnArray(1, inArray.numRows());
73  for (uint32 row = 0; row < inArray.numRows(); ++row)
74  {
75  sumOfSquares = 0.0;
76  std::for_each(inArray.cbegin(row), inArray.cend(row), function);
77  returnArray(0, row) = std::sqrt(sumOfSquares);
78  }
79 
80  return returnArray;
81  }
82  case Axis::ROW:
83  {
84  NdArray<dtype> transposedArray = inArray.transpose();
85  NdArray<double> returnArray(1, transposedArray.numRows());
86  for (uint32 row = 0; row < transposedArray.numRows(); ++row)
87  {
88  sumOfSquares = 0.0;
89  std::for_each(transposedArray.cbegin(row), transposedArray.cend(row), function);
90  returnArray(0, row) = std::sqrt(sumOfSquares);
91  }
92 
93  return returnArray;
94  }
95  default:
96  {
97  THROW_INVALID_ARGUMENT_ERROR("Unimplemented axis type.");
98  return {}; // get rid of compiler warning
99  }
100  }
101  }
102 
103  //============================================================================
104  // Method Description:
112  template<typename dtype>
113  NdArray<std::complex<double>> norm(const NdArray<std::complex<dtype>>& inArray, Axis inAxis = Axis::NONE)
114  {
116 
117  std::complex<double> sumOfSquares(0.0, 0.0);
118  const auto function = [&sumOfSquares](const std::complex<dtype>& value) -> void
119  {
120  sumOfSquares += utils::sqr(complex_cast<double>(value));
121  };
122 
123  switch (inAxis)
124  {
125  case Axis::NONE:
126  {
127  std::for_each(inArray.cbegin(), inArray.cend(), function);
128 
129  NdArray<std::complex<double>> returnArray = { std::sqrt(sumOfSquares) };
130  return returnArray;
131  }
132  case Axis::COL:
133  {
134  NdArray<std::complex<double>> returnArray(1, inArray.numRows());
135  for (uint32 row = 0; row < inArray.numRows(); ++row)
136  {
137  sumOfSquares = std::complex<double>(0.0, 0.0);
138  std::for_each(inArray.cbegin(row), inArray.cend(row), function);
139  returnArray(0, row) = std::sqrt(sumOfSquares);
140  }
141 
142  return returnArray;
143  }
144  case Axis::ROW:
145  {
146  NdArray<std::complex<dtype>> transposedArray = inArray.transpose();
147  NdArray<std::complex<double>> returnArray(1, transposedArray.numRows());
148  for (uint32 row = 0; row < transposedArray.numRows(); ++row)
149  {
150  sumOfSquares = std::complex<double>(0.0, 0.0);
151  std::for_each(transposedArray.cbegin(row), transposedArray.cend(row), function);
152  returnArray(0, row) = std::sqrt(sumOfSquares);
153  }
154 
155  return returnArray;
156  }
157  default:
158  {
159  THROW_INVALID_ARGUMENT_ERROR("Unimplemented axis type.");
160  return {}; // get rid of compiler warning
161  }
162  }
163  }
164 } // namespace nc
#define THROW_INVALID_ARGUMENT_ERROR(msg)
Definition: Error.hpp:36
#define STATIC_ASSERT_ARITHMETIC(dtype)
Definition: StaticAsserts.hpp:37
const_iterator cbegin() const noexcept
Definition: NdArrayCore.hpp:1216
uint32 numRows() const noexcept
Definition: NdArrayCore.hpp:3430
NdArray< dtype > transpose() const
Definition: NdArrayCore.hpp:4629
const_iterator cend() const noexcept
Definition: NdArrayCore.hpp:1524
void for_each(InputIt first, InputIt last, UnaryFunction f)
Definition: StlAlgorithms.hpp:213
constexpr dtype sqr(dtype inValue) noexcept
Definition: sqr.hpp:44
Definition: Coordinate.hpp:45
Axis
Enum To describe an axis.
Definition: Types.hpp:46
auto sqrt(dtype inValue) noexcept
Definition: sqrt.hpp:48
NdArray< double > norm(const NdArray< dtype > &inArray, Axis inAxis=Axis::NONE)
Definition: norm.hpp:51
std::uint32_t uint32
Definition: Types.hpp:40