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0001 /// \file ROOT/RNTupleInspector.hxx 0002 /// \ingroup NTuple ROOT7 0003 /// \author Florine de Geus <florine.de.geus@cern.ch> 0004 /// \date 2023-01-09 0005 /// \warning This is part of the ROOT 7 prototype! It will change without notice. It might trigger earthquakes. Feedback 0006 /// is welcome! 0007 0008 /************************************************************************* 0009 * Copyright (C) 1995-2023, Rene Brun and Fons Rademakers. * 0010 * All rights reserved. * 0011 * * 0012 * For the licensing terms see $ROOTSYS/LICENSE. * 0013 * For the list of contributors see $ROOTSYS/README/CREDITS. * 0014 *************************************************************************/ 0015 0016 #ifndef ROOT7_RNTupleInspector 0017 #define ROOT7_RNTupleInspector 0018 0019 #include <ROOT/RError.hxx> 0020 #include <ROOT/RNTupleDescriptor.hxx> 0021 0022 #include <TFile.h> 0023 #include <TH1D.h> 0024 #include <THStack.h> 0025 0026 #include <cstdlib> 0027 #include <iostream> 0028 #include <memory> 0029 #include <numeric> 0030 #include <regex> 0031 #include <vector> 0032 0033 namespace ROOT { 0034 namespace Experimental { 0035 0036 class RNTuple; 0037 0038 namespace Internal { 0039 class RPageSource; 0040 } // namespace Internal 0041 0042 enum class ENTupleInspectorPrintFormat { kTable, kCSV }; 0043 enum class ENTupleInspectorHist { kCount, kNElems, kCompressedSize, kUncompressedSize }; 0044 0045 // clang-format off 0046 /** 0047 \class ROOT::Experimental::RNTupleInspector 0048 \ingroup NTuple 0049 \brief Inspect on-disk and storage-related information of an RNTuple. 0050 0051 The RNTupleInspector can be used for studying an RNTuple in terms of its storage efficiency. It provides information on 0052 the level of the RNTuple itself, on the (sub)field level and on the column level. 0053 0054 Example usage: 0055 0056 ~~~ {.cpp} 0057 #include <ROOT/RNTuple.hxx> 0058 #include <ROOT/RNTupleInspector.hxx> 0059 0060 #include <iostream> 0061 0062 using ROOT::Experimental::RNTuple; 0063 using ROOT::Experimental::RNTupleInspector; 0064 0065 auto file = TFile::Open("data.rntuple"); 0066 auto rntuple = file->Get<RNTuple>("NTupleName"); 0067 auto inspector = RNTupleInspector::Create(rntuple).Unwrap(); 0068 0069 std::cout << "The compression factor is " << inspector->GetCompressionFactor() 0070 << " using compression settings " << inspector->GetCompressionSettings() 0071 << std::endl; 0072 ~~~ 0073 */ 0074 // clang-format on 0075 class RNTupleInspector { 0076 public: 0077 ///////////////////////////////////////////////////////////////////////////// 0078 /// \brief Provides column-level storage information. 0079 /// 0080 /// The RColumnInspector class provides storage information for an individual column. This information is partly 0081 /// collected during the construction of the RNTupleInspector object, and can partly be accessed using the 0082 /// RColumnInspector that belongs to this field. 0083 class RColumnInspector { 0084 private: 0085 const RColumnDescriptor &fColumnDescriptor; 0086 const std::vector<std::uint64_t> fCompressedPageSizes = {}; 0087 std::uint32_t fElementSize = 0; 0088 std::uint64_t fNElements = 0; 0089 0090 public: 0091 RColumnInspector(const RColumnDescriptor &colDesc, const std::vector<std::uint64_t> &compressedPageSizes, 0092 std::uint32_t elemSize, std::uint64_t nElems) 0093 : fColumnDescriptor(colDesc), 0094 fCompressedPageSizes(compressedPageSizes), 0095 fElementSize(elemSize), 0096 fNElements(nElems){}; 0097 ~RColumnInspector() = default; 0098 0099 const RColumnDescriptor &GetDescriptor() const { return fColumnDescriptor; } 0100 const std::vector<std::uint64_t> &GetCompressedPageSizes() const { return fCompressedPageSizes; } 0101 std::uint64_t GetNPages() const { return fCompressedPageSizes.size(); } 0102 std::uint64_t GetCompressedSize() const 0103 { 0104 return std::accumulate(fCompressedPageSizes.begin(), fCompressedPageSizes.end(), 0); 0105 } 0106 std::uint64_t GetUncompressedSize() const { return fElementSize * fNElements; } 0107 std::uint64_t GetElementSize() const { return fElementSize; } 0108 std::uint64_t GetNElements() const { return fNElements; } 0109 EColumnType GetType() const { return fColumnDescriptor.GetModel().GetType(); } 0110 }; 0111 0112 ///////////////////////////////////////////////////////////////////////////// 0113 /// \brief Provides field-level storage information. 0114 /// 0115 /// The RFieldTreeInspector class provides storage information for a field **and** its subfields. This information is 0116 /// partly collected during the construction of the RNTupleInspector object, and can partly be accessed using 0117 /// the RFieldDescriptor that belongs to this field. 0118 class RFieldTreeInspector { 0119 private: 0120 const RFieldDescriptor &fRootFieldDescriptor; 0121 std::uint64_t fCompressedSize = 0; 0122 std::uint64_t fUncompressedSize = 0; 0123 0124 public: 0125 RFieldTreeInspector(const RFieldDescriptor &fieldDesc, std::uint64_t onDiskSize, std::uint64_t inMemSize) 0126 : fRootFieldDescriptor(fieldDesc), fCompressedSize(onDiskSize), fUncompressedSize(inMemSize){}; 0127 ~RFieldTreeInspector() = default; 0128 0129 const RFieldDescriptor &GetDescriptor() const { return fRootFieldDescriptor; } 0130 std::uint64_t GetCompressedSize() const { return fCompressedSize; } 0131 std::uint64_t GetUncompressedSize() const { return fUncompressedSize; } 0132 }; 0133 0134 private: 0135 std::unique_ptr<Internal::RPageSource> fPageSource; 0136 std::unique_ptr<RNTupleDescriptor> fDescriptor; 0137 int fCompressionSettings = -1; 0138 std::uint64_t fCompressedSize = 0; 0139 std::uint64_t fUncompressedSize = 0; 0140 0141 std::unordered_map<int, RColumnInspector> fColumnInfo; 0142 std::unordered_map<int, RFieldTreeInspector> fFieldTreeInfo; 0143 0144 RNTupleInspector(std::unique_ptr<Internal::RPageSource> pageSource); 0145 0146 ///////////////////////////////////////////////////////////////////////////// 0147 /// \brief Gather column-level and RNTuple-level information. 0148 /// 0149 /// \note This method is called when the RNTupleInspector is initially created. This means that anything unexpected 0150 /// about the RNTuple itself (e.g. inconsistent compression settings across clusters) will be detected here. 0151 /// Therefore, any related exceptions will be thrown on creation of the inspector. 0152 void CollectColumnInfo(); 0153 0154 ///////////////////////////////////////////////////////////////////////////// 0155 /// \brief Recursively gather field-level information. 0156 /// 0157 /// \param[in] fieldId The ID of the field from which to start the recursive traversal. Typically this is the "zero 0158 /// ID", i.e. the logical parent of all top-level fields. 0159 /// 0160 /// \return The RFieldTreeInspector for the provided field ID. 0161 /// 0162 /// This method is called when the RNTupleInspector is initially created. 0163 RFieldTreeInspector CollectFieldTreeInfo(DescriptorId_t fieldId); 0164 0165 ///////////////////////////////////////////////////////////////////////////// 0166 /// \brief Get the columns that make up the given field, including its subfields. 0167 /// 0168 /// \param [in] fieldId The ID of the field for which to collect the columns. 0169 /// 0170 /// \return A vector containing the IDs of all columns for the provided field ID. 0171 std::vector<DescriptorId_t> GetColumnsByFieldId(DescriptorId_t fieldId) const; 0172 0173 public: 0174 RNTupleInspector(const RNTupleInspector &other) = delete; 0175 RNTupleInspector &operator=(const RNTupleInspector &other) = delete; 0176 RNTupleInspector(RNTupleInspector &&other) = delete; 0177 RNTupleInspector &operator=(RNTupleInspector &&other) = delete; 0178 ~RNTupleInspector() = default; 0179 0180 ///////////////////////////////////////////////////////////////////////////// 0181 /// \brief Create a new RNTupleInspector. 0182 /// 0183 /// \param[in] sourceNTuple A pointer to the RNTuple to be inspected. 0184 /// 0185 /// \return A pointer to the newly created RNTupleInspector. 0186 /// 0187 /// \note When this factory method is called, all required static information is collected from the RNTuple's fields 0188 /// and underlying columns are collected at ones. This means that when any inconsistencies are encountered (e.g. 0189 /// inconsistent compression across clusters), it will throw an error here. 0190 static std::unique_ptr<RNTupleInspector> Create(RNTuple *sourceNTuple); 0191 0192 ///////////////////////////////////////////////////////////////////////////// 0193 /// \brief Create a new RNTupleInspector. 0194 /// 0195 /// \param[in] ntupleName The name of the RNTuple to be inspected. 0196 /// \param[in] storage The path or URI to the RNTuple to be inspected. 0197 /// 0198 /// \see Create(RNTuple *sourceNTuple) 0199 static std::unique_ptr<RNTupleInspector> Create(std::string_view ntupleName, std::string_view storage); 0200 0201 ///////////////////////////////////////////////////////////////////////////// 0202 /// \brief Get the descriptor for the RNTuple being inspected. 0203 /// 0204 /// \return A static copy of the RNTupleDescriptor belonging to the inspected RNTuple. 0205 RNTupleDescriptor *GetDescriptor() const { return fDescriptor.get(); } 0206 0207 ///////////////////////////////////////////////////////////////////////////// 0208 /// \brief Get the compression settings of the RNTuple being inspected. 0209 /// 0210 /// \return The integer representation (\f$algorithm * 10 + level\f$, where \f$algorithm\f$ follows 0211 /// ROOT::RCompressionSetting::ELevel::EValues) of the compression settings used for the inspected RNTuple. 0212 /// 0213 /// \note Here, we assume that the compression settings are consistent across all clusters and columns. If this is 0214 /// not the case, an exception will be thrown when RNTupleInspector::Create is called. 0215 int GetCompressionSettings() const { return fCompressionSettings; } 0216 0217 ///////////////////////////////////////////////////////////////////////////// 0218 /// \brief Get a string describing compression settings of the RNTuple being inspected. 0219 /// 0220 /// \return A string describing the compression used for the inspected RNTuple. The format of the string is 0221 /// `"A (level L)"`, where `A` is the name of the compression algorithm and `L` the compression level. 0222 /// 0223 /// \note Here, we assume that the compression settings are consistent across all clusters and columns. If this is 0224 /// not the case, an exception will be thrown when RNTupleInspector::Create is called. 0225 std::string GetCompressionSettingsAsString() const; 0226 0227 ///////////////////////////////////////////////////////////////////////////// 0228 /// \brief Get the compressed, on-disk size of the RNTuple being inspected. 0229 /// 0230 /// \return The compressed size of the inspected RNTuple, in bytes, excluding the size of the header and footer. 0231 std::uint64_t GetCompressedSize() const { return fCompressedSize; } 0232 0233 ///////////////////////////////////////////////////////////////////////////// 0234 /// \brief Get the uncompressed total size of the RNTuple being inspected. 0235 /// 0236 /// \return The uncompressed size of the inspected RNTuple, in bytes, excluding the size of the header and footer. 0237 std::uint64_t GetUncompressedSize() const { return fUncompressedSize; } 0238 0239 ///////////////////////////////////////////////////////////////////////////// 0240 /// \brief Get the compression factor of the RNTuple being inspected. 0241 /// 0242 /// \return The compression factor of the inspected RNTuple. 0243 /// 0244 /// The compression factor shows how well the data present in the RNTuple is compressed by the compression settings 0245 /// that were used. The compression factor is calculated as \f$size_{uncompressed} / size_{compressed}\f$. 0246 float GetCompressionFactor() const { return (float)fUncompressedSize / (float)fCompressedSize; } 0247 0248 ///////////////////////////////////////////////////////////////////////////// 0249 /// \brief Get storage information for a given column. 0250 /// 0251 /// \param[in] physicalColumnId The physical ID of the column for which to get the information. 0252 /// 0253 /// \return The storage information for the provided column. 0254 const RColumnInspector &GetColumnInspector(DescriptorId_t physicalColumnId) const; 0255 0256 ///////////////////////////////////////////////////////////////////////////// 0257 /// \brief Get the number of columns of a given type present in the RNTuple. 0258 /// 0259 /// \param[in] colType The column type to count, as defined by ROOT::Experimental::EColumnType. 0260 /// 0261 /// \return The number of columns present in the inspected RNTuple of the provided type. 0262 size_t GetColumnCountByType(EColumnType colType) const; 0263 0264 ///////////////////////////////////////////////////////////////////////////// 0265 /// \brief Get the IDs of all columns with the given type. 0266 /// 0267 /// \param[in] colType The column type to collect, as defined by ROOT::Experimental::EColumnType. 0268 /// 0269 /// \return A vector containing the physical IDs of columns of the provided type. 0270 const std::vector<DescriptorId_t> GetColumnsByType(EColumnType colType); 0271 0272 ///////////////////////////////////////////////////////////////////////////// 0273 /// \brief Get all column types present in the RNTuple being inspected. 0274 /// 0275 /// \return A vector containing all column types present in the RNTuple. 0276 const std::vector<EColumnType> GetColumnTypes(); 0277 0278 ///////////////////////////////////////////////////////////////////////////// 0279 /// \brief Print storage information per column type. 0280 /// 0281 /// \param[in] format Whether to print the information as a (markdown-parseable) table or in CSV format. 0282 /// \param[in] output Where to write the output to. Default is `stdout`. 0283 /// 0284 /// The output includes for each column type its count, the total number of elements, the compressed size and the 0285 /// uncompressed size. 0286 /// 0287 /// **Example: printing the column type information of an RNTuple as a table** 0288 /// ~~~ {.cpp} 0289 /// #include <ROOT/RNTupleInspector.hxx> 0290 /// using ROOT::Experimental::RNTupleInspector; 0291 /// using ROOT::Experimental::ENTupleInspectorPrintFormat; 0292 /// 0293 /// auto inspector = RNTupleInspector::Create("myNTuple", "some/file.root"); 0294 /// inspector->PrintColumnTypeInfo(); 0295 /// ~~~ 0296 /// Output: 0297 /// ~~~ 0298 /// column type | count | # elements | compressed bytes | uncompressed bytes 0299 /// ----------------|---------|-----------------|-------------------|-------------------- 0300 /// SplitIndex64 | 2 | 150 | 72 | 1200 0301 /// SplitReal32 | 4 | 300 | 189 | 1200 0302 /// SplitUInt32 | 3 | 225 | 123 | 900 0303 /// ~~~ 0304 /// 0305 /// **Example: printing the column type information of an RNTuple in CSV format** 0306 /// ~~~ {.cpp} 0307 /// #include <ROOT/RNTupleInspector.hxx> 0308 /// using ROOT::Experimental::RNTupleInspector; 0309 /// using ROOT::Experimental::ENTupleInspectorPrintFormat; 0310 /// 0311 /// auto inspector = RNTupleInspector::Create("myNTuple", "some/file.root"); 0312 /// inspector->PrintColumnTypeInfo(); 0313 /// ~~~ 0314 /// Output: 0315 /// ~~~ 0316 /// columnType,count,nElements,compressedSize,uncompressedSize 0317 /// SplitIndex64,2,150,72,1200 0318 /// SplitReal32,4,300,189,1200 0319 /// SplitUInt32,3,225,123,900 0320 /// ~~~ 0321 void PrintColumnTypeInfo(ENTupleInspectorPrintFormat format = ENTupleInspectorPrintFormat::kTable, 0322 std::ostream &output = std::cout); 0323 0324 ///////////////////////////////////////////////////////////////////////////// 0325 /// \brief Get a histogram showing information for each column type present, 0326 /// 0327 /// \param[in] histKind Which type of information should be returned. 0328 /// \param[in] histName The name of the histogram. An empty string means a default name will be used. 0329 /// \param[in] histTitle The title of the histogram. An empty string means a default title will be used. 0330 /// 0331 /// \return A pointer to a `TH1D` containing the specified kind of information. 0332 /// 0333 /// Get a histogram showing the count, number of elements, size on disk, or size in memory for each column 0334 /// type present in the inspected RNTuple. 0335 std::unique_ptr<TH1D> GetColumnTypeInfoAsHist(ENTupleInspectorHist histKind, std::string_view histName = "", 0336 std::string_view histTitle = ""); 0337 0338 ///////////////////////////////////////////////////////////////////////////// 0339 /// \brief Get a histogram containing the size distribution of the compressed pages for an individual column. 0340 /// 0341 /// \param[in] physicalColumnId The physical ID of the column for which to get the page size distribution. 0342 /// \param[in] histName The name of the histogram. An empty string means a default name will be used. 0343 /// \param[in] histTitle The title of the histogram. An empty string means a default title will be used. 0344 /// \param[in] nBins The desired number of histogram bins. 0345 /// 0346 /// \return A pointer to a `TH1D` containing the page size distribution. 0347 /// 0348 /// The x-axis will range from the smallest page size, to the largest (inclusive). 0349 std::unique_ptr<TH1D> GetPageSizeDistribution(DescriptorId_t physicalColumnId, std::string histName = "", 0350 std::string histTitle = "", size_t nBins = 64); 0351 0352 ///////////////////////////////////////////////////////////////////////////// 0353 /// \brief Get a histogram containing the size distribution of the compressed pages for all columns of a given type. 0354 /// 0355 /// \param[in] colType The column type for which to get the size distribution, as defined by 0356 /// ROOT::Experimental::EColumnType. 0357 /// \param[in] histName The name of the histogram. An empty string means a default name will be used. 0358 /// \param[in] histTitle The title of the histogram. An empty string means a default title will be used. 0359 /// \param[in] nBins The desired number of histogram bins. 0360 /// 0361 /// \return A pointer to a `TH1D` containing the page size distribution. 0362 /// 0363 /// The x-axis will range from the smallest page size, to the largest (inclusive). 0364 std::unique_ptr<TH1D> GetPageSizeDistribution(EColumnType colType, std::string histName = "", 0365 std::string histTitle = "", size_t nBins = 64); 0366 0367 ///////////////////////////////////////////////////////////////////////////// 0368 /// \brief Get a histogram containing the size distribution of the compressed pages for a collection columns. 0369 /// 0370 /// \param[in] colIds The physical IDs of the columns for which to get the page size distribution. 0371 /// \param[in] histName The name of the histogram. An empty string means a default name will be used. 0372 /// \param[in] histTitle The title of the histogram. An empty string means a default title will be used. 0373 /// \param[in] nBins The desired number of histogram bins. 0374 /// 0375 /// \return A pointer to a `TH1D` containing the (cumulative) page size distribution. 0376 /// 0377 /// The x-axis will range from the smallest page size, to the largest (inclusive). 0378 std::unique_ptr<TH1D> GetPageSizeDistribution(std::initializer_list<DescriptorId_t> colIds, 0379 std::string histName = "", std::string histTitle = "", 0380 size_t nBins = 64); 0381 0382 ///////////////////////////////////////////////////////////////////////////// 0383 /// \brief Get a histogram containing the size distribution of the compressed pages for all columns of a given list 0384 /// of types. 0385 /// 0386 /// \param[in] colTypes The column types for which to get the size distribution, as defined by 0387 /// ROOT::Experimental::EColumnType. The default is an empty vector, which indicates that the distribution for *all* 0388 /// physical columns will be returned. 0389 /// \param[in] histName The name of the histogram. An empty string means a default name will be used. The name of 0390 /// each histogram inside the `THStack` will be `histName + colType`. 0391 /// \param[in] histTitle The title of the histogram. An empty string means a default title will be used. 0392 /// \param[in] nBins The desired number of histogram bins. 0393 /// 0394 /// \return A pointer to a `THStack` with one histogram for each column type. 0395 /// 0396 /// The x-axis will range from the smallest page size, to the largest (inclusive). 0397 /// 0398 /// **Example: Drawing a non-stacked page size distribution with a legend** 0399 /// ~~~ {.cpp} 0400 /// auto canvas = std::make_unique<TCanvas>(); 0401 /// auto inspector = RNTupleInspector::Create("myNTuple", "ntuple.root"); 0402 /// 0403 /// // We want to show the page size distributions of columns with type `kSplitReal32` and `kSplitReal64`. 0404 /// auto hist = inspector->GetPageSizeDistribution( 0405 /// {ROOT::Experimental::EColumnType::kSplitReal32, 0406 /// ROOT::Experimental::EColumnType::kSplitReal64}); 0407 /// // The "PLC" option automatically sets the line color for each histogram in the `THStack`. 0408 /// // The "NOSTACK" option will draw the histograms on top of each other instead of stacked. 0409 /// hist->DrawClone("PLC NOSTACK"); 0410 /// canvas->BuildLegend(0.7, 0.8, 0.89, 0.89); 0411 /// canvas->DrawClone(); 0412 /// ~~~ 0413 std::unique_ptr<THStack> GetPageSizeDistribution(std::initializer_list<EColumnType> colTypes = {}, 0414 std::string histName = "", std::string histTitle = "", 0415 size_t nBins = 64); 0416 0417 ///////////////////////////////////////////////////////////////////////////// 0418 /// \brief Get storage information for a given (sub)field by ID. 0419 /// 0420 /// \param[in] fieldId The ID of the (sub)field for which to get the information. 0421 /// 0422 /// \return The storage information inspector for the provided (sub)field tree. 0423 const RFieldTreeInspector &GetFieldTreeInspector(DescriptorId_t fieldId) const; 0424 0425 ///////////////////////////////////////////////////////////////////////////// 0426 /// \brief Get a storage information inspector for a given (sub)field by name, including its subfields. 0427 /// 0428 /// \param[in] fieldName The name of the (sub)field for which to get the information. 0429 /// 0430 /// \return The storage information inspector for the provided (sub)field tree. 0431 const RFieldTreeInspector &GetFieldTreeInspector(std::string_view fieldName) const; 0432 0433 ///////////////////////////////////////////////////////////////////////////// 0434 /// \brief Get the number of fields of a given type or class present in the RNTuple. 0435 /// 0436 /// \param[in] typeNamePattern The type or class name to count. May contain regular expression patterns for grouping 0437 /// multiple kinds of types or classes. 0438 /// \param[in] searchInSubFields If set to `false`, only top-level fields will be considered. 0439 /// 0440 /// \return The number of fields that matches the provided type. 0441 size_t GetFieldCountByType(const std::regex &typeNamePattern, bool searchInSubFields = true) const; 0442 0443 ///////////////////////////////////////////////////////////////////////////// 0444 /// \brief Get the number of fields of a given type or class present in the RNTuple. 0445 /// 0446 /// \see GetFieldCountByType(const std::regex &typeNamePattern, bool searchInSubFields) const 0447 size_t GetFieldCountByType(std::string_view typeNamePattern, bool searchInSubFields = true) const 0448 { 0449 return GetFieldCountByType(std::regex{std::string(typeNamePattern)}, searchInSubFields); 0450 } 0451 0452 ///////////////////////////////////////////////////////////////////////////// 0453 /// \brief Get the IDs of (sub-)fields whose name matches the given string. 0454 /// 0455 /// \param[in] fieldNamePattern The name of the field name to get. Because field names are unique by design, 0456 /// providing a single field name will return a vector containing just the ID of that field. However, regular 0457 /// expression patterns are supported in order to get the IDs of all fields whose name follow a certain structure. 0458 /// \param[in] searchInSubFields If set to `false`, only top-level fields will be considered. 0459 /// 0460 /// \return A vector containing the IDs of fields that match the provided name. 0461 const std::vector<DescriptorId_t> 0462 GetFieldsByName(const std::regex &fieldNamePattern, bool searchInSubFields = true) const; 0463 0464 ///////////////////////////////////////////////////////////////////////////// 0465 /// \brief Get the IDs of (sub-)fields whose name matches the given string. 0466 /// 0467 /// \see GetFieldsByName(const std::regex &fieldNamePattern, bool searchInSubFields) const 0468 const std::vector<DescriptorId_t> GetFieldsByName(std::string_view fieldNamePattern, bool searchInSubFields = true) 0469 { 0470 return GetFieldsByName(std::regex{std::string(fieldNamePattern)}, searchInSubFields); 0471 } 0472 }; 0473 } // namespace Experimental 0474 } // namespace ROOT 0475 0476 #endif // ROOT7_RNTupleInspector
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