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cdflib

Interact directly with CDF library

Description

MATLAB®provides direct access to dozens of functions in the CDF library. Using these functions, you can read and write data, create variables, attributes, and entries, and take advantage of other features of the CDF library. To use these functions, you must be familiar with the CDF C interface. Documentation about CDF is available at theCDF website.

The MATLAB functions correspond to functions in the CDF library new Standard Interface. In most cases, the syntax of a MATLAB function is similar to the syntax of the corresponding CDF library function. To use these functions, you must prefix the function name with the package name,cdflib. For example, to use the CDF library function to open an existing CDF file, use this syntax:

cdfid = cdflib.open('example.cdf');

MATLAB supports CDF version 3.7.0. For copyright information, see thecdfcopyright.txtfile.

The following tables list all of the functions in the MATLAB CDF library package, grouped by category.

Library Information

cdflib.getConstantNames Names of Common Data Format (CDF) library constants
cdflib.getConstantValue Numeric value corresponding to Common Data Format (CDF) library constant
cdflib.getFileBackward Return current backward compatibility mode setting
cdflib.getLibraryCopyright Copyright notice of Common Data Format (CDF) library
cdflib.getLibraryVersion Library version and release information
cdflib.getValidate Library validation mode
cdflib.setFileBackward Set backward compatibility mode
cdflib.setValidate Specify library validation mode

File Operations

cdflib.close Close Common Data Format (CDF) file
cdflib.create Create Common Data Format (CDF) file
cdflib.delete Delete existing Common Data Format (CDF) file
cdflib.getCacheSize Number of cache buffers used
cdflib.getChecksum Checksum mode
cdflib.getCompression Compression settings
cdflib.getCompressionCacheSize Number of compression cache buffers
cdflib.getCopyright Copyright notice in Common Data Format (CDF) file
cdflib.getFormat Format of Common Data Format (CDF) file
cdflib.getMajority Majority of variables
cdflib.getName Name of Common Data Format (CDF) file
cdflib.getReadOnlyMode Read-only mode
cdflib.getStageCacheSize Number of cache buffers for staging
cdflib.getVersion Common Data Format (CDF) library version and release information
cdflib.inquire Basic characteristics of Common Data Format (CDF) file
cdflib.open Open existing Common Data Format (CDF) file
cdflib.setCacheSize Specify number of dotCDF cache buffers
cdflib.setChecksum Specify checksum mode
cdflib.setCompression Specify compression settings
cdflib.setCompressionCacheSize Specify number of compression cache buffers
cdflib.setFormat Specify format of Common Data Format (CDF) file
cdflib.setMajority Specify majority of variables
cdflib.setReadOnlyMode Specify read-only mode
cdflib.setStageCacheSize Specify number of staging cache buffers for Common Data Format (CDF) file

Variables

cdflib.SetVarReservePercent Specify reserve percentage for variable
cdflib.closeVar Close specified variable from multifile format Common Data Format (CDF) file
cdflib.createVar Create new variable
cdflib.deleteVar Delete variable
cdflib.deleteVarRecords Delete range of records from variable
cdflib.getVarAllocRecords Number of records allocated for variable
cdflib.getVarBlockingFactor Blocking factor for variable
cdflib.getVarCacheSize Number of multifile cache buffers
cdflib.getVarCompression Information about compression used by variable
cdflib.getVarData 单值变量的记录
cdflib.getVarMaxAllocRecNum Maximum allocated record number for variable
cdflib.getVarMaxWrittenRecNum Maximum written record number for variable
cdflib.getVarName Variable name, given variable number
cdflib.getVarNum Variable number, given variable name
cdflib.getVarNumRecsWritten Number of records written to variable
cdflib.getVarPadValue Pad value for variable
cdflib.getVarRecordData Entire record for variable
cdflib.getVarReservePercent Compression reserve percentage for variable
cdflib.getVarSparseRecords Information about how variable handles sparse records
cdflib.getVarsMaxWrittenRecNum Maximum written record number for CDF file
cdflib.hyperGetVarData Read hyperslab of data from variable
cdflib.hyperPutVarData Write hyperslab of data to variable
cdflib.inquireVar Information about variable
cdflib.putVarData Write single value to variable
cdflib.putVarRecordData Write entire record to variable
cdflib.renameVar Rename existing variable
cdflib.setVarAllocBlockRecords Specify range of records to be allocated for variable
cdflib.setVarBlockingFactor Specify blocking factor for variable
cdflib.setVarCacheSize Specify number of multi-file cache buffers for variable
cdflib.setVarCompression Specify compression settings used with variable
cdflib.setVarInitialRecs 指定initial number of records written to variable
cdflib.setVarPadValue Specify pad value used with variable
cdflib.setVarSparseRecords Specify how variable handles sparse records
cdflib.setVarsCacheSize Specify number of cache buffers used for all variables

Attributes

cdflib.createAttr Create attribute
cdflib.deleteAttr Delete attribute
cdflib.deleteAttrEntry Delete attribute entry
cdflib.deleteAttrgEntry Delete entry in global attribute
cdflib.getAttrEntry Value of entry in attribute with variable scope
cdflib.getAttrMaxEntry Number of last entry for variable attribute
cdflib.getAttrMaxgEntry Number of last entry for global attribute
cdflib.getAttrName Name of attribute, given attribute number
cdflib.getAttrNum Attribute number, given attribute name
cdflib.getAttrScope Scope of attribute
cdflib.getAttrgEntry Value of entry in global attribute
cdflib.getNumAttrEntries Number of entries for attribute with variable scope
cdflib.getNumAttrgEntries Number of entries for attribute with global scope
cdflib.getNumAttributes Number of attributes with variable scope
cdflib.getNumgAttributes Number of attributes with global scope
cdflib.inquireAttr Information about attribute
cdflib.inquireAttrEntry Information about entry in attribute with variable scope
cdflib.inquireAttrgEntry Information about entry in attribute with global scope
cdflib.putAttrEntry Write value to entry in attribute with variable scope
cdflib.putAttrgEntry Write value to entry in attribute with global scope
cdflib.renameAttr Rename existing attribute

效用函数

cdflib.computeEpoch Convert time value toCDF_EPOCHvalue
cdflib.computeEpoch16 Convert time value toCDF_EPOCH16value
cdflib.epoch16Breakdown ConvertCDF_EPOCH16value to time value
cdflib.epochBreakdown ConvertCDF_EPOCHvalue into time value

Limitations

  • CDF files do not support non-ASCII encoded inputs. Variable names, attributes names, variable values, and attribute values must have 7-bit ASCII encoding. Attempting to write non-ASCII encoded inputs results in an error or data with corrupted characters.

  • The MATLAB CDF library package does not support the data typesCDF_TIME_TT2000andCDF_INT8.