MATLAB读取tdms文件函数包.zip

function metaStruct = TDMS_preprocessFile(fid,tdmsFileName,params) %TDMS_preprocessFile Populates props and gets segment information % % NOTE: This file shouldn't be called directly by the user % % metaStruct = TDMS_preprocessFile(fid,tdmsFileName,params) % % INPUTS % ======================================================================= % fid : file id of opened tdms file, may be null if INDEX_DEBUG is true % tdmsFileName : full path to tdms file OR tdms index file for INDEX_DEBUG % params : all optional inputs from TDMS_readTDMSFile % % OUTPUTS % ======================================================================= % metaStruct : % structure with fields: % % The following 3 variables are all the same length, and have one index % for each unique object. Each object may be one of the following types, % file root, group object, or channel object. Only channel objects may % have data. % % rawDataInfo : (structure array) % NOTE: This holds the most recent info for an object, and can be % changed on a per segment basis, segInfo is used to hold % information that is needed per segement % % .lengthOfIndex - length of raw data index (not used) % .dataType - enumerated dataType (Labview) % .dimensionData - currently ignored (should be 1d) % .numberOfValues - # of values to read each time % .totalSizeBytes - # of bytes per values % .numberProperties - # of properties defined for the object % .infoSet - a logical on whether or not this data has % been set (for error checking) % .propNames - a cell array for definining property names % .propValues - cell array for holding property values % % numberDataPoints : an array which specifies the # of data points for % each object (used for preallocation) % objectNameList : (cell array of strings) names of all objects in the % TDMS file % % Info for each segment ... % % segInfo : (struct array) % .rawPos - position of raw data for that segment % .kTocNewObjList - flag on whether a new channel list was % created or not % .objOrder - array specifying indices of the objects to assign % data to, order specifies read order, and values % are indexed % into the objectNameList & rawDataInfo struct % .nRawObjects - length of objOrder % .nSamplesRead - array, # of samples to read for each object % .isInterleaved - logical, whether that segment uses interleaved % data or not % .isBigEndian - logical % .nChunks - # of times to read data using the parameters % above before moving onto the next segment % % See also: TDMS_processLeadIn, TDMS_getDataSize, TDMS_getPropValue %PARAMETERS - passed in from TDMS_readTDMSFile %========================================================================== UTC_DIFF = params.UTC_DIFF; MAX_NUM_OBJECTS = params.MAX_NUM_OBJECTS; MAX_NUM_PROPS = params.MAX_NUM_PROPS; N_SEGS_GUESS = params.N_SEGS_GUESS; N_SEGS_INC = params.N_SEGS_INC; DEBUG = params.DEBUG; DATE_STR_FORMAT = params.DATE_STR_FORMAT; UNICODE_FORMAT = params.STRING_ENCODING; USE_INDEX = params.USE_INDEX; INIT_CHUNK_SIZE = params.INIT_CHUNK_SIZE; TDMS_INDEX_EXT = params.TDMS_INDEX_EXT; MACHINE_FORMAT = params.MACHINE_FORMAT; STRING_ENCODING = params.STRING_ENCODING; CURRENT_VERSION = params.CURRENT_VERSION; INDEX_DEBUG = params.INDEX_DEBUG; %DONT CHANGE THESE %========================================================================== LEAD_IN_LENGTH = 28; %# of bytes of lead in %FIGURING OUT WHICH FILE TO READ %========================================================================== [tdmsPathToFile,tdmsNameOnly] = fileparts(tdmsFileName); if isempty(params.META_STRUCT) isIndexFID = false; if USE_INDEX || INDEX_DEBUG if INDEX_DEBUG indexFile = tdmsFileName; else indexFile = fullfile(tdmsPathToFile,[tdmsNameOnly TDMS_INDEX_EXT]); end if exist(indexFile,'file') fid = fopen(indexFile,'r',MACHINE_FORMAT,STRING_ENCODING); isIndexFID = true; else %Just use the tdms file, which we have already tested to exist if INDEX_DEBUG %NOTE: With INDEX_DEBUG we explicitly passed in the index %file to read and parse (generally for debugging purposes %so if it doesn't exist, then we have a problem error('Specified tdms_index file doesn not exist') end end end else %Quits early if meta struct input is valid %====================================================================== metaStruct = params.META_STRUCT; if ~isstruct(metaStruct) || ~isfield(metaStruct,'version') || ~isfield(metaStruct,'fileName') error('The META_STRUCT parameter passed should be a structure with fields "version" and "fileName"') end if metaStruct.version ~= CURRENT_VERSION error('Mismatch in version creation, version of struct %d, please run with latest version: %d') end if ~strcmpi(metaStruct.fileName,tdmsNameOnly) fprintf('Filename from metaStruct: %s\n',metaStruct.fileName); fprintf('Filename from input: %s\n',tdmsNameOnly); error('Mismatch in filenames, see printout above') end return end if isIndexFID lastLetter = double('h'); %used for .tdms_index files else lastLetter = double('m'); %used for .tdms files end %INITIALIZE OUTPUTS %========================================================================== curNumTotalObjects = 0; %Current # of objects numberDataPoints = zeros(1,MAX_NUM_OBJECTS); objectNameList = cell(1,MAX_NUM_OBJECTS); %names of all objects rawDataInfo = initRawInfoStruct(MAX_NUM_PROPS,MAX_NUM_OBJECTS); segInfo = initSegStruct(N_SEGS_GUESS); %========================================================================== %TEMP VARIABLES %========================================================================== objectHasRawData = false(1,MAX_NUM_OBJECTS); %This is needed for adding %# of data points together ranOnce = false; nSegs = 0; %Get eof & return to start fseek(fid,0,1); eofPosition = ftell(fid); fseek(fid,0,-1); %START OF READING %========================================================================== curPosCounter = 0; %Used to keep track of where in the actual tdms file we %would be at various points, this is used for parsing verification as well %as assisting with more complicated reads while ftell(fid) ~= eofPosition nSegs = nSegs + 1; if nSegs > length(segInfo) segInfo = [segInfo initSegStruct(N_SEGS_INC)]; %#ok<AGROW> end if DEBUG disp('------ START OF DEBUG -------') fprintf(2,'CURRENT SEGMENT: %d\n',nSegs); fprintf(2,'Current file position: %d\n',curPosCounter); end %LEAD IN HANDLING %====================================================================== [flags,info,eof_error] = TDMS_processLeadIn(fid,lastLetter); if eof_error %This should only happen once at the end fprintf(2,['WARNING: File was not closed properly.\n' ... 'Data will most likely be missing at the end of the file\n']); nSegs = nSegs - 1; break end curPosCounter = curPosCounter + LEAD_IN_LENGTH + info.segLength; segInfo(nSegs).rawPos = curPosCounter -