mdfCreate

Create MDF file with metadata

Since R2022a

Syntax

mdfCreate(mdfFileName)

mdfCreate(mdfFileName,FileInfo=mdfInfoObj)

newMDFFile = mdfCreate(___)

Description

mdfCreate(mdfFileName) creates an MDF file at the location specified by mdfFileName, using default file metadata. The file name must include the extension .dat, .mdf, or .mf4. mdfFileName can specify an absolute or full path, or a URL for a file on a remote server.

mdfCreate(mdfFileName,FileInfo=mdfInfoObj) creates an MDF file using the specified metadata to configure during file creation. The object mdfInfoObj must be of the form returned by the mdfInfo function, which you can use to create the object and then modify it as needed. The supported values for the mdfInfoObj.Version property are "3.00", "3.10", "3.20", "3.30", "4.00", "4.10", and "4.20".

newMDFFile = mdfCreate(___) creates an MDF file and returns its full path name as a string to the variable newMDFFile. The returned full path can be useful when specifying a partial or relative path to create the file.

Examples

Create an MDF File with Default Metadata

Create a new MDF file, and view its metadata.

mdfCreate("MDF_25Dec.mf4")

ans = 

    "C:\data\mdf\MDF_25Dec.mf4"

mdfInfo("MDF_25Dec.mf4")

ans = 

  MDFInfo with properties:

   File Details
                  Name: "MDF_25Dec.mf4"
                  Path: "C:\data\mdf\MDF_25Dec.mf4"
                Author: ""
            Department: ""
               Project: ""
               Subject: ""
               Comment: ""
               Version: "4.20"
      InitialTimestamp: 2022-10-20 18:39:41.000000000

   Creator Details
     ProgramIdentifier: "MATLAB"
     CreatorVendorName: "The MathWorks, Inc."
       CreatorToolName: "MATLAB"
    CreatorToolVersion: "9.14.0.2081372 (R2023a)"
       CreatorUserName: ""
        CreatorComment: ""

   File Contents
            Attachment: [0×8 table]
     ChannelGroupCount: 0

Create an MDF File with Custom Metadata

Create a new MDF file with modified metadata.

Create a default information object, set its properties, and make a new MDF file.

minfo = mdfInfo;
minfo.Comment = "25-Dec Shift B.";
minfo.Version = "4.10";
%   ⋮
% Modify other properites as needed.
%   ⋮
mdfCreate("MyMDFfile.mf4",FileInfo=minfo);

Create a new MDF file with metadata taken from an existing file.

minfo = mdfInfo("MyMDFfile1.mf4");  % Existing MDF file.
info.Version = "4.10";
createdFilePath = mdfCreate("MyMDFfile2.mf4", FileInfo=info) % New file, with matadata from existing file.

Input Arguments

mdfFileName — MDF file name

string | char

MDF file name to create, specified as a string or character vector. The file name can be a relative or absolute path. The name must include the extension .dat, .mdf, or .mf4.

Depending on the location you are accessing, mdfFileName can take one of these forms.

Location	Form
Current folder or MATLAB® path	To access a file in the current folder or MATLAB path, specify the name of the file in filename, including the file extension. Example: "myMdfFile.mf4"
Other folders	To access a file in a folder other than the current folder, specify the full or relative path name in filename. Example: "C:\myFolder\myMdfFile.mf4" Example: "\dataDir\myMdfFile.mf4"
Remote locations	To access a file in a remote location, filename must contain the full path of the file specified as a uniform resource locator (URL) of the form: scheme://path_to_file/myMdfFile.mf4 Based on the remote location, scheme can be one of the values in this table. Remote Location scheme Amazon S3™ s3 Windows Azure® Blob Storage wasb, wasbs HDFS™ hdfs For more information, see Work with Remote Data. Example: "s3://bucketname/path_to_file/myMdfFile.mf4"

Example: "MDF_25Dec.mf4"

Data Types: char | string

Output Arguments

newMDFFile — Name of newly created MDF file

string

Full path name of the newly created MDF file, returned as a string.

Limitations

• mdfCreate does not support adding custom file metadata fields.

Version History

Introduced in R2022a

R2023a: mdfCreate Accepts Object Argument

In previous releases, mdfCreate accepted a structure input argument. Starting in R2023a, the input argument is an MDFInfo object. This update is consistent with the update to the mdfInfo function, which creates an object you can use as input to mdfCreate. Where possible, the properties of this object reflect the field names of the old structure, so programmatic access might be unchanged.

R2023a: Support for Remote File URLs

You can directly access MDF file data stored at remote locations, including Amazon S3, Azure^® Blob Storage, and HDFS.