File Format Limitations
The following restrictions apply to MDF-file operations.
mdfVisualizesupports only integer and floating point data types in MDF-file channels.
The following MDF-file functions do not support the full range of international characters that are supported by the other MDF functions:
mdfCreatedoes not support adding custom file metadata fields.
mdfInfodoes not return custom file metadata fields.
mdfReadis restricted in the following ways:
mdfReaddoes not support array channels with more than 3 dimensions.
Reading from a nested composition of channels is not supported. You can read from simple structure channels or array channels, but not from a structure or array of composed signals.
mdfReadignores invalidation bits, so there is no indication of invalid samples and no errors or warnings.
mdfReadsimply reads in the data value as stored at the record position in the MDF file.
mdfReaddoes not support reading from channels with partial conversion rules.
mdfWriteis restricted in the following ways:
Boolean is not a supported data type in the MDF standard, so
mdfWritedoes not support the
logicaldata type. To work around this limitation, convert the
logicalvariable to an
uint8data type before writing to the MDF-file.
mdfWritefunction does not support writing array channels or structure channels.
When overwriting an existing channel, use a timetable that was created by the
mdfReadfunction with the option
IncludeMetadata=true. Do not remove any timetable custom properties returned by the
When overwriting an existing channel, the
ChannelReadOptionproperty in the timetable custom properties is used internally to keep track of the kind of conversion rule applied during the read. Do not modify this custom property in the timetable.
When writing a new channel to an MDF-file, the
mdfWritefunction does not support writing data with conversion rules. Only raw values can be written to new channels.
mdfFinalizemight be unable to write to a new or existing MDF-file at a remote URL location from MATLAB® Online™ or Linux®. To work around this limitation, first write the finalized file to MATLAB Drive™ (from MATLAB Online) or to a local folder (from Linux), and then move the finalized MDF-file to the necessary location.
When using CDFX-files, the following limitations apply:
SW-AXIS-CONTelements with the category
RES_AXISmust use the
SW-INSTANCE-REFelement, and the axis must be defined in a separate instance.
Instances with the category
CUBE_5that represent multidimensional arrays must use the
VGelement to group the physical values.
Although Vector BLF-files support many networks, Vehicle Network Toolbox™ support of BLF-files is limited to only CAN and CAN FD on Windows® and Linux operating systems.