MDF 文件快速入门
此示例说明如何访问关于 MDF 文件及其内容的信息。
查看文件详细信息
通过指定文件名，使用 mdfInfo 查看 MDF 文件的元数据。此示例文件是使用 Vehicle Network Toolbox™ 从 MATLAB® 创建的。
fileInfo = mdfInfo("VehicleData.mf4")fileInfo =
MDFInfo with properties:
File Details
Name: "VehicleData.mf4"
Path: "/tmp/Bdoc25b_2988451_1428583/tpf364ba40/vnt-ex51113426/VehicleData.mf4"
Author: "Engineer"
Department: "Automotive"
Project: "Demo"
Subject: "Prototype"
Comment: "Example file"
Version: "4.20"
InitialTimestamp: 2024-11-14 19:16:35.000000000
Creator Details
ProgramIdentifier: "MATLAB"
CreatorVendorName: "The MathWorks, Inc."
CreatorToolName: "MATLAB"
CreatorToolVersion: "25.1.0.2768609 (R2025a) Prerelease"
CreatorUserName: "engineer"
CreatorComment: "Created with Vehicle Network Toolbox"
File Contents
Attachment: [1×7 table]
ChannelGroupCount: 2
Event: [0×8 eventtable]
File Details 节中的属性提供了有关 MDF 文件的基本详细信息。
有关原始工具的信息可在 Creator Details 节中找到。
有关附件、通道组和事件的详细信息列在 File Contents 节中。
查看通道组详细信息
MDF 文件中的数据组织到通道组内的各通道中。此示例文件包含两个通道组，由 ChannelGroupCount 属性指示。
fileInfo.ChannelGroupCount
ans = uint64
2
使用 mdfChannelGroupInfo 查看有关两个通道组的详细信息。
chanGrpInfo = mdfChannelGroupInfo("VehicleData.mf4")chanGrpInfo=2×13 table
GroupNumber AcquisitionName Comment NumSamples DataSize Sorted SourceName SourcePath SourceComment SourceType SourceBusType SourceBusChannelNumber SourceSimulated
___________ _______________ ___________________________________________________________________________ __________ ________ ______ ___________ ___________ _____________ ___________ _____________ ______________________ _______________
1 <undefined> Simulation of an automatic transmission controller during passing maneuver. 751 43558 true <undefined> <undefined> <undefined> Unspecified Unspecified 0 false
2 <undefined> Simulation of engine gas dynamics. 92033 2208792 true <undefined> <undefined> <undefined> Unspecified Unspecified 0 false
查看通道详细信息
使用 mdfChannelInfo 查看此 MDF 文件中所有通道的详细信息。
chanInfoDefault = mdfChannelInfo("VehicleData.mf4")chanInfoDefault=12×13 table
Name GroupNumber GroupNumSamples GroupAcquisitionName GroupComment GroupSourceName GroupSourcePath DisplayName Unit Comment ExtendedNamePrefix SourceName SourcePath
_________________ ___________ _______________ ____________________ ___________________________________________________________________________ _______________ _______________ ___________ ___________ ___________ __________________ ___________ ___________
"AirFlow" 2 92033 <undefined> Simulation of engine gas dynamics. <undefined> <undefined> "" g/s <undefined> <undefined> <undefined> <undefined>
"Brake" 1 751 <undefined> Simulation of an automatic transmission controller during passing maneuver. <undefined> <undefined> "" ft*lbf <undefined> <undefined> <undefined> <undefined>
"EngineRPM" 1 751 <undefined> Simulation of an automatic transmission controller during passing maneuver. <undefined> <undefined> "" rpm <undefined> <undefined> <undefined> <undefined>
"FuelRate" 2 92033 <undefined> Simulation of engine gas dynamics. <undefined> <undefined> "" g/s <undefined> <undefined> <undefined> <undefined>
"Gear" 1 751 <undefined> Simulation of an automatic transmission controller during passing maneuver. <undefined> <undefined> "" <undefined> <undefined> <undefined> <undefined> <undefined>
"ImpellerTorque" 1 751 <undefined> Simulation of an automatic transmission controller during passing maneuver. <undefined> <undefined> "" ft*lbf <undefined> <undefined> <undefined> <undefined>
"OutputTorque" 1 751 <undefined> Simulation of an automatic transmission controller during passing maneuver. <undefined> <undefined> "" ft*lbf <undefined> <undefined> <undefined> <undefined>
"Throttle" 1 751 <undefined> Simulation of an automatic transmission controller during passing maneuver. <undefined> <undefined> "" % <undefined> <undefined> <undefined> <undefined>
"TransmissionRPM" 1 751 <undefined> Simulation of an automatic transmission controller during passing maneuver. <undefined> <undefined> "" rpm <undefined> <undefined> <undefined> <undefined>
"VehicleSpeed" 1 751 <undefined> Simulation of an automatic transmission controller during passing maneuver. <undefined> <undefined> "" mph <undefined> <undefined> <undefined> <undefined>
"time" 1 751 <undefined> Simulation of an automatic transmission controller during passing maneuver. <undefined> <undefined> "" s <undefined> <undefined> <undefined> <undefined>
"time" 2 92033 <undefined> Simulation of engine gas dynamics. <undefined> <undefined> "" s <undefined> <undefined> <undefined> <undefined>
默认情况下，该函数返回最少的通道元数据。要查看其他元数据，请将 AdditionalMetadata 选项设置为 true。
chanInfoAdditional = mdfChannelInfo("VehicleData.mf4", AdditionalMetadata=true)chanInfoAdditional=12×25 table
Name GroupNumber GroupNumSamples GroupAcquisitionName GroupComment GroupSourceName GroupSourcePath DisplayName Unit Comment ExtendedNamePrefix SourceName SourcePath Type SyncType DataType NumBits ComponentType CompositionType ConversionType SourceComment SourceType SourceBusType SourceBusChannelNumber SourceSimulated
_________________ ___________ _______________ ____________________ ___________________________________________________________________________ _______________ _______________ ___________ ___________ ___________ __________________ ___________ ___________ ___________ ________ ___________________________ _______ _____________ _______________ ______________ _____________ ___________ _____________ ______________________ _______________
"AirFlow" 2 92033 <undefined> Simulation of engine gas dynamics. <undefined> <undefined> "" g/s <undefined> <undefined> <undefined> <undefined> FixedLength None RealLittleEndian 64 None None Unspecified "" Unspecified Unspecified 0 false
"Brake" 1 751 <undefined> Simulation of an automatic transmission controller during passing maneuver. <undefined> <undefined> "" ft*lbf <undefined> <undefined> <undefined> <undefined> FixedLength None IntegerUnsignedLittleEndian 8 None None Unspecified "" Unspecified Unspecified 0 false
"EngineRPM" 1 751 <undefined> Simulation of an automatic transmission controller during passing maneuver. <undefined> <undefined> "" rpm <undefined> <undefined> <undefined> <undefined> FixedLength None RealLittleEndian 64 None None Unspecified "" Unspecified Unspecified 0 false
"FuelRate" 2 92033 <undefined> Simulation of engine gas dynamics. <undefined> <undefined> "" g/s <undefined> <undefined> <undefined> <undefined> FixedLength None RealLittleEndian 64 None None Unspecified "" Unspecified Unspecified 0 false
"Gear" 1 751 <undefined> Simulation of an automatic transmission controller during passing maneuver. <undefined> <undefined> "" <undefined> <undefined> <undefined> <undefined> <undefined> FixedLength None IntegerUnsignedLittleEndian 8 None None Unspecified "" Unspecified Unspecified 0 false
"ImpellerTorque" 1 751 <undefined> Simulation of an automatic transmission controller during passing maneuver. <undefined> <undefined> "" ft*lbf <undefined> <undefined> <undefined> <undefined> FixedLength None RealLittleEndian 64 None None Unspecified "" Unspecified Unspecified 0 false
"OutputTorque" 1 751 <undefined> Simulation of an automatic transmission controller during passing maneuver. <undefined> <undefined> "" ft*lbf <undefined> <undefined> <undefined> <undefined> FixedLength None RealLittleEndian 64 None None Unspecified "" Unspecified Unspecified 0 false
"Throttle" 1 751 <undefined> Simulation of an automatic transmission controller during passing maneuver. <undefined> <undefined> "" % <undefined> <undefined> <undefined> <undefined> FixedLength None RealLittleEndian 64 None None Unspecified "" Unspecified Unspecified 0 false
"TransmissionRPM" 1 751 <undefined> Simulation of an automatic transmission controller during passing maneuver. <undefined> <undefined> "" rpm <undefined> <undefined> <undefined> <undefined> FixedLength None RealLittleEndian 64 None None Unspecified "" Unspecified Unspecified 0 false
"VehicleSpeed" 1 751 <undefined> Simulation of an automatic transmission controller during passing maneuver. <undefined> <undefined> "" mph <undefined> <undefined> <undefined> <undefined> FixedLength None RealLittleEndian 64 None None Unspecified "" Unspecified Unspecified 0 false
"time" 1 751 <undefined> Simulation of an automatic transmission controller during passing maneuver. <undefined> <undefined> "" s <undefined> <undefined> <undefined> <undefined> Master Time RealLittleEndian 64 None None Unspecified "" Unspecified Unspecified 0 false
"time" 2 92033 <undefined> Simulation of engine gas dynamics. <undefined> <undefined> "" s <undefined> <undefined> <undefined> <undefined> Master Time RealLittleEndian 64 None None Unspecified "" Unspecified Unspecified 0 false
在 MDF 文件中查找通道
mdfChannelInfo 也可以查询 MDF 文件中的通道详细信息，前提是该名称是全部或部分已知的。该函数提供的选项 Channel 支持使用通配符查找字符串匹配项。
要查找名称正好为 Gear 的通道，请使用以下代码：
pwmChanInfoExact = mdfChannelInfo("VehicleData.mf4", Channel="Gear")
pwmChanInfoExact=1×13 table
Name GroupNumber GroupNumSamples GroupAcquisitionName GroupComment GroupSourceName GroupSourcePath DisplayName Unit Comment ExtendedNamePrefix SourceName SourcePath
______ ___________ _______________ ____________________ ___________________________________________________________________________ _______________ _______________ ___________ ___________ ___________ __________________ ___________ ___________
"Gear" 1 751 <undefined> Simulation of an automatic transmission controller during passing maneuver. <undefined> <undefined> "" <undefined> <undefined> <undefined> <undefined> <undefined>
要查找名称包含子字符串 RPM 的通道，请使用以下代码：
pwmChanInfoWildcards = mdfChannelInfo("VehicleData.mf4", Channel="*RPM*")
pwmChanInfoWildcards=2×13 table
Name GroupNumber GroupNumSamples GroupAcquisitionName GroupComment GroupSourceName GroupSourcePath DisplayName Unit Comment ExtendedNamePrefix SourceName SourcePath
_________________ ___________ _______________ ____________________ ___________________________________________________________________________ _______________ _______________ ___________ ____ ___________ __________________ ___________ ___________
"EngineRPM" 1 751 <undefined> Simulation of an automatic transmission controller during passing maneuver. <undefined> <undefined> "" rpm <undefined> <undefined> <undefined> <undefined>
"TransmissionRPM" 1 751 <undefined> Simulation of an automatic transmission controller during passing maneuver. <undefined> <undefined> "" rpm <undefined> <undefined> <undefined> <undefined>
