asammdf 2.8.2

ASAM MDF measurement data file parser

asammdf is a fast parser/editor for ASAM (Associtation for Standardisation of Automation and Measuring Systems) MDF (Measurement Data Format) files.

asammdf supports MDF versions 2 (.dat), 3 (.mdf) and 4 (.mf4).

asammdf works on Python 2.7, and Python >= 3.4 (Travis CI tests done with Python 2.7 and Python >= 3.5)

Project goals

The main goals for this library are:

• to be faster than the other Python based mdf libraries

• to have clean and easy to understand code base

• to have minimal 3-rd party dependencies

Features

• create new mdf files from scratch

• append new channels

• read unsorted MDF v3 and v4 files

• filter a subset of channels from original mdf file

• cut measurement to specified time interval

• convert to different mdf version

• export to Excel, HDF5, Matlab and CSV

• merge multiple files sharing the same internal structure

• read and save mdf version 4.10 files containing zipped data blocks

• split large data blocks (configurable size) for mdf version 4

• disk space savings by compacting 1-dimensional integer channels (configurable)

• full support (read, append, save) for the following map types (multidimensional array channels):

  • mdf version 3 channels with CDBLOCK

  • mdf version 4 structure channel composition

  • mdf version 4 channel arrays with CNTemplate storage and one of the array types:

    • 0 - array

    • 1 - scaling axis

    • 2 - look-up

• add and extract attachments for mdf version 4

• files are loaded in RAM for fast operations

• handle large files (exceeding the available RAM) using memory = minimum argument

• extract channel data, master channel and extra channel information as Signal objects for unified operations with v3 and v4 files

• time domain operation using the Signal class

  • Pandas data frames are good if all the channels have the same time based

  • usually a measurement will have channels from different sources at different rates

  • the Signal class facilitates operations with such channels

Major features not implemented (yet)

• for version 3

  • functionality related to sample reduction block (but the class is defined)

• for version 4

  • handling of bus logging measurements

  • handling of unfinished measurements (mdf 4)

  • full support for remaining mdf 4 channel arrays types

  • xml schema for TXBLOCK and MDBLOCK

  • partial conversions

  • event blocks

  • channels with default X axis

  • chanenls with reference to attachment

Usage

from asammdf import MDF

mdf = MDF('sample.mdf')
speed = mdf.get('WheelSpeed')
speed.plot()

important_signals = ['WheelSpeed', 'VehicleSpeed', 'VehicleAcceleration']
# get short measurement with a subset of channels from 10s to 12s
short = mdf.filter(important_signals).cut(start=10, stop=12)

# convert to version 4.10 and save to disk
short.convert('4.10').save('important signals.mf4')

# plot some channels from a huge file
efficient = MDF('huge.mf4', memory='minimum')
for signal in efficient.select(['Sensor1', 'Voltage3']):
    signal.plot()

Check the examples folder for extended usage demo, or the documentation http://asammdf.readthedocs.io/en/master/examples.html

Documentation

http://asammdf.readthedocs.io/en/master

Installation

asammdf is available on

• github: https://github.com/danielhrisca/asammdf/

• PyPI: https://pypi.org/project/asammdf/

Dependencies

asammdf uses the following libraries

• numpy : the heart that makes all tick

• numexpr : for algebraic and rational channel conversions

• matplotlib : for Signal plotting

• wheel : for installation in virtual environments

• pandas : for DataFrame export

optional dependencies needed for exports

• h5py : for HDF5 export

• xlsxwriter : for Excel export

• scipy : for Matlab .mat export

Benchmarks

Graphical results can be seen here at http://asammdf.readthedocs.io/en/master/benchmarks.html

Python 3 x86

Benchmark environment

• 3.6.3 (v3.6.3:2c5fed8, Oct 3 2017, 17:26:49) [MSC v.1900 32 bit (Intel)]

• Windows-10-10.0.16299-SP0

• Intel64 Family 6 Model 69 Stepping 1, GenuineIntel

• 16GB installed RAM

Notations used in the results

• full = asammdf MDF object created with memory=full (everything loaded into RAM)

• low = asammdf MDF object created with memory=low (raw channel data not loaded into RAM, but metadata loaded to RAM)

• minimum = asammdf MDF object created with memory=full (lowest possible RAM usage)

• compress = mdfreader mdf object created with compression=blosc

• noDataLoading = mdfreader mdf object read with noDataLoading=True

Files used for benchmark:

• 183 groups

• 36424 channels

Open file	Time [ms]	RAM [MB]
asammdf 2.8.1 full mdfv3	1207	260
asammdf 2.8.1 low mdfv3	1065	107
asammdf 2.8.1 minimum mdfv3	746	52
mdfreader 2.7.4 mdfv3	3061	392
mdfreader 2.7.4 noDataLoading mdfv3	1154	106
asammdf 2.8.1 full mdfv4	2811	298
asammdf 2.8.1 low mdfv4	2708	134
asammdf 2.8.1 minimum mdfv4	2081	58
mdfreader 2.7.4 mdfv4	7293	397
mdfreader 2.7.4 noDataLoading mdfv4	4557	109

Save file	Time [ms]	RAM [MB]
asammdf 2.8.1 full mdfv3	564	264
asammdf 2.8.1 low mdfv3	628	115
asammdf 2.8.1 minimum mdfv3	1780	58
mdfreader 2.7.4 mdfv3	9021	412
mdfreader 2.7.4 noDataLoading mdfv3	0*	0*
asammdf 2.8.1 full mdfv4	798	303
asammdf 2.8.1 low mdfv4	916	143
asammdf 2.8.1 minimum mdfv4	3992	67
mdfreader 2.7.4 mdfv4	8069	417
mdfreader 2.7.4 noDataLoading mdfv4	9646	434

Get all channels (36424 calls)	Time [ms]	RAM [MB]
asammdf 2.8.1 full mdfv3	1226	265
asammdf 2.8.1 low mdfv3	17517	117
asammdf 2.8.1 minimum mdfv3	19145	63
mdfreader 2.7.4 mdfv3	120	392
mdfreader 2.7.4 nodata mdfv3	30561	130
asammdf 2.8.1 full mdfv4	1234	304
asammdf 2.8.1 low mdfv4	20214	141
asammdf 2.8.1 minimum mdfv4	23583	65
mdfreader 2.7.4 mdfv4	115	397
mdfreader 2.7.4 nodata mdfv4	38428	123

Convert file	Time [ms]	RAM [MB]
asammdf 2.8.1 full v3 to v4	5507	638
asammdf 2.8.1 low v3 to v4	6345	215
asammdf 2.8.1 minimum v3 to v4	8098	118
asammdf 2.8.1 full v4 to v3	6761	635
asammdf 2.8.1 low v4 to v3	7732	194
asammdf 2.8.1 minimum v4 to v3	12232	94

Merge files	Time [ms]	RAM [MB]
asammdf 2.8.1 full v3	14283	1166
asammdf 2.8.1 low v3	15639	320
asammdf 2.8.1 minimum v3	18547	181
mdfreader 2.7.4 v3	16451	929
mdfreader 2.7.4 nodata v3	0*	0*
asammdf 2.8.1 full v4	20925	1223
asammdf 2.8.1 low v4	22659	352
asammdf 2.8.1 minimum v4	29923	166
mdfreader 2.7.4 v4	25032	919
mdfreader 2.7.4 nodata v4	24316	948

Python 3 x64

Benchmark environment

• 3.6.2 (v3.6.2:5fd33b5, Jul 8 2017, 04:57:36) [MSC v.1900 64 bit (AMD64)]

• Windows-10-10.0.16299-SP0

• Intel64 Family 6 Model 69 Stepping 1, GenuineIntel

• 16GB installed RAM

Notations used in the results

• full = asammdf MDF object created with memory=full (everything loaded into RAM)

• low = asammdf MDF object created with memory=low (raw channel data not loaded into RAM, but metadata loaded to RAM)

• minimum = asammdf MDF object created with memory=full (lowest possible RAM usage)

• compress = mdfreader mdf object created with compression=blosc

• noDataLoading = mdfreader mdf object read with noDataLoading=True

Files used for benchmark:

• 183 groups

• 36424 channels

Open file	Time [ms]	RAM [MB]
asammdf 2.8.1 full mdfv3	1054	317
asammdf 2.8.1 low mdfv3	919	164
asammdf 2.8.1 minimum mdfv3	592	76
mdfreader 2.7.4 mdfv3	2545	426
mdfreader 2.7.4 compress mdfv3	4188	126
mdfreader 2.7.4 noDataLoading mdfv3	1015	173
asammdf 2.8.1 full mdfv4	2438	380
asammdf 2.8.1 low mdfv4	2311	215
asammdf 2.8.1 minimum mdfv4	1649	87
mdfreader 2.7.4 mdfv4	6176	438
mdfreader 2.7.4 compress mdfv4	7940	137
mdfreader 2.7.4 noDataLoading mdfv4	4013	180

Save file	Time [ms]	RAM [MB]
asammdf 2.8.1 full mdfv3	507	319
asammdf 2.8.1 low mdfv3	515	171
asammdf 2.8.1 minimum mdfv3	1263	84
mdfreader 2.7.4 mdfv3	7590	454
mdfreader 2.7.4 noDataLoading mdfv3	0*	0*
mdfreader 2.7.4 compress mdfv3	7236	423
asammdf 2.8.1 full mdfv4	599	385
asammdf 2.8.1 low mdfv4	703	227
asammdf 2.8.1 minimum mdfv4	3157	97
mdfreader 2.7.4 mdfv4	6764	457
mdfreader 2.7.4 noDataLoading mdfv4	8053	476
mdfreader 2.7.4 compress mdfv4	6677	416

Get all channels (36424 calls)	Time [ms]	RAM [MB]
asammdf 2.8.1 full mdfv3	1016	323
asammdf 2.8.1 low mdfv3	5599	177
asammdf 2.8.1 minimum mdfv3	7105	91
mdfreader 2.7.4 mdfv3	102	426
mdfreader 2.7.4 nodata mdfv3	16651	208
mdfreader 2.7.4 compress mdfv3	515	126
asammdf 2.8.1 full mdfv4	1080	388
asammdf 2.8.1 low mdfv4	10658	225
asammdf 2.8.1 minimum mdfv4	13554	98
mdfreader 2.7.4 mdfv4	91	438
mdfreader 2.7.4 nodata mdfv4	26847	204
mdfreader 2.7.4 compress mdfv4	517	138

Convert file	Time [ms]	RAM [MB]
asammdf 2.8.1 full v3 to v4	4995	750
asammdf 2.8.1 low v3 to v4	5646	330
asammdf 2.8.1 minimum v3 to v4	6902	161
asammdf 2.8.1 full v4 to v3	5750	751
asammdf 2.8.1 low v4 to v3	6572	313
asammdf 2.8.1 minimum v4 to v3	10229	133

Merge files	Time [ms]	RAM [MB]
asammdf 2.8.1 full v3	12050	1311
asammdf 2.8.1 low v3	14122	454
asammdf 2.8.1 minimum v3	16537	227
mdfreader 2.7.4 v3	14710	974
mdfreader 2.7.4 compress v3	19571	982
asammdf 2.8.1 full v4	17569	1431
asammdf 2.8.1 low v4	19297	548
asammdf 2.8.1 minimum v4	25442	227
mdfreader 2.7.4 v4	22324	971
mdfreader 2.7.4 nodata v4	21581	1013
mdfreader 2.7.4 compress v4	26916	974