示例#1
0
    def test_resample(self):
        raster = 1.33
        sigs = [
            Signal(
                samples=np.arange(1000, dtype='f8'),
                timestamps=np.concatenate(
                    [np.arange(500), np.arange(1000, 1500)]),
                name=f'Signal_{i}',
            ) for i in range(20)
        ]

        mdf = MDF()
        mdf.append(sigs)
        mdf = mdf.resample(raster=raster)

        target_timestamps = np.arange(0, 1500, 1.33)
        target_samples = np.concatenate([
            np.arange(0, 500, 1.33),
            np.linspace(499.00215568862274, 499.9976646706587, 376),
            np.arange(500.1600000000001, 1000, 1.33)
        ])

        for i, sig in enumerate(mdf.iter_channels(skip_master=True)):
            self.assertTrue(np.array_equal(sig.timestamps, target_timestamps))
            self.assertTrue(np.allclose(sig.samples, target_samples))
def GetDatafromMdf_asDF(filename, SigList, SampleTime=0.01, EncodeEnums=True):
    ## Local helper
    def cleanEnumString(string):
        return string.decode().split(r'\x00')[0].strip().strip('\x00')

    ## Function body
    tempMDF = MDF()
    sigs = []
    with MDF(filename, remove_source_from_channel_names=True) as mdf:
        for var in SigList:
            try:
                # get group and Index from channel_db
                grp_idx = mdf.channels_db[var][0]
                # Fetch signal as data object
                sigs.append(mdf.get(group=grp_idx[0], index=grp_idx[1]))
                # Append to mdf
            except:
                continue

    tempMDF.append(sigs)
    df = tempMDF.to_dataframe(raster=SampleTime)

    types = df.apply(lambda x: pd.api.types.infer_dtype(x.values))
    for col in types[types == 'bytes'].index:  # String/Enum
        df[col] = df[col].apply(cleanEnumString)

    if (EncodeEnums == True):
        types = df.apply(lambda x: pd.api.types.infer_dtype(x.values))
        for col in types[types == 'string'].index:  # String/Enum
            df[col] = df[col].astype('category')
            df[col] = df[col].cat.codes

    return df
示例#3
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    def export_to_mf4(self):
        print("exporting to mf4")
        timestamps = np.array(self.data['t'])
        voltages = Signal(samples=np.array(self.data['v'], dtype=np.float32),
                          timestamps=timestamps,
                          name='Voltage',
                          unit='V')
        currents = Signal(samples=np.array(self.data['c'], dtype=np.float32),
                          timestamps=timestamps,
                          name='Current',
                          unit='A')
        powers = Signal(samples=np.array(self.data['p'], dtype=np.float32),
                        timestamps=timestamps,
                        name='Power',
                        unit='W')
        capacities = Signal(samples=np.array(self.data['cap'],
                                             dtype=np.float32),
                            timestamps=timestamps,
                            name='Capacity',
                            unit='AH')

        mdf4 = MDF(version='4.10')
        signals = [voltages, currents, powers, capacities]
        mdf4.start_time = self.start_time
        mdf4.append(signals, comment='Battery test: {}'.format(self.cell_id))
        mdf4.save("test.mf4", overwrite=True)
        return mdf4
示例#4
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    def test_mixed(self):

        t = np.arange(15, dtype="<f8")

        s1 = Signal(
            np.frombuffer(b"\x00\x00\x00\x02" * 15, dtype=">u4"), t, name="Motorola"
        )

        s2 = Signal(
            np.frombuffer(b"\x04\x00\x00\x00" * 15, dtype="<u4"), t, name="Intel"
        )

        for version in ("3.30", "4.10"):
            mdf = MDF(version=version)
            mdf.append([s1, s2], common_timebase=True)
            outfile = mdf.save(
                Path(TestEndianess.tempdir.name) / f"out", overwrite=True
            )
            mdf.close()

            with MDF(outfile) as mdf:
                self.assertTrue(np.array_equal(mdf.get("Motorola").samples, [2] * 15))
                self.assertTrue(np.array_equal(mdf.get("Intel").samples, [4] * 15))

        for version in ("3.30", "4.10"):
            mdf = MDF(version=version)
            mdf.append([s2, s1], common_timebase=True)
            outfile = mdf.save(
                Path(TestEndianess.tempdir.name) / f"out", overwrite=True
            )
            mdf.close()

            with MDF(outfile) as mdf:
                self.assertTrue(np.array_equal(mdf.get("Motorola").samples, [2] * 15))
                self.assertTrue(np.array_equal(mdf.get("Intel").samples, [4] * 15))
示例#5
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    def test_mixed(self):

        t = np.arange(15, dtype='<f8')

        s1 = Signal(
            np.frombuffer(b'\x00\x00\x00\x02' * 15, dtype='>u4'),
            t,
            name='Motorola'
        )

        s2 = Signal(
            np.frombuffer(b'\x04\x00\x00\x00' * 15, dtype='<u4'),
            t,
            name='Intel'
        )

        for version in ('3.30', '4.10'):
            mdf = MDF(version=version)
            mdf.append([s1, s2], common_timebase=True)
            outfile = mdf.save(
                Path(TestEndianess.tempdir.name) / f"out",
                overwrite=True,
            )
            mdf.close()

            with MDF(outfile) as mdf:
                self.assertTrue(
                    np.array_equal(
                        mdf.get('Motorola').samples, [2,] * 15
                    )
                )
                self.assertTrue(
                    np.array_equal(
                        mdf.get('Intel').samples, [4,] * 15
                    )
                )

        for version in ('3.30', '4.10'):
            mdf = MDF(version=version)
            mdf.append([s2, s1], common_timebase=True)
            outfile = mdf.save(
                Path(TestEndianess.tempdir.name) / f"out",
                overwrite=True,
            )
            mdf.close()

            with MDF(outfile) as mdf:
                self.assertTrue(
                    np.array_equal(
                        mdf.get('Motorola').samples, [2,] * 15
                    )
                )
                self.assertTrue(
                    np.array_equal(
                        mdf.get('Intel').samples, [4,] * 15
                    )
                )
示例#6
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    def test_iter_groups(self):
        dfs = [
            DataFrame({
                f'df_{i}_column_0': np.ones(5) * i,
                f'df_{i}_column_1': np.arange(5) * i
            }) for i in range(5)
        ]

        mdf = MDF()
        for df in dfs:
            mdf.append(df)

        for i, mdf_df in enumerate(mdf.iter_groups()):
            self.assertTrue(mdf_df.equals(dfs[i]))
示例#7
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    def test_resample_raster_0(self):
        sigs = [
            Signal(
                samples=np.ones(1000) * i,
                timestamps=np.arange(1000),
                name=f'Signal_{i}',
            ) for i in range(20)
        ]

        mdf = MDF()
        mdf.append(sigs)
        mdf.configure(read_fragment_size=1)
        with self.assertRaises(AssertionError):
            mdf = mdf.resample(raster=0)
示例#8
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    def test_resample_raster_0(self):
        sigs = [
            Signal(
                samples=np.ones(1000) * i,
                timestamps=np.arange(1000),
                name=f'Signal_{i}',
            ) for i in range(20)
        ]

        mdf = MDF()
        mdf.append(sigs)
        mdf.configure(read_fragment_size=1)
        mdf = mdf.resample(raster=0)

        for i, sig in enumerate(mdf.iter_channels(skip_master=True)):
            self.assertTrue(np.array_equal(sig.samples, sigs[i].samples))
            self.assertTrue(np.array_equal(sig.timestamps, sigs[i].timestamps))
示例#9
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文件: erg.py 项目: kaipyroami/mfile
 def export_mdf(self):
     mdf = MDF()
     mdf.header.start_time = self.start_time
     sigs = []
     cntr = 0
     for name in self.signals:
         if name == "Time":
             continue
         sigs.append(self.get(name, True))
         if sigs[-1].samples.dtype.kind == "S":
             sigs[-1].encoding = "utf-8"
         cntr += 1
         if cntr == 200:
             cntr = 0
             mdf.append(sigs, common_timebase=True)
             sigs = []
     if sigs:
         mdf.append(sigs, common_timebase=True)
     return mdf
示例#10
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    def test_to_dataframe(self):
        dfs = [
            DataFrame({
                f'df_{i}_column_0': np.ones(5) * i,
                f'df_{i}_column_1': np.arange(5) * i
            }) for i in range(5)
        ]

        mdf = MDF()
        for df in dfs:
            mdf.append(df)

        target = {}
        for i in range(5):
            target[f'df_{i}_column_0'] = np.ones(5) * i
            target[f'df_{i}_column_1'] = np.arange(5) * i

        target = DataFrame(target)

        self.assertTrue(target.equals(mdf.to_dataframe()))
示例#11
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conversion = {'lower_{}'.format(i): i * 10 for i in range(vals)}
conversion.update({'upper_{}'.format(i): (i + 1) * 10 for i in range(vals)})
conversion.update(
    {'text_{}'.format(i): 'Level {}'.format(i)
     for i in range(vals)})
conversion['default'] = b'Unknown level'
sig = Signal(
    6 * np.arange(cycles, dtype=np.uint64) % 240,
    t,
    name='Channel_value_range_to_text',
    conversion=conversion,
    comment='Value range to text channel',
)
sigs.append(sig)

mdf.append(sigs, 'single dimensional channels', common_timebase=True)

sigs = []

# lookup tabel with axis
samples = [
    np.ones((cycles, 2, 3), dtype=np.uint64) * 1,
    np.ones((cycles, 2), dtype=np.uint64) * 2,
    np.ones((cycles, 3), dtype=np.uint64) * 3,
]

types = [
    ('Channel_lookup_with_axis', '(2, 3)<u8'),
    ('channel_axis_1', '(2, )<u8'),
    ('channel_axis_2', '(3, )<u8'),
]
示例#12
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def generate_test_files(version="4.10"):
    cycles = 3000
    channels_count = 2000
    mdf = MDF(version=version)

    if version <= "3.30":
        filename = r"test.mdf"
    else:
        filename = r"test.mf4"

    if os.path.exists(filename):
        return filename

    t = np.arange(cycles, dtype=np.float64)

    cls = v4b.ChannelConversion if version >= "4.00" else v3b.ChannelConversion

    # no conversion
    sigs = []
    for i in range(channels_count):
        sig = Signal(
            np.ones(cycles, dtype=np.uint64) * i,
            t,
            name="Channel_{}".format(i),
            unit="unit_{}".format(i),
            conversion=None,
            comment="Unsigned int 16bit channel {}".format(i),
            raw=True,
        )
        sigs.append(sig)
    mdf.append(sigs, common_timebase=True)

    # linear
    sigs = []
    for i in range(channels_count):
        conversion = {
            "conversion_type":
            v4c.CONVERSION_TYPE_LIN
            if version >= "4.00" else v3c.CONVERSION_TYPE_LINEAR,
            "a":
            float(i),
            "b":
            -0.5,
        }
        sig = Signal(
            np.ones(cycles, dtype=np.int64),
            t,
            name="Channel_{}".format(i),
            unit="unit_{}".format(i),
            conversion=cls(**conversion),
            comment="Signed 16bit channel {} with linear conversion".format(i),
            raw=True,
        )
        sigs.append(sig)
    mdf.append(sigs, common_timebase=True)

    # algebraic
    sigs = []
    for i in range(channels_count):
        conversion = {
            "conversion_type":
            v4c.CONVERSION_TYPE_ALG
            if version >= "4.00" else v3c.CONVERSION_TYPE_FORMULA,
            "formula":
            "{} * sin(X)".format(i),
        }
        sig = Signal(
            np.arange(cycles, dtype=np.int32) / 100.0,
            t,
            name="Channel_{}".format(i),
            unit="unit_{}".format(i),
            conversion=cls(**conversion),
            comment="Sinus channel {} with algebraic conversion".format(i),
            raw=True,
        )
        sigs.append(sig)
    mdf.append(sigs, common_timebase=True)

    # rational
    sigs = []
    for i in range(channels_count):
        conversion = {
            "conversion_type":
            v4c.CONVERSION_TYPE_RAT
            if version >= "4.00" else v3c.CONVERSION_TYPE_RAT,
            "P1":
            0,
            "P2":
            i,
            "P3":
            -0.5,
            "P4":
            0,
            "P5":
            0,
            "P6":
            1,
        }
        sig = Signal(
            np.ones(cycles, dtype=np.int64),
            t,
            name="Channel_{}".format(i),
            unit="unit_{}".format(i),
            conversion=cls(**conversion),
            comment="Channel {} with rational conversion".format(i),
            raw=True,
        )
        sigs.append(sig)
    mdf.append(sigs, common_timebase=True)

    # string
    sigs = []
    for i in range(channels_count):
        sig = [
            "Channel {} sample {}".format(i, j).encode("ascii")
            for j in range(cycles)
        ]
        sig = Signal(
            np.array(sig),
            t,
            name="Channel_{}".format(i),
            unit="unit_{}".format(i),
            comment="String channel {}".format(i),
            raw=True,
        )
        sigs.append(sig)
    mdf.append(sigs, common_timebase=True)

    # byte array
    sigs = []
    ones = np.ones(cycles, dtype=np.dtype("(8,)u1"))
    for i in range(channels_count):
        sig = Signal(
            ones * (i % 255),
            t,
            name="Channel_{}".format(i),
            unit="unit_{}".format(i),
            comment="Byte array channel {}".format(i),
            raw=True,
        )
        sigs.append(sig)
    mdf.append(sigs, common_timebase=True)

    # value to text
    sigs = []
    ones = np.ones(cycles, dtype=np.uint64)
    conversion = {
        "raw":
        np.arange(255, dtype=np.float64),
        "phys":
        np.array(["Value {}".format(i).encode("ascii") for i in range(255)]),
        "conversion_type":
        v4c.CONVERSION_TYPE_TABX
        if version >= "4.00" else v3c.CONVERSION_TYPE_TABX,
        "links_nr":
        260,
        "ref_param_nr":
        255,
    }

    for i in range(255):
        conversion["val_{}".format(i)] = conversion["param_val_{}".format(
            i)] = conversion["raw"][i]
        conversion["text_{}".format(i)] = conversion["phys"][i]
    conversion["text_{}".format(255)] = "Default"

    for i in range(channels_count):
        sig = Signal(
            ones * i,
            t,
            name="Channel_{}".format(i),
            unit="unit_{}".format(i),
            comment="Value to text channel {}".format(i),
            conversion=cls(**conversion),
            raw=True,
        )
        sigs.append(sig)
    mdf.append(sigs, common_timebase=True)

    mdf.save(filename, overwrite=True)
示例#13
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    {"upper_{}".format(i): (i + 1) * 10 - 5
     for i in range(vals)})
conversion.update(
    {"text_{}".format(i): "Level {}".format(i)
     for i in range(vals)})
conversion["default"] = b"Unknown level"
sig = Signal(
    6 * np.arange(cycles, dtype=np.uint64) % 240,
    t,
    name="Channel_value_range_to_text",
    conversion=conversion,
    comment="Value range to text channel",
)
sigs.append(sig)

mdf.append(sigs, "single dimensional channels", common_timebase=True)

sigs = []

# lookup tabel with axis
samples = [
    np.ones((cycles, 2, 3), dtype=np.uint64) * 1,
    np.ones((cycles, 2), dtype=np.uint64) * 2,
    np.ones((cycles, 3), dtype=np.uint64) * 3,
]

types = [
    ("Channel_lookup_with_axis", "(2, 3)<u8"),
    ("channel_axis_1", "(2, )<u8"),
    ("channel_axis_2", "(3, )<u8"),
]
示例#14
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def generate_arrays_test_file(tmpdir):
    version = "4.10"
    mdf = MDF(version=version)
    filename = Path(tmpdir) / f"arrays_test_{version}.mf4"

    if filename.exists():
        return filename

    t = np.arange(cycles, dtype=np.float64)

    # lookup tabel with axis
    sigs = []
    for i in range(array_channels_count):
        samples = [
            np.ones((cycles, 2, 3), dtype=np.uint64) * i,
            np.ones((cycles, 2), dtype=np.uint64) * i,
            np.ones((cycles, 3), dtype=np.uint64) * i,
        ]

        types = [
            ("Channel_{}".format(i), "(2, 3)<u8"),
            ("channel_{}_axis_1".format(i), "(2, )<u8"),
            ("channel_{}_axis_2".format(i), "(3, )<u8"),
        ]

        sig = Signal(
            np.core.records.fromarrays(samples, dtype=np.dtype(types)),
            t,
            name="Channel_{}".format(i),
            unit="unit_{}".format(i),
            conversion=None,
            comment="Array channel {}".format(i),
            raw=True,
        )
        sigs.append(sig)
    mdf.append(sigs, common_timebase=True)

    # lookup tabel with default axis
    sigs = []
    for i in range(array_channels_count):
        samples = [np.ones((cycles, 2, 3), dtype=np.uint64) * i]

        types = [("Channel_{}".format(i), "(2, 3)<u8")]

        sig = Signal(
            np.core.records.fromarrays(samples, dtype=np.dtype(types)),
            t,
            name="Channel_{}".format(i),
            unit="unit_{}".format(i),
            conversion=None,
            comment="Array channel {} with default axis".format(i),
            raw=True,
        )
        sigs.append(sig)
    mdf.append(sigs, common_timebase=True)

    # structure channel composition
    sigs = []
    for i in range(array_channels_count):
        samples = [
            np.ones(cycles, dtype=np.uint8) * i,
            np.ones(cycles, dtype=np.uint16) * i,
            np.ones(cycles, dtype=np.uint32) * i,
            np.ones(cycles, dtype=np.uint64) * i,
            np.ones(cycles, dtype=np.int8) * i,
            np.ones(cycles, dtype=np.int16) * i,
            np.ones(cycles, dtype=np.int32) * i,
            np.ones(cycles, dtype=np.int64) * i,
        ]

        types = [
            ("struct_{}_channel_0".format(i), np.uint8),
            ("struct_{}_channel_1".format(i), np.uint16),
            ("struct_{}_channel_2".format(i), np.uint32),
            ("struct_{}_channel_3".format(i), np.uint64),
            ("struct_{}_channel_4".format(i), np.int8),
            ("struct_{}_channel_5".format(i), np.int16),
            ("struct_{}_channel_6".format(i), np.int32),
            ("struct_{}_channel_7".format(i), np.int64),
        ]

        sig = Signal(
            np.core.records.fromarrays(samples, dtype=np.dtype(types)),
            t,
            name="Channel_{}".format(i),
            unit="unit_{}".format(i),
            conversion=None,
            comment="Structure channel composition {}".format(i),
            raw=True,
        )
        sigs.append(sig)

    mdf.append(sigs, common_timebase=True)

    name = mdf.save(filename, overwrite=True)
示例#15
0
                 timestamps=timestamps,
                 name='Int32_Signal',
                 unit='i4')

# float64
s_float64 = Signal(samples=np.array([-20, -10, 0, 10, 20], dtype=np.float64),
                   timestamps=timestamps,
                   name='Float64_Signal',
                   unit='f8')

# create empty MDf version 4.00 file
mdf4 = MDF(version='4.10')

# append the 3 signals to the new file
signals = [s_uint8, s_int32, s_float64]
mdf4.append(signals, 'Created by Python')

# save new file
mdf4.save('my_new_file.mf4', overwrite=True)

# convert new file to mdf version 3.10 with lowest possible RAM usage
mdf3 = mdf4.convert('3.10', memory='minimum')
print(mdf3.version)

# get the float signal
sig = mdf3.get('Float64_Signal')
print(sig)

# cut measurement from 0.3s to end of measurement
mdf4_cut = mdf4.cut(start=0.3)
mdf4_cut.get('Float64_Signal').plot()
示例#16
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def generate_test_files():
    print('Generating test files:')
    for version in ('3.30', '4.10'):
        print("-> generating file for version", version)
        mdf = MDF(version=version, memory='minimum')

        if version == '3.30':
            cycles = 500
            channels_count = 8000
            filename = 'test.mdf'
        else:
            cycles = 500
            channels_count = 20000
            filename = 'test.mf4'

        if os.path.exists(filename):
            continue

        t = np.arange(cycles, dtype=np.float64)

        # no conversion
        sigs = []
        for i in range(channels_count):
            sig = Signal(
                np.ones(cycles, dtype=np.uint16),
                t,
                name='Channel_{}'.format(i),
                unit='unit_{}'.format(i),
                conversion=None,
                comment='Unsinged int 16bit channel {}'.format(i),
                raw=True,
            )
            sigs.append(sig)
        mdf.append(sigs)

        # linear
        sigs = []
        for i in range(channels_count):
            conversion = {
                'type': SignalConversions.CONVERSION_LINEAR,
                'a': float(i),
                'b': -0.5,
            }
            sig = Signal(
                np.ones(cycles, dtype=np.int16),
                t,
                name='Channel_{}'.format(i),
                unit='unit_{}'.format(i),
                conversion=conversion,
                comment='Signed 16bit channel {} with linear conversion'.
                format(i),
                raw=True,
            )
            sigs.append(sig)
        mdf.append(sigs)

        # algebraic
        sigs = []
        for i in range(channels_count):
            conversion = {
                'type': SignalConversions.CONVERSION_ALGEBRAIC,
                'formula': '{} * sin(X)'.format(i),
            }
            sig = Signal(
                np.arange(cycles, dtype=np.int32) / 100,
                t,
                name='Channel_{}'.format(i),
                unit='unit_{}'.format(i),
                conversion=conversion,
                comment='Sinus channel {} with algebraic conversion'.format(i),
                raw=True,
            )
            sigs.append(sig)
        mdf.append(sigs)

        # rational
        sigs = []
        for i in range(channels_count):
            conversion = {
                'type': SignalConversions.CONVERSION_RATIONAL,
                'P1': 0,
                'P2': i,
                'P3': -0.5,
                'P4': 0,
                'P5': 0,
                'P6': 1,
            }
            sig = Signal(
                np.ones(cycles, dtype=np.int64),
                t,
                name='Channel_{}'.format(i),
                unit='unit_{}'.format(i),
                conversion=conversion,
                comment='Channel {} with rational conversion'.format(i),
                raw=True,
            )
            sigs.append(sig)
        mdf.append(sigs)

        mdf.save(filename, overwrite=True)

        del mdf

        MDF.merge([
            filename,
        ] * 10, version, memory='minimum').save(filename, overwrite=True)
示例#17
0
文件: bench.py 项目: sgd218/asammdf
def generate_test_files(version='4.10'):
    cycles = 3000
    channels_count = 2000
    mdf = MDF(version=version)

    if version <= '3.30':
        filename = r'test.mdf'
    else:
        filename = r'test.mf4'

    if os.path.exists(filename):
        return filename

    t = np.arange(cycles, dtype=np.float64)

    cls = v4b.ChannelConversion if version >= '4.00' else v3b.ChannelConversion

    # no conversion
    sigs = []
    for i in range(channels_count):
        sig = Signal(
            np.ones(cycles, dtype=np.uint64) * i,
            t,
            name='Channel_{}'.format(i),
            unit='unit_{}'.format(i),
            conversion=None,
            comment='Unsigned int 16bit channel {}'.format(i),
            raw=True,
        )
        sigs.append(sig)
    mdf.append(sigs, common_timebase=True)

    # linear
    sigs = []
    for i in range(channels_count):
        conversion = {
            'conversion_type':
            v4c.CONVERSION_TYPE_LIN
            if version >= '4.00' else v3c.CONVERSION_TYPE_LINEAR,
            'a':
            float(i),
            'b':
            -0.5,
        }
        sig = Signal(
            np.ones(cycles, dtype=np.int64),
            t,
            name='Channel_{}'.format(i),
            unit='unit_{}'.format(i),
            conversion=cls(**conversion),
            comment='Signed 16bit channel {} with linear conversion'.format(i),
            raw=True,
        )
        sigs.append(sig)
    mdf.append(sigs, common_timebase=True)

    # algebraic
    sigs = []
    for i in range(channels_count):
        conversion = {
            'conversion_type':
            v4c.CONVERSION_TYPE_ALG
            if version >= '4.00' else v3c.CONVERSION_TYPE_FORMULA,
            'formula':
            '{} * sin(X)'.format(i),
        }
        sig = Signal(
            np.arange(cycles, dtype=np.int32) / 100.0,
            t,
            name='Channel_{}'.format(i),
            unit='unit_{}'.format(i),
            conversion=cls(**conversion),
            comment='Sinus channel {} with algebraic conversion'.format(i),
            raw=True,
        )
        sigs.append(sig)
    mdf.append(sigs, common_timebase=True)

    # rational
    sigs = []
    for i in range(channels_count):
        conversion = {
            'conversion_type':
            v4c.CONVERSION_TYPE_RAT
            if version >= '4.00' else v3c.CONVERSION_TYPE_RAT,
            'P1':
            0,
            'P2':
            i,
            'P3':
            -0.5,
            'P4':
            0,
            'P5':
            0,
            'P6':
            1,
        }
        sig = Signal(
            np.ones(cycles, dtype=np.int64),
            t,
            name='Channel_{}'.format(i),
            unit='unit_{}'.format(i),
            conversion=cls(**conversion),
            comment='Channel {} with rational conversion'.format(i),
            raw=True,
        )
        sigs.append(sig)
    mdf.append(sigs, common_timebase=True)

    # string
    sigs = []
    for i in range(channels_count):
        sig = [
            'Channel {} sample {}'.format(i, j).encode('ascii')
            for j in range(cycles)
        ]
        sig = Signal(
            np.array(sig),
            t,
            name='Channel_{}'.format(i),
            unit='unit_{}'.format(i),
            comment='String channel {}'.format(i),
            raw=True,
        )
        sigs.append(sig)
    mdf.append(sigs, common_timebase=True)

    # byte array
    sigs = []
    ones = np.ones(cycles, dtype=np.dtype('(8,)u1'))
    for i in range(channels_count):
        sig = Signal(
            ones * (i % 255),
            t,
            name='Channel_{}'.format(i),
            unit='unit_{}'.format(i),
            comment='Byte array channel {}'.format(i),
            raw=True,
        )
        sigs.append(sig)
    mdf.append(sigs, common_timebase=True)

    # value to text
    sigs = []
    ones = np.ones(cycles, dtype=np.uint64)
    conversion = {
        'raw':
        np.arange(255, dtype=np.float64),
        'phys':
        np.array(['Value {}'.format(i).encode('ascii') for i in range(255)]),
        'conversion_type':
        v4c.CONVERSION_TYPE_TABX
        if version >= '4.00' else v3c.CONVERSION_TYPE_TABX,
        'links_nr':
        260,
        'ref_param_nr':
        255,
    }

    for i in range(255):
        conversion['val_{}'.format(i)] = conversion['param_val_{}'.format(
            i)] = conversion['raw'][i]
        conversion['text_{}'.format(i)] = conversion['phys'][i]
    conversion['text_{}'.format(255)] = 'Default'

    for i in range(channels_count):
        sig = Signal(
            ones * i,
            t,
            name='Channel_{}'.format(i),
            unit='unit_{}'.format(i),
            comment='Value to text channel {}'.format(i),
            conversion=cls(**conversion),
            raw=True,
        )
        sigs.append(sig)
    mdf.append(sigs, common_timebase=True)

    mdf.save(filename, overwrite=True)