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Name | Data type | Exists? | Description | Convention / example | Schema |
rawName | utf8 | O | original signal name if this had to be reformatted to be used as hdf5 name. | ||
unit | unit_str | A | name of the unit of the signal. This defines the quantity of the experiment variable. | “m/s”, “-“, “rad” | sp1, da1 |
signalType | prop_str | NS | defines the experiment variable or simulation property or the kind of quantity, see Signal Type. | “velocity”, etc “angular velocity” | sp1, da1 |
description | utf8 | A | description of the signal. More detail than name. E.g. the kind of quantity or experiment variable; whether it is an absolute value or a delta. | (tbd) | |
timeOffset | float64 | NS | the time offset in seconds between real start time and the moment the timestamp is created. | da1 | |
order | int32 | O | In case of frequency data specifies whether it is a first or second order effect or otherwise. | 1: first order. 2: second order. -1: Not applicable. | da1 |
minimum | ds_type | O | lowest value in the dataset | sp1 | |
maximum | ds_type | O | highest value in the dataset | sp1 | |
mean | ds_type | O | mean or average value of the dataset (tbd: weighted arithmetic mean?) | sp1 | |
standardDeviation | ds_type | O | standard deviation of the values in the dataset | sp1 | |
position | float64[3] | NS | location of the variable in the specified Coordinate System. | [0.0, 0.0, 0.0] | da1 |
direction | float64[3] | NS | direction of the signal c.q. experiment variable in the specified CS. In case of a rotation it is the direction of the axis of rotation. | Roll in ACK: [1.0,0.0,0.0] Sway in ACK: [0.0, 1.0, 0.0] | da1 |
referenceSystem | utf8 | NS | specifies in which Coordinate Sytem position and direction are given. | “ACK”, (todo: complete list) | da1 |
signalSource | utf8 | O | holds information about the sensor. Depends on system used. Also contains the original signal name from the measurement system. | (tbd) | |
channelNo | int32 | O | if no sensor information is provided holds the channel number in case of measured data. | 123 | |
bases | obj_ref[] | O | List of object references to all datasets that are a master signal to this signal. | [objRef(“time”)] | h5m |
baseNames | utf8[] | O | Names of the base signals (informational only. Not intended for rebuilding the datamodel) | h5m | |
notes | utf8 | A | Any additional information about this signal. | (free text) | |
writeErrors | utf8[] | O | Specifies any errors that occurred while writing the signal (dataset). Mostly value errors. |
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The unit_str is a variable length HDF string . The content is human and computer readable. Therefore any unit is limited to a predefined list of acceptable units and formatted using a specific unit definition notation.
Examples of unit definition strings: "N.m", "kg.m^2/s^3", "kg.m.s^-2"
A list of available or possible values is available at MARIN and here, and is not part of this convention (and probably never will be).
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