Skip to content

Latest commit

 

History

History

com.ibm.streamsx.health.prepare.uomconverter

README.md

Unit of Measure Conversion Service

The com.ibm.streamsx.health.prepare.uomconverter is capable of converting reading values in Observation tuples from one unit of measure to another. The unit of measures that are currently supported for conversion are:

  • Voltage - convert voltage from one metric value to another (i.e. V to mV)
  • Temperature - convert Celcius to/from Farhenheit
  • Frequency - convert beats per minute to/from beats per second

After conversion, the UOM Conversion service returns an Observation tuple containing the converted value and new unit of measure. If a mapping does not exist for the unit of measure set in the Observation tuple, then the input tuple is passed through unchanged.

Mapping File

The UOM Service relies on a user-defined mapping file to indicate the units that should be converted. The mapping file should contain a separate mapping per line. The format of a mapping is as follows:

<fromUnit>|<toUnit>

where <fromUnit> is the unit you want to convert from, and <toUnit> is the unit you want to convert to. Here is an example of a mapping file where all milli volt values are converted to micro volt and all Fahrenheit temperatures are converted to Celcius:

mV|uV
F|C

Supported Unit Formats

The following is a list of unit formats that are supported.

IMPORTANT: Unit spellings are case-sensitive. Misspelling a unit may result in the service failing to run.

Voltage

Unit Description Unit Description
YV yotta-volt cV centi-volt
ZV zetta-volt mV milli-volt
EV exa-volt uV micro-volt
PV peta-volt µV micro-volt
TV terra-volt nV nano-volt
GV giga-volt pV pico-volt
MV mega-volt fV femto-volt
kV kilo-volt aV atto-volt
hV hecto-volt zV zepto-volt
daV deka-volt yV yocto-volt
dV deci-volt

Temperature

Unit Description
C Celcius
°C Celcius
F Fahrenheit
°F Fahrenheit

Frequency

Unit Description
bpm beats per minute
bps beats per second

Dependencies

This service contains the following dependencies:

Expected Input

This service expects an Observation tuple as input:

{
  "patientId" : string,
  "device" : {
    "id" : string,
    "locationId" : string
  },
  "readingSource" : {
    "id" : string,
    "sourceType" : string,
    "deviceId" : string
  },
  "reading" : {
    "ts" : numeric,
    "readingType" : {
      "system" : string,
      "code" : string
    },
    "value" : numeric,
    "uom" : string
  }
}

Output

  • Published Topics: "prepare-uom-converter"
  • Output JSON Schema: Observation Type
{
  "patientId" : string,
  "device" : {
    "id" : string,
    "locationId" : string
  },
  "readingSource" : {
    "id" : string,
    "sourceType" : string,
    "deviceId" : string
  },
  "reading" : {
    "ts" : numeric,
    "readingType" : {
      "system" : string,
      "code" : string
    },
    "value" : numeric,
    "uom" : string
  }
}

Build

Run the following command to build the service:

gradle build

Execute

The service properties, including the path to the mapping file, can be set in the uom.service.properties file. The following properties are available:

Property Description Default
mapFile A relative or absolute path to the mapping file. ./unitmapping.properties
subscriptionTopic The topic that the service should subscribe to. ingest-beacon
debug Enables and disables debug mode (true or false) false

To submit the service the local instance, run the following command:

gradle execute