<h2>org.das2.datum.UnitsUtil</h2><p>Useful operations for units, and tests for Steven's Levels of Measurement.</p> <hr> <a name="divide"></a> <h2>divide</h2> divide( <a href='http://www-pw.physics.uiowa.edu/~jbf/autoplot/doc/org/das2/datum/Datum.html'>Datum</a> aDatum, <a href='http://www-pw.physics.uiowa.edu/~jbf/autoplot/doc/org/das2/datum/Datum.html'>Datum</a> bDatum ) → <a href='http://www-pw.physics.uiowa.edu/~jbf/autoplot/doc/org/das2/datum/Datum.html'>Datum</a> <p>attempt to perform the division of two Datums by looking for convertible units or dimensionless.</p> <h3>Parameters</h3> aDatum - the numerator <br> bDatum - the denominator <h3>Returns:</h3> the result <br><br> <a href="https://github.com/autoplot/dev/search?q=divide&unscoped_q=divide">[search for examples]</a> <a href="https://github.com/autoplot/documentation/tree/master/javadoc/org/das2/datum/UnitsUtil.md">[view on GitHub]</a> <a href="http://www-pw.physics.uiowa.edu/~jbf/autoplot/javadoc2018/org/das2/datum/UnitsUtil.html#divide">[view on old javadoc]</a> <a href="https://saturn.physics.uiowa.edu/svn/das2/dasCore/community/autoplot2011/trunk/dasCoreDatum/src/org/das2/datum/UnitsUtil.java">[view source]</a> <br> <br> <hr> <a name="divideToString"></a> <h2>divideToString</h2> divideToString( <a href='http://www-pw.physics.uiowa.edu/~jbf/autoplot/doc/org/das2/datum/Datum.html'>Datum</a> aDatum, <a href='http://www-pw.physics.uiowa.edu/~jbf/autoplot/doc/org/das2/datum/Datum.html'>Datum</a> bDatum ) → <a href='https://docs.oracle.com/javase/8/docs/api/java/lang/String.html'>String</a> <p>Special division operation that either does the Datum division if possible, or returns the division of the magnitude parts of the Datums plus the unit names "A/B", suitable for human consumption.</p> <h3>Parameters</h3> aDatum - the numerator <br> bDatum - the denominator <h3>Returns:</h3> String for the result, or "A/B" <br><br> <a href="https://github.com/autoplot/dev/search?q=divideToString&unscoped_q=divideToString">[search for examples]</a> <a href="https://github.com/autoplot/documentation/tree/master/javadoc/org/das2/datum/UnitsUtil.md">[view on GitHub]</a> <a href="http://www-pw.physics.uiowa.edu/~jbf/autoplot/javadoc2018/org/das2/datum/UnitsUtil.html#divideToString">[view on old javadoc]</a> <a href="https://saturn.physics.uiowa.edu/svn/das2/dasCore/community/autoplot2011/trunk/dasCoreDatum/src/org/das2/datum/UnitsUtil.java">[view source]</a> <br> <br> <hr> <a name="getInverseUnit"></a> <h2>getInverseUnit</h2> getInverseUnit( <a href='http://www-pw.physics.uiowa.edu/~jbf/autoplot/doc/org/das2/datum/Units.html'>Units</a> unit ) → <a href='http://www-pw.physics.uiowa.edu/~jbf/autoplot/doc/org/das2/datum/Units.html'>Units</a> <p>returns the unit whose product with the parameter unit is unity. (Presently this is only supports time units like Hz→seconds).</p> <h3>Parameters</h3> unit - the unit <h3>Returns:</h3> the inverse unit, or throws exception if one is not known. <br><br> <a href="https://github.com/autoplot/dev/search?q=getInverseUnit&unscoped_q=getInverseUnit">[search for examples]</a> <a href="https://github.com/autoplot/documentation/tree/master/javadoc/org/das2/datum/UnitsUtil.md">[view on GitHub]</a> <a href="http://www-pw.physics.uiowa.edu/~jbf/autoplot/javadoc2018/org/das2/datum/UnitsUtil.html#getInverseUnit">[view on old javadoc]</a> <a href="https://saturn.physics.uiowa.edu/svn/das2/dasCore/community/autoplot2011/trunk/dasCoreDatum/src/org/das2/datum/UnitsUtil.java">[view source]</a> <br> <br> <hr> <a name="isIntervalMeasurement"></a> <h2>isIntervalMeasurement</h2> isIntervalMeasurement( <a href='http://www-pw.physics.uiowa.edu/~jbf/autoplot/doc/org/das2/datum/Units.html'>Units</a> unit ) → boolean <p>returns true if the unit is a interval measurement, meaning the choice of zero is arbitrary. Subtraction and comparison are allowed, but addition, multiplication and division are invalid operators. Examples include "2008-04-09T14:27:00Z" and 15 deg W Longitude.</p> <h3>Parameters</h3> unit - an Units <h3>Returns:</h3> a boolean <h3>See Also:</h3> <a href='http://en.wikipedia.org/wiki/Level_of_measurement'>http://en.wikipedia.org/wiki/Level_of_measurement</a> <br> <a href='http://www.statisticssolutions.com/data-levels-of-measurement/'>http://www.statisticssolutions.com/data-levels-of-measurement/</a> <br> <br><br> <a href="https://github.com/autoplot/dev/search?q=isIntervalMeasurement&unscoped_q=isIntervalMeasurement">[search for examples]</a> <a href="https://github.com/autoplot/documentation/tree/master/javadoc/org/das2/datum/UnitsUtil.md">[view on GitHub]</a> <a href="http://www-pw.physics.uiowa.edu/~jbf/autoplot/javadoc2018/org/das2/datum/UnitsUtil.html#isIntervalMeasurement">[view on old javadoc]</a> <a href="https://saturn.physics.uiowa.edu/svn/das2/dasCore/community/autoplot2011/trunk/dasCoreDatum/src/org/das2/datum/UnitsUtil.java">[view source]</a> <br> <br> <hr> <a name="isIntervalOrRatioMeasurement"></a> <h2>isIntervalOrRatioMeasurement</h2> isIntervalOrRatioMeasurement( <a href='http://www-pw.physics.uiowa.edu/~jbf/autoplot/doc/org/das2/datum/Units.html'>Units</a> unit ) → boolean <p>returns true if the unit is a interval measurement or is a ratio measurement, and not a nominal or ordinal measurement. These are things that are plotted by showing a location on an axis. See http://en.wikipedia.org/wiki/Level_of_measurement Examples include "2008-04-09T14:27:00Z" and "5 km"</p> <h3>Parameters</h3> unit - an Units <h3>Returns:</h3> a boolean <br><br> <a href="https://github.com/autoplot/dev/search?q=isIntervalOrRatioMeasurement&unscoped_q=isIntervalOrRatioMeasurement">[search for examples]</a> <a href="https://github.com/autoplot/documentation/tree/master/javadoc/org/das2/datum/UnitsUtil.md">[view on GitHub]</a> <a href="http://www-pw.physics.uiowa.edu/~jbf/autoplot/javadoc2018/org/das2/datum/UnitsUtil.html#isIntervalOrRatioMeasurement">[view on old javadoc]</a> <a href="https://saturn.physics.uiowa.edu/svn/das2/dasCore/community/autoplot2011/trunk/dasCoreDatum/src/org/das2/datum/UnitsUtil.java">[view source]</a> <br> <br> <hr> <a name="isNominalMeasurement"></a> <h2>isNominalMeasurement</h2> isNominalMeasurement( <a href='http://www-pw.physics.uiowa.edu/~jbf/autoplot/doc/org/das2/datum/Units.html'>Units</a> unit ) → boolean <p>returns true if the unit is nominal, meaning that Datums with this unit can only be equal or not equal. Currently all nominal data is stored as ordinal data, so this always returns false. Examples include "Iowa City", and "Voyager 1". See http://en.wikipedia.org/wiki/Level_of_measurement</p> <h3>Parameters</h3> unit - the unit <h3>Returns:</h3> true if the unit is nominal. <br><br> <a href="https://github.com/autoplot/dev/search?q=isNominalMeasurement&unscoped_q=isNominalMeasurement">[search for examples]</a> <a href="https://github.com/autoplot/documentation/tree/master/javadoc/org/das2/datum/UnitsUtil.md">[view on GitHub]</a> <a href="http://www-pw.physics.uiowa.edu/~jbf/autoplot/javadoc2018/org/das2/datum/UnitsUtil.html#isNominalMeasurement">[view on old javadoc]</a> <a href="https://saturn.physics.uiowa.edu/svn/das2/dasCore/community/autoplot2011/trunk/dasCoreDatum/src/org/das2/datum/UnitsUtil.java">[view source]</a> <br> <br> <hr> <a name="isOrdinalMeasurement"></a> <h2>isOrdinalMeasurement</h2> isOrdinalMeasurement( <a href='http://www-pw.physics.uiowa.edu/~jbf/autoplot/doc/org/das2/datum/Units.html'>Units</a> unit ) → boolean <p>returns true if the unit is ordinal, meaning that Datums with this unit can only be equal or not equal, or compared. subtract, add, multiply, divide are invalid. Examples include energy bin labels and quality measures. See http://en.wikipedia.org/wiki/Level_of_measurement</p> <h3>Parameters</h3> unit - an Units <h3>Returns:</h3> true if the unit is ordinal. <br><br> <a href="https://github.com/autoplot/dev/search?q=isOrdinalMeasurement&unscoped_q=isOrdinalMeasurement">[search for examples]</a> <a href="https://github.com/autoplot/documentation/tree/master/javadoc/org/das2/datum/UnitsUtil.md">[view on GitHub]</a> <a href="http://www-pw.physics.uiowa.edu/~jbf/autoplot/javadoc2018/org/das2/datum/UnitsUtil.html#isOrdinalMeasurement">[view on old javadoc]</a> <a href="https://saturn.physics.uiowa.edu/svn/das2/dasCore/community/autoplot2011/trunk/dasCoreDatum/src/org/das2/datum/UnitsUtil.java">[view source]</a> <br> <br> <hr> <a name="isRatioMeasurement"></a> <h2>isRatioMeasurement</h2> isRatioMeasurement( <a href='http://www-pw.physics.uiowa.edu/~jbf/autoplot/doc/org/das2/datum/Units.html'>Units</a> unit ) → boolean <p>returns true if the unit is a ratio measurement, meaning there is a physical zero and you can make meaningful ratios between arbitrary numbers. All operations like add, multiply and divide are allowed. Examples include "5 km" or "0.2/cc" and "15 counts"</p> <h3>Parameters</h3> unit - an Units <h3>Returns:</h3> a boolean <h3>See Also:</h3> <a href='http://en.wikipedia.org/wiki/Level_of_measurement'>http://en.wikipedia.org/wiki/Level_of_measurement</a> <br> <a href='http://www.statisticssolutions.com/data-levels-of-measurement/'>http://www.statisticssolutions.com/data-levels-of-measurement/</a> <br> <a href='https://www.questionpro.com/blog/nominal-ordinal-interval-ratio/'>https://www.questionpro.com/blog/nominal-ordinal-interval-ratio/</a> <br> <br><br> <a href="https://github.com/autoplot/dev/search?q=isRatioMeasurement&unscoped_q=isRatioMeasurement">[search for examples]</a> <a href="https://github.com/autoplot/documentation/tree/master/javadoc/org/das2/datum/UnitsUtil.md">[view on GitHub]</a> <a href="http://www-pw.physics.uiowa.edu/~jbf/autoplot/javadoc2018/org/das2/datum/UnitsUtil.html#isRatioMeasurement">[view on old javadoc]</a> <a href="https://saturn.physics.uiowa.edu/svn/das2/dasCore/community/autoplot2011/trunk/dasCoreDatum/src/org/das2/datum/UnitsUtil.java">[view source]</a> <br> <br> <hr> <a name="isRatiometric"></a> <h2>isRatiometric</h2> isRatiometric( <a href='http://www-pw.physics.uiowa.edu/~jbf/autoplot/doc/org/das2/datum/Units.html'>Units</a> unit ) → boolean <p>returns true if the unit is used to measure distance in a logarithmic space, such as decibels or percent increase. Note Units.dimensionless are not considered ratiometric. (Of course, all ratiometic units are dimensionless...) Do not confuse this with isRatioMeasurement. "5kg" is ratio measurement. "105%" is ratiometric.</p> <h3>Parameters</h3> unit - the unit <h3>Returns:</h3> true if the unit is used to measure distance in a logarithmic space <br><br> <a href="https://github.com/autoplot/dev/search?q=isRatiometric&unscoped_q=isRatiometric">[search for examples]</a> <a href="https://github.com/autoplot/documentation/tree/master/javadoc/org/das2/datum/UnitsUtil.md">[view on GitHub]</a> <a href="http://www-pw.physics.uiowa.edu/~jbf/autoplot/javadoc2018/org/das2/datum/UnitsUtil.html#isRatiometric">[view on old javadoc]</a> <a href="https://saturn.physics.uiowa.edu/svn/das2/dasCore/community/autoplot2011/trunk/dasCoreDatum/src/org/das2/datum/UnitsUtil.java">[view source]</a> <br> <br> <hr> <a name="isTimeLocation"></a> <h2>isTimeLocation</h2> isTimeLocation( <a href='http://www-pw.physics.uiowa.edu/~jbf/autoplot/doc/org/das2/datum/Units.html'>Units</a> unit ) → boolean <p>returns true if the unit describes a location in time, as in us2000 or Units.lookupTimeUnits('seconds since 1989-12-13T00:00Z')</p> <h3>Parameters</h3> unit - the unit to test <h3>Returns:</h3> true if the unit describes a location in time <br><br> <a href="https://github.com/autoplot/dev/search?q=isTimeLocation&unscoped_q=isTimeLocation">[search for examples]</a> <a href="https://github.com/autoplot/documentation/tree/master/javadoc/org/das2/datum/UnitsUtil.md">[view on GitHub]</a> <a href="http://www-pw.physics.uiowa.edu/~jbf/autoplot/javadoc2018/org/das2/datum/UnitsUtil.html#isTimeLocation">[view on old javadoc]</a> <a href="https://saturn.physics.uiowa.edu/svn/das2/dasCore/community/autoplot2011/trunk/dasCoreDatum/src/org/das2/datum/UnitsUtil.java">[view source]</a> <br> <br>