Units conversion

[BHarris]

I notice that one of the column properties is "units", which assume to mean things like "feet", "kilometers", etc.

Is there a hidden feature that will allow the user to change the column to different units easily?  E.g., if input data is in "feet", the user could right click the column header and see an option to change the units to "meters" and the column values would change?

Also, if JMP could detect the units from the column header, e.g. len(m) = length in meters --> column header as "len" and units as "meters".

[Ryan_Gilmore]

We are archiving this request. If this is still important please comment with additional details and we will reopen. Thank you!

[jmv]

This is important because formulas without unit conversions have very limited capabilities. JMP has an excellent formula editor but it will never be fully advantageous for performing meaningful calculations until it can automatically convert units. Thirty year old calculators like the HP 48GX can recognize and convert units so it should be possible with modern programming and computational advancements?

[Bernd2Heinen]

Specifying the Units property suggests that something could be done with it. But this is not the case. A few versions ago JMP introduced the ability to fully customize date/time formats. It would be very helpful to have a similar feature for units conversion that works in formulas and reports.

[Jeff_Perkinson]

Can you give us some more details on how you would want this work?

If I enter a column as feet and then change it to inches would you want it to just format all the values by multiplying by 12? What should happen to other columns that depend on this column in a formula? Wouldn't that be confusing?

Or would you want it to multiply all the values by 12? What would happen to other formula columns that depended on this original column?

Admittedly, some built-in functions to convert between units would be useful. Check out Conversion Function Library which adds a whole bunch of common conversions to the Formula Editor, and JSL.

[BHarris]

@Jeff_Perkinson :  Sure!  If units were provided, e.g. "rng (ft)", the column would put "ft" in the units property.  Then, if the user switched the units, JMP would multiply all the values in the column by the conversion factor.  Even better if there was a setting to auto-recognize units, e.g., rng(ft), speed_m/s, time{s}, rate[deg/s], accel(m/s2).

Alternatively, the column properties could have a bias/gain property added, and the original values could remain the same, but JMP would always show/plot the modified values.  A unit change would simply adjust the gain.

Handling of formula columns that referenced the source column would depend on whether they had a units property set.  If they did, the input units would be accounted for, e.g. if you had a table with speed (m/s), time (s), and distance (km) columns, then if speed were changed to mph, the speed column would appear to change, but the distance column would not.

The unix utility "units" supports derived units, so it may be a good reference for how to manage this.

[Bernd2Heinen]

Perhaps the date/time functionality could serve as an example. Internally, all values are represented in seconds but the representation differs. Also, there are functions available that allow time/date conversions. That would imply that a set of conversions is required for each physical or non-physical quantity for which this conversion shall be offered. There is a potential conflict between a formatting option and the Units property. Currently, it is possible to format a column with a date format but assign it an arbitrary unit (miles). The Conversion addin shows how those conversion functions could become part of the formula editor plus that the required change takes place when the format (or unit) property changes.