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HP Forum Archive 14

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converting units
Message #1 Posted by Brady Wilson on 8 Sept 2004, 11:44 a.m.

I have a HP49G that I got back in 2001, and I have never been able to figure out how to convert units like ft into meters. Any help would be great, Thanks


Re: converting units
Message #2 Posted by Vieira, Luiz C. (Brazil) on 8 Sept 2004, 1:12 p.m.,
in response to message #1 by Brady Wilson

Hi, Brady;

let's take a brief tour. Find the [6] key and check for[CONVERT] (in blue, meaning [left-shift] prefix key first) and [UNITS] (in red, menaing [right-shift] prefix key first) printed in the keyboard faceplate over it.

Now key in the number you want to be converted, say, from ft to meter (m). Now call [UNITS], select second option (lenght) with down-arrow key, confirm with [OK] ([F6] key) and you'll see the lenght menu.

Select option 5 with 'ft' on it and confirm. You'll see your number with a unit attached to it (e.g.: 10_ft): this is the "from" part, a value unit with, O.K.?

Now enter a second unit object with any value having the "to" convertion unit (you can follow the same procedure and add a 1_m, for example).

Now calll [UNITS] (last time) and press [OK], because you want a tool to convert from 10_ft to _m and [Tools] is already selected. The first tool is already [Convert], so you press [OK] again and you'll see (hopefully): 3.048_m.

You can create any compound unit and convert to any other, since they are compatible. And you can also read/download the HP49G+ Training Modules, available at the HP49G+ page under "Training Modules', like the Units Conversion module. This particular feature, as many others, work the same for both 49G and 49G+.

Have you found any problems on doing or understanding what I wrote, let us know.

Hope you succeed.


Luiz (Brazil)

Edited: 8 Sept 2004, 1:24 p.m.

Re: converting units
Message #3 Posted by Richard Garner on 8 Sept 2004, 3:03 p.m.,
in response to message #2 by Vieira, Luiz C. (Brazil)

Hi Luiz,

No offense, but, I'm glad I bought a 48GX and not a a 49G. If I had, I would have thrown it in the trash the first day. I bought the 48GX specifically for the unit conversion. In my work, I read allot of property deeds and subdivision plats, some of them going back 150+ years with different units from feet, chains, rods, furlongs, links, meters, yards, etc. Sometimes even different units on the same parcel from call to call.

Unit conversions are much easier on the 48GX than on the 49G. You select units, then select the group (length), enter the number (10) press the the key for (feet), 10_ft shows in the display, then press the (left shift)key and what you want it converted to (meters) and it displays 3.0480_m.

It looks like HP took something real simple and made it too complicated to be useful.

Re: converting units
Message #4 Posted by Tim Wessman on 8 Sept 2004, 3:15 p.m.,
in response to message #3 by Richard Garner

Unit conversions is exactly the same on the 49g/g+ as the 48. he was describing algebraic unit conversions. The RPN mode is identical with a few updated units if i remember correctly.

"After you set Flag 117"
Message #5 Posted by Ron Ross on 8 Sept 2004, 3:25 p.m.,
in response to message #4 by Tim Wessman

You have to set flag 117 and THEN the 49G or 49G+ acts just like an Hp48G.

Then all you do is key in the ### and the units you have, then use the left shif key and the units you want. Voila! Answer.

Re: converting units
Message #6 Posted by Vieira, Luiz C. (Brazil) on 8 Sept 2004, 4:40 p.m.,
in response to message #2 by Vieira, Luiz C. (Brazil)

Hi, falks;

thaks for your feedback.

I should have written that this is the lower-level conversion sequence, and that there are other ways (I almost always write this; I missed this one). I simply followed the steps I'd have done without using any shortcut or user's guide information because this is, as I see, the "WYSIWYG" way, simply using screen information. Maybe I'm wrong... Sorry!

And Tim, my HP49G+ is in RPN mode. I rarely use it in Algebraic. Please, correct me if I am wrong: if I add [CONVERT] while in Algebraic mode, the command line returns CONVERT(), right? It does not act instantaneously as I wrote. And you made me remember that the HP49G default mode is Algebraic, not RPN, and I should have asked first which mode Brady wants to use OR show both ways. Thanks!

About flag 117: thanks, Ron; you're right. I thought (again) that having to set a flag in order to make the HP49G/G+ act like the HP48 would not be as good as showing how to use the feature with the calculator "as is", and so allowing fewer operation errors.

Thanks, guys.

Luiz (Brasil)

Edited: 8 Sept 2004, 4:47 p.m.

Re: converting units
Message #7 Posted by James M. Prange on 8 Sept 2004, 9:10 p.m.,
in response to message #2 by Vieira, Luiz C. (Brazil)

I'll add that you can also make your own user-defined units. For example, '7_d' 'week' STO. As long as the user-defined unit is found on the path, it can be used much as the built-in units are used. But note that you can't redefine built-in units (or built-in units with built-in prefixes).

There's also a base unit that isn't very well-documented, the '?' unit. This could be useful for currency conversions; for example, if you define currencies in terms of 'n_?' (where n is a real number), then you can convert among currencies (or compound units including currencies) with dimensional consistency checked.

If you include units in a custom or temporary menu without defining actions for the shifted keyplanes, then the menus behave just like the built-in units menus. That way you can have just the units that you're interested in shown in menus however you prefer.

Wolfgang's Unitman can be very helpful in customising your calculator for units. See:

But the most useful thing that I know about ALG mode is how to change to RPN mode.


Re: converting units
Message #8 Posted by Brady Wilson on 9 Sept 2004, 11:53 a.m.,
in response to message #2 by Vieira, Luiz C. (Brazil)

Thanks Luiz! I was able to figure it out with your help!

My pleasure d8^) N.T.
Message #9 Posted by Vieira, Luiz C. (Brazil) on 9 Sept 2004, 12:45 p.m.,
in response to message #8 by Brady Wilson

123456 to remove

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