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I really wish it went a bit further into why a programmable RPN calculator is better than an iPhone app or whatever. Explain why RPN is so much better than inf

I really wish it went a bit further into why a programmable RPN calculator is better than an iPhone app or whatever. Explain why RPN is so much better than infix. Explain why the simple, distraction-free BASIC impl is so liberating for certain kinds of tasks. Explain what kinds of tasks this little gizmo enables and why are these tasks better on the gizmo than on a more "modern" alternative. Riff on the weeks of battery-use, the lack of push notifications, the cool retro factor...any of this to convey the coolness that is the gizmo. Nice little one-off piece, but I'd love to see something similar with more passion and explanation!

taeric 9y ago
To be fair, for this dev the reason it is better is it makes them happy. I'm similar. I have my HP 49G sitting on the desk near me. Don't use it much, which makes me sad. I have several things I like more about RPN. Especially over infix, it is a bit easier for me to decompose what I'm doing. Especially since I can't stand the arrow keys to jump around the bloody equation as I'm entering it. That said, I don't think it is "de facto" superior. I do like it, though.
hsnewman 9y ago
From the DM website: Compact size - are small enough to easily fit in any shirt pocket or purse or school backpack Extended battery life - have low power requirements, a single CR2032 will last for many years Full-sized capabilities - have all of the mathematical functions and programming power of full-sized HP calculators Connectivity - have an USB connection to save and load the complete state of the calculator including all programs and registers Firmware update - can be updated to the latest firmware release through the miniUSB connection Nostalgia - give you the feeling you had decades ago
tobyjsullivan 9y ago
The article links to this explanation of RPN and its benefits. https://www.swissmicros.com/what_is_rpn.php https://www.swissmicros.com/what_is_rpn.php After reading, I discovered the macOS calculator supports RPN (Cmd+R) and it is about as cool as described. Looks like the iPhone calculator does not but I'm sure there are great apps.
- tzs 9y ago
  For iPhone, PCalc [1] is quite good. It's also excellent on iPad. In fact, when my iPad 3 was due for replacement, PCalc almost persuaded me to go with iPad Pro instead of switching to a Surface Pro 4, but the SP4 won for better web browsing, better copy/paste, and OneNote. The MacOS calculator's RPN mode is annoying. They don't get stack lifting right. Suppose you want to compute sqrt(12) + pi. Starting from an empty stack, this will do it on an HP calcualtor, PCalc, both RPN calculators I downloaded from the Windows Store, and, well, pretty much every RPN calculator I've used except from Apple: 1 2 SQRT Pi + When you hit the Pi key, it pushes Pi onto the stack, lifting up the sqrt(12) that is already there. On the MacOS calculator, the Pi overwrites the sqrt(12). If you do it this way: 1 2 SQRT 3 . 1 4 1 6 + then it works the same everywhere. One other difference to watch out for. On some calculators, this: 2 ENTER + will give 4. This includes some HP calculators, such as the HP-15C. On these calculators the ENTER pushes whatever is in X, and leaves a copy in X with a flag set telling it that if you enter more digits they should overwrite X. Number entry goes directly into X, so the "2" goes into X, the ENTER pushes X to Y, so now X = 2 and Y = 2. So "+" works, giving 4. On others, it will give a missing operand error. This includes the HP-48 family. On these calculators, number entry does not take place in X. It takes place in some sort of input buffer, and ENTER pushes that onto the stack so it ends up in X. So the "2" goes into the input buffer, ENTER signifies you've finished and 2 goes to X. X was empty before so nothing gets pushed to Y. So you've only got one operand and the "+" fails. (On these calculators, operators other than ENTER implicitly insert an ENTER first if the input buffer is not empty). I'm not sure why HP changed this. The older calculators only had 4 stack positions, no entry buffer, and the display only showed X. By the time of the HP-48 they had many many more stack positions, an entry buffer, and the display could show the bottom 4 stack positions (or the bottom 3 and the entry buffer during digit entry). Perhaps the HP-48 behavior is what they always wanted, but decided it would be too confusing on the older calculators where your visibility was limited. PCalc and MacOS calculator are like the HP-15C. PCalc has an "HP 48 Style" option on the advanced settings page if you prefer the HP-48 behavior. [1] http://www.pcalc.com/ http://www.pcalc.com/
- Fwirt 9y ago
  The firmware for the DM42 is based on GPL'd software available for all major operating systems (including iOS.) http://thomasokken.com/free42/ http://thomasokken.com/free42/
y03a 9y ago
To me, not having to hit the home button, swipe, enter pin, find app, tap app, wait for an animation all before I can do anything the app is supposed to do, and then have to do most of that all over again if I don't touch it for a minute, is an excellent reason for a purpose-built device. Also, fucking buttons. I love buttons. Touch screens are awful.
- ehnto 9y ago
  I can't argue against the general purpose utility of a touchscreen, but I find touchscreens and the software we have built for them to be really cumbersome. For one, buttons on a calculator won't move on me at uncertain points during interaction! Doing things on smartphones is rarely succinct either as you illustrated. But I also find excuses to put switches and dials on things and am the kind of person to think screen based aircraft cockpits are a regression.
  - y03a 9y ago
    I like touchscreen devices for infrequent input interactions. If my screen is already unlocked and the app I need is already open, for consumption based applications like article reading and video watching, it's great. But as soon as I get an on-screen keyboard, I end up frustrated very quickly.
mschaef 9y ago
> Explain why RPN is so much better than infix. At least in my experience, it allows easier reuse of previous values. This makes RPN based calculators easier to use for exploratory kinds of work.
- Steve44 9y ago
  On my PC desktop I use an RPN calculator, I find it so much more useful than a standard style calculator. I think it's because you can see the stack and visually validate the numbers you are working on. I use RPN Calculator v1.3 by Bill Menees, I find the interface a lot cleaner that the others I've tried.

taeric 9y ago

To be fair, for this dev the reason it is better is it makes them happy. I'm similar. I have my HP 49G sitting on the desk near me. Don't use it much, which makes me sad. I have several things I like more about RPN. Especially over infix, it is a bit easier for me to decompose what I'm doing. Especially since I can't stand the arrow keys to jump around the bloody equation as I'm entering it. That said, I don't think it is "de facto" superior. I do like it, though.

hsnewman 9y ago

From the DM website: Compact size - are small enough to easily fit in any shirt pocket or purse or school backpack Extended battery life - have low power requirements, a single CR2032 will last for many years Full-sized capabilities - have all of the mathematical functions and programming power of full-sized HP calculators Connectivity - have an USB connection to save and load the complete state of the calculator including all programs and registers Firmware update - can be updated to the latest firmware release through the miniUSB connection Nostalgia - give you the feeling you had decades ago

tobyjsullivan 9y ago

The article links to this explanation of RPN and its benefits. https://www.swissmicros.com/what_is_rpn.php https://www.swissmicros.com/what_is_rpn.php After reading, I discovered the macOS calculator supports RPN (Cmd+R) and it is about as cool as described. Looks like the iPhone calculator does not but I'm sure there are great apps.

tzs 9y ago
For iPhone, PCalc [1] is quite good. It's also excellent on iPad. In fact, when my iPad 3 was due for replacement, PCalc almost persuaded me to go with iPad Pro instead of switching to a Surface Pro 4, but the SP4 won for better web browsing, better copy/paste, and OneNote. The MacOS calculator's RPN mode is annoying. They don't get stack lifting right. Suppose you want to compute sqrt(12) + pi. Starting from an empty stack, this will do it on an HP calcualtor, PCalc, both RPN calculators I downloaded from the Windows Store, and, well, pretty much every RPN calculator I've used except from Apple: 1 2 SQRT Pi + When you hit the Pi key, it pushes Pi onto the stack, lifting up the sqrt(12) that is already there. On the MacOS calculator, the Pi overwrites the sqrt(12). If you do it this way: 1 2 SQRT 3 . 1 4 1 6 + then it works the same everywhere. One other difference to watch out for. On some calculators, this: 2 ENTER + will give 4. This includes some HP calculators, such as the HP-15C. On these calculators the ENTER pushes whatever is in X, and leaves a copy in X with a flag set telling it that if you enter more digits they should overwrite X. Number entry goes directly into X, so the "2" goes into X, the ENTER pushes X to Y, so now X = 2 and Y = 2. So "+" works, giving 4. On others, it will give a missing operand error. This includes the HP-48 family. On these calculators, number entry does not take place in X. It takes place in some sort of input buffer, and ENTER pushes that onto the stack so it ends up in X. So the "2" goes into the input buffer, ENTER signifies you've finished and 2 goes to X. X was empty before so nothing gets pushed to Y. So you've only got one operand and the "+" fails. (On these calculators, operators other than ENTER implicitly insert an ENTER first if the input buffer is not empty). I'm not sure why HP changed this. The older calculators only had 4 stack positions, no entry buffer, and the display only showed X. By the time of the HP-48 they had many many more stack positions, an entry buffer, and the display could show the bottom 4 stack positions (or the bottom 3 and the entry buffer during digit entry). Perhaps the HP-48 behavior is what they always wanted, but decided it would be too confusing on the older calculators where your visibility was limited. PCalc and MacOS calculator are like the HP-15C. PCalc has an "HP 48 Style" option on the advanced settings page if you prefer the HP-48 behavior. [1] http://www.pcalc.com/ http://www.pcalc.com/
Fwirt 9y ago
The firmware for the DM42 is based on GPL'd software available for all major operating systems (including iOS.) http://thomasokken.com/free42/ http://thomasokken.com/free42/

y03a 9y ago

To me, not having to hit the home button, swipe, enter pin, find app, tap app, wait for an animation all before I can do anything the app is supposed to do, and then have to do most of that all over again if I don't touch it for a minute, is an excellent reason for a purpose-built device. Also, fucking buttons. I love buttons. Touch screens are awful.

ehnto 9y ago
I can't argue against the general purpose utility of a touchscreen, but I find touchscreens and the software we have built for them to be really cumbersome. For one, buttons on a calculator won't move on me at uncertain points during interaction! Doing things on smartphones is rarely succinct either as you illustrated. But I also find excuses to put switches and dials on things and am the kind of person to think screen based aircraft cockpits are a regression.
- y03a 9y ago
  I like touchscreen devices for infrequent input interactions. If my screen is already unlocked and the app I need is already open, for consumption based applications like article reading and video watching, it's great. But as soon as I get an on-screen keyboard, I end up frustrated very quickly.

mschaef 9y ago

> Explain why RPN is so much better than infix. At least in my experience, it allows easier reuse of previous values. This makes RPN based calculators easier to use for exploratory kinds of work.

Steve44 9y ago
On my PC desktop I use an RPN calculator, I find it so much more useful than a standard style calculator. I think it's because you can see the stack and visually validate the numbers you are working on. I use RPN Calculator v1.3 by Bill Menees, I find the interface a lot cleaner that the others I've tried.