First Month with 50g

[MarkMason]

[font=Arial]Received the 50g about 5 weeks ago. I bought it as a retirement toy. Had I still been a working engineer I would probably have gone with a WP-34s or 35s, but wanted something different. The 50g’s RPL appealed by allowing both stack based RPN style programming as well as Algebraic expression evaluation in programs for readability. I have found the 50g to be insanely capable, RPL to be involved to learn but logical and powerful, and the whole package lots and lots of fun !!! Prior to its arrival I worked on the emulator which is a very nice option to have, but after using the mouse to actuate the keys it gave me a new appreciation for the physical calculator.

On the first day after opening the package the 50g felt light, ‘plastic-ey’, and with an awkwardly placed [Enter] key. By the third day everything became ‘normal’ and has felt so since. I’ve enjoyed reading through the HP User’s Guide and working through all the examples (in RPN). The User’s Manual seems to be a subset of the User’s Guide so I’ve not bothered with it. Eduardo Kalinowski’s Programming in UserRPL was great, the exercises were good practice. The HP Museum USB arrived and I’ve already devoured W. Wickes HP41/48 Transitions, which I found just as satisfying and informative as the recommendations on this forum indicated. Right now I’m half way through his first Insights book. BTW, thanks David for putting together this USB repository for such a nominally small price. Just the forum archives are enough for months of amusement, and the manuals are a great reference. Special thanks to Bill Markwick for the ultra-useful HLP49, which I’ve come to rely on as a daily reference.

So far User RPL has been fun to play with. I have discovered that algebraic expressions inside a program bring with them an execution speed disadvantage vs stack based commands and functions. At least we have a choice. I’m even getting used to how far postscript notation is taken, ‘a’ STO, a b >, etc. One thing that has struck me as a little opposite to stack logic is defining local variables in a program. The convention here seems to have been arranged to be read left to right, with values and variables both in left to right order. If your values are already on the stack, this seems to execute backwards:

Stack:
3: 7
2: 6
1: 5

<< -> a b c <<……>>..>>
Leaves a=7, b=6, and c=5, whereas:

<< ‘a’ STO ‘b’ STO ‘c’ STO
Would leave a=5, b=6, and c=7

In the second example, the first variable encountered logically takes its value from level 1 of the stack. In the first example the first variable listed in the program jumps to level 3 to take its value. This convention seems like an exception, but if there are not too many of these I can just commit it to memory and go on.

Using the Space key instead of Enter to separate a series of numbers in the command line is very slick. Seeing all the values jump to their own levels of the stack upon pressing Enter always makes me smile.

Storing a variable seems to take me more steps than in the User’s Guide. My keystrokes are normally: [tick] [alpha] [alpha] name chars [K] [Backspace ()] [alpha] [Enter] [STO]. With a little more practice my goal is to reduce this by at least three!! :~)

I’ve been using NiMH AAA cells, which seem to run the calculator OK but don’t last very long. Been through 2 sets so far, but judging from how quickly they recharge, I strongly suspect that the reduced voltage output (1.2vdc vs 1.5vdc for alkaline cells) translates into the calculator not using their full charge. This is not a problem for me as a few years ago I discovered Eneloops and converted all devices that take AA and AAA cells to these and have charged sets on hand ready for rotation. Also the USB power option a nice backup.

Mark

[Han]

I don't remember, but does the USB port also charge the batteries?

Quote:Storing a variable seems to take me more steps than in the User’s Guide. My keystrokes are normally: [tick] [alpha] [alpha] name chars [K] [Backspace ()] [alpha] [Enter] [STO]. With a little more practice my goal is to reduce this by at least three!! :~)

If the variable does not exist yet, then you can simply type its name (no tic marks needed) and the name is automatically parsed to have the tic marks. If the variable does exist, then it will likely appear in the variable menu, accessible via the VAR key. You can then store to an existing variable using a shift key followed by the corresponding F? key (1 through 6). The other shift key + the corresponding soft key will recall the contents of that variable (I forget which shift does which). One thing to watch out for is the "long hold" feature (which I personally hate) for keypresses. You may also want to read up on the ->KEYTIME command if you type really fast (I set mine to about 100 since I am a "two-thumb-typer" when using calculators).

[Tugdual]

Glad to see another 50g thread starting here. I'm going through the same discovery steps at the moment and had many questions which I compiled in one thread to avoid flooding the forum and the community has always been very helpful.
I found your comment about stack and local variables interesting. Never thought about that before but hell you're right and I may find myself confused now .
I just started with AAA batteries and having read some other threads on this topic it seems that the 50g is indicating low battery around 4.8V which is a bit high for average 1.2V battery cells. So quite probably only very little power is consumed and quite certainly the 50g was not intended to be used with rechargeable batteries. Wonder if we can soft adjust the warning level ?

@Han
I don't think USB is charging batteries it would be dangerous with normal batteries.

[Voldemar]

I also started to learn the hp 50g. I bought it last month. Very exciting.

[Voldemar]

(04-09-2015 03:49 AM)Han Wrote:  The other shift key + the corresponding soft key will recall the contents of that variable (I forget which shift does which).

If variable exists, VAR key and soft key for recall variable. There is no need to press right shift key before recalling variable with soft key.

[Thomas Radtke]

(04-09-2015 06:54 AM)Voldemar Wrote:  There is no need to press right shift key before recalling variable with soft key.

If the variable contains a program, just pressing the softkey will run it instead of editing it (on the 48, but I guess it's the same on a 50g).

[Voldemar]

[/quote]
If the variable contains a program, just pressing the softkey will run it instead of editing it (on the 48, but I guess it's the same on a 50g).
[/quote]
Yes. It is true.

[Gilles]

(04-09-2015 03:32 AM)MarkMason Wrote:  Stack:
3: 7
2: 6
1: 5

<< -> a b c <<……>>..>>
Leaves a=7, b=6, and c=5, whereas:

<< ‘a’ STO ‘b’ STO ‘c’ STO
Would leave a=5, b=6, and c=7

In the second example, the first variable encountered logically takes its value from level 1 of the stack.
Mark

Note that with your example you can do :

{ 'a' 'b' 'c' } STO

Leaves a=7, b=6, and c=5

[Voldemar]

(04-09-2015 07:38 AM)Gilles Wrote:  Note that with your example you can do :

{ 'a' 'b' 'c' } STO

Leaves a=7, b=6, and c=5

{7 6 5}
ENTER
{'A''B''C'}
ENTER
STO

[MarkMason]

(04-09-2015 08:30 AM)Voldemar Wrote:  

(04-09-2015 07:38 AM)Gilles Wrote:  Note that with your example you can do :

{ 'a' 'b' 'c' } STO

Leaves a=7, b=6, and c=5

{7 6 5}
ENTER
{'A''B''C'}
ENTER
STO

Cool, never thought of using lists!!!! Thanks.

So far I'm using local variables 'as is', even though it is still strikes me as backwards.

Mark

[MarkMason]

(04-09-2015 03:49 AM)Han Wrote:  I don't remember, but does the USB port also charge the batteries?

Quote:Storing a variable seems to take me more steps than in the User’s Guide. My keystrokes are normally: [tick] [alpha] [alpha] name chars [K] [Backspace ()] [alpha] [Enter] [STO]. With a little more practice my goal is to reduce this by at least three!! :~)

If the variable does not exist yet, then you can simply type its name (no tic marks needed) and the name is automatically parsed to have the tic marks. If the variable does exist, then it will likely appear in the variable menu, accessible via the VAR key. You can then store to an existing variable using a shift key followed by the corresponding F? key (1 through 6). The other shift key + the corresponding soft key will recall the contents of that variable (I forget which shift does which). One thing to watch out for is the "long hold" feature (which I personally hate) for keypresses. You may also want to read up on the ->KEYTIME command if you type really fast (I set mine to about 100 since I am a "two-thumb-typer" when using calculators).

Han,

Thanks for the input. When reading your message it occurred to me that not using the tick marks is actually a test to see if the variable exists in the current directory path. This looks like a good practice.

That particular paragraph of my first post was mainly to relate that even after 5 weeks I still can't remember to cancel the alpha key before using a function. I've decided that if I get into the habit of using [Enter] after typing in the variable name the alpha mode automatically cancels, and [STO] works (without going through the letter K unintended entry).

When working with programs I find the right/left shift + variable keys quite handy. I do pause every time to remember that the white key (left shift) is the one that replaces the variable contents with level 1 of the stack. So far I've only overwritten one program unintentionally by getting this wrong. Being able to save and recall this way really facilitates writing programs in stages and debugging.

This past weekend I was visiting my son when the low battery warning icon came on. I plugged the 50g into the laptop's hot USB port and left it all night. The next morning the low battery warning was still on, so I concluded that the USB cable does not charge the batteries, which is good with NiMH as they need a 'smart' charger.

Thanks for the input,

Mark

[rprosperi]

Welcome to RPL, a lovely place to explore. Be sure to check out the enormous collection of RPL stuff at hpcalc.org

(04-09-2015 03:32 AM)MarkMason Wrote:  My keystrokes are normally: [tick] [alpha] [alpha] name chars [K] [Backspace ()] [alpha] [Enter] [STO]. With a little more practice my goal is to reduce this by at least three!! :~)

One tiny thing that saves keys is to set flag 60 to make a single [alpha] press lock Apha-mode on. I felt silly for not having thought of it when Joe pointed this out to me; you nearly always are typing more than 1 letter when using alpha mode, so doing this saves a keystroke every time.

[Brad Barton]

(04-09-2015 01:04 PM)MarkMason Wrote:  When working with programs I find the right/left shift + variable keys quite handy. I do pause every time to remember that the white key (left shift) is the one that replaces the variable contents with level 1 of the stack. So far I've only overwritten one program unintentionally by getting this wrong. Being able to save and recall this way really facilitates writing programs in stages and debugging.

I find it easier to remember which shift key to use if I mentally picture all objects as being stored in a physical location to the upper left of the calculator. If I use left-shift, I'm storing the variable to that "location", and if I use right-shift, the variable's contents get "pulled to the right" onto the stack.

Sounds like a silly way to remember it, but it works for me.

Brad

[walter b]

Quite a nice idea. We call such a method "Eselsbrücke" (seems to be called "mnemonic" in your language).

d:-)

[MarkMason]

(04-09-2015 01:53 PM)rprosperi Wrote:  Welcome to RPL, a lovely place to explore. Be sure to check out the enormous collection of RPL stuff at hpcalc.org

One tiny thing that saves keys is to set flag 60 to make a single [alpha] press lock Apha-mode on. I felt silly for not having thought of it when Joe pointed this out to me; you nearly always are typing more than 1 letter when using alpha mode, so doing this saves a keystroke every time.

Bob,

Thanks for the tip, I'll try flag -60 next. It's things like this that add up to a smoother experience.

As for RPL, I believe I'm firmly in the UserRPL camp. I like it and hope to see it live on in some form in the HP Prime or Prime follow-on (HP Primate?). With 2300+ functions it will take a long time to learn enough to be able to interpret programs, but that's part of the fun.

One feature that may be in the 'nice to have' category would be a RPN sequence to algebraic expression converter. I really haven't decided if this is realistic or necessary but the calculator does so many other incredible things like symbolic math it makes one's mind wander....

Thanks,

Mark

[Joe Horn]

(04-10-2015 12:45 AM)MarkMason Wrote:  One feature that may be in the 'nice to have' category would be a RPN sequence to algebraic expression converter. I really haven't decided if this is realistic or necessary but the calculator does so many other incredible things like symbolic math it makes one's mind wander....

The 50g has an RPN-to-algebraic converter (and vice versa) built in. Just type 256 MENU and then press NXT. The last two menu keys are →LST and →ALG. They convert an algebraic object to RPN (in list form), and RPN (in list form) to algebraic object, respectively:

'1+2*3' →LST --> { 1 2 3 * + }
{ 1 2 3 * + } →ALG --> '1+2*3'

Cool, huh? WARNING: Be careful not to throw bad RPN at →ALG, or you'll either get an 'Invalid Expression' (do NOT evaluate these!) or a "Try To Restore Memory?" followed by a memory wipe. An example of bad RPN would be { 1 2 3 + } because that doesn't resolve to a single object. { 1 2 + * } is likewise bad.

[MarkMason]

(04-09-2015 08:15 PM)Brad Barton Wrote:  I find it easier to remember which shift key to use if I mentally picture all objects as being stored in a physical location to the upper left of the calculator. If I use left-shift, I'm storing the variable to that "location", and if I use right-shift, the variable's contents get "pulled to the right" onto the stack.

Sounds like a silly way to remember it, but it works for me.

Brad

Brad,

My word for this is 'genius' !!!!! Thanks for sharing

Bob,

Tried flag -60 and love it. Thanks for the tip. I also found out that both Enter and On cancel the alpha as well as the lower case alpha mode. I did have some confusion when using lower case alpha lock, then getting out of alpha by one press of the [Alpha] key. The next alpha lock resulted in lower case text. Being able to reset both is quite useful.

Had this response all ready last night then we lost power due to a thunderstorm. A night without internet..........

Cheers,

Mark

[Omar Deen]

(04-10-2015 12:45 AM)MarkMason Wrote:  [quote='rprosperi' pid='32473' dateline='1428587594']
Welcome to RPL, a lovely place to explore. Be sure to check out the enormous collection of RPL stuff at hpcalc.org


As for RPL, I believe I'm firmly in the UserRPL camp. I like it and hope to see it live on in some form in the HP Prime or Prime follow-on (HP Primate?). With 2300+ functions it will take a long time to learn enough to be able to interpret programs, but that's part of the fun.

One feature that may be in the 'nice to have' category would be a RPN sequence to algebraic expression converter. I really haven't decided if this is realistic or necessary but the calculator does so many other incredible things like symbolic math it makes one's mind wander....

Thanks,

Mark

For me, I've been able to program my calculator with formulas, tables and equation converting my calculator into a true Shop calculator that is 100% better than those ready made specific trade calculators that are sold by company Z . I wouldn't be able to do it without the programming resources that HP users have contributed to several websites. And also countless answered questions from users such as Joe, Andreas, Han .... they are too many to name.

Learning to get the Max out of your calculator do take some time however, they are an abundance of resource to make the transition smooth

Omar

[rogeriol]

(04-09-2015 03:32 AM)MarkMason Wrote:  [font=Arial]Received the 50g about 5 weeks ago. I bought it as a retirement toy. Had I still been a working engineer I would probably have gone with a WP-34s or 35s, but wanted
...
Mark

Funny. I got my first RPL calculator in 1990 (28S) also as a toy and I fumbled a lot with the programming language, it was a sensation at the time, imagine a calculator that can do symbolic math.
It was a great incentive to follow the TI career, however it was not the first 'computer' I had. Programming wise it was very fun. In a time with no Internet for the masses and no information at all about the device except the manual (excellent BTW).

And you got it as a retirement toy.

[Tugdual]

(04-12-2015 03:41 AM)Omar Deen Wrote:  For me, I've been able to program my calculator with formulas, tables and equation converting my calculator into a true Shop calculator that is 100% better than those ready made specific trade calculators that are sold by company Z . I wouldn't be able to do it without the programming resources that HP users have contributed to several websites. And also countless answered questions from users such as Joe, Andreas, Han .... they are too many to name.

Learning to get the Max out of your calculator do take some time however, they are an abundance of resource to make the transition smooth

Omar

I wonder what 50g owners are doing with their machines for professional purposes. I purchased one for a hobby (I never had seen RPL before) and a very few manual calculations (price calculations most of the time...) at work. When things become serious, most people would switch on Excel and myself on C++.
Anything I do on the 50g is good fun but terribly inefficient. For my day to day work, a 35S is actually the best option, not the 50G. So I would be interested in some feedback from users regarding their professional use of the calculator (anything not related to education).