
#73
Aug1707, 09:27 PM

P: 3

NO. Do you understand that x^4, as written, actually stands for 1*x^4. Go look at an actual mathematics book for reference. So, follow the order of operations; take the four power first, then multiply by 1. If you would like, consult ANY standard algebra text. Wikipedia is not an accepted scientific or mathematical reference, the last time I checked. When it is acceptable to quote from Wikipedia in referred papers, I'll reconsider my stand on this. I don't consider Fortran to be a final arbiter in this matter, as it was designed for engineers. It also doesn't matter what programming language or brand of calculator does what. I am sure that they all account for their operations. Again, okay if defined up front. Really, I thought we were talking of the only order of operations that is widely accepted among all Mathematicians when one is taling about the RING of real numbers. Wouldn't want to argue with your boss. However, I actually have a bachelors degree and masters degree in Mathematics, the actual subject being discussed. I think I am qualified to speak on this topic. I don't think physics and engineering majors quite get into the foundations of Mathematics. 



#74
Aug2307, 02:23 PM

P: 2

2^4=(2)(2)(2)(2)=
Anyone??? This may be a long day 



#75
Aug2307, 03:58 PM

HW Helper
P: 2,693

 2^4 \] [/tex] indicates the negative of two to the fourth power; note no grouping symbols, so you do the exponentiation first. [tex] \[  2^4 =  (2)(2)(2)(2) \] [/tex] 



#76
Aug2307, 04:15 PM

P: 2

I thought this was all just levity from all those involved........
The original was (2)^4 way back in post #13 Please move on from this. I found this forum looking for info about the HP 50g as my 48 has gone bad. If anyone has more of the good, the bad and the ugly of the new flavor I would like to here from you. My degree is in ARTHEYALLINSANEORISITME 



#77
Aug2607, 05:20 PM

P: 117

Hey everyone, I've been trying to install the RPN program on my Ti89 Titanium, and everytime I try to run it, the calculator freezes and I am forced to reset, anyone want to help me through this?




#78
Sep1807, 10:01 PM

P: 1,113

Ti89 Ftw




#79
Sep1907, 01:27 PM

P: 340

Well, I personally use the TiVoyage 200. Its the most advanced thing Ti has got on the market. Thats your best bet for having the functions you want.




#80
Oct307, 06:05 PM

P: 1

Well, I'm coming into the thread very late, but have a funny anecdote that might be worth sharing. Full disclosure: I've been an HP calculator fanatic for almost 20 years now and think RPN is the coolest thing since sliced bread, LOL.
Last year, I taught an undergrad class for the first time and had 37 junior and senior engineering students. Every single one of them used a TI[whatever] and not a single one had an HP. Anyway, on their second exam, they had to solve an equation that took an entire line to write and had three square roots, two of them nested. As I graded it, I noticed that almost every single one of them screwed up punching it through their calculator. Turns out that 3/37 were able to do it without a mistake. Most of them were writing it out in 23 lines, etc. I knew I'd catch grief over that, so I punched it through using my HP48G calculator, which is of course RPL (like RPN). I did it three times in a row without an error, averaging 22 sec.!! Of course, I had that ready for them the next class, LOL. Granted, I was using my calculator when most of them were in preschool, but supposedly younger folks are better at newfangled gadgets, right? It's hard to explain to nonRPN users why RPN is better, but it really is. I've never met anybody who gave it a fair try for 23 weeks who didn't switch over. 



#81
Oct1607, 11:50 PM

P: 20

I agree. I have the hp 50g and am very happy with it, once I went rpn, I never went back.
Well, I did at times when the 50g's symbolic solving didn't sit so well with the professors, but honestly, it's one of the best investments I've ever made. I'd recommend it for people going into engineering. 



#82
Oct2307, 02:48 AM

P: 10

I've been using HP's for the last zillion years (or at least since the first HP 35). RPN, when I first met it was confusing but after 10 minutes or so playing with it, it made complete sense to me and I found it easy to use. I have been using HP calculators ever since. Despite my moniker, I'm a professional engineer and would not be without one.
The HP50g is my latest (the last, an HP48sx died on me last year after 20 years of faithful service) and so far the best calculator I have used. If you like algebraic input, it does have it. Indeed the user manual gives many more examples on how to use algebraic mode than it gives for RPN mode. My only complaint is that the user manual only brushes the surface of what it can do. The user manual that comes with the machine is some 880 pages long. You can write some very sophisticated programmes using the built in RPL language but you must know RPN and how the stack operates to use it efficiently. The ten or fifteen minutes you spend learning RPN is a real investment. Once you know how to use it, you'll never regret it! 



#83
Oct2307, 08:20 AM

Sci Advisor
P: 2,283





#84
Oct3007, 08:37 PM

P: 2

IF you think the minus is part of the number (2) you solve with: 2 +/ ENTER 4 y^x ...and get 16 BUT if you decide the  is an operation, and to be done last, you enter: 2 ENTER 4 y^x +/ ...and get 16 The RPN makes no assumptions, it's up to YOU to enter the equation correctly. Whereas the TI made an assumption which sparked this lively debate. While reading past posts, for some reason I kept thinking of the infamous question  the airspeed of an unladen swallow. African or European ? (24 mph for European... http://www.style.org/unladenswallow/ ) 



#85
Nov507, 02:39 PM

P: 1





#86
Nov507, 05:10 PM

P: 2

Without that key, the act of creating a ve number is harder. If (2) = (1)(2) then how do you enter (1)? The RPN would be: 0 ENTER 1  * In an effort to keep the thread moving which keyboard do you prefer? I've heard people moan about the "feel" of keys, but I also mean the actual LAYOUT. I sure do miss the doublewidth ENTER key. Personally, I'd prefer the ON and ALPHA keys be above the actual LCD, similar to my old favorite the HP41 series. And the 4way navigation buttons, while nice, take up too much keyboard space. Comments? Suggestions? Comparisons to TI89 ? 



#87
Dec207, 08:55 PM

P: 163

I've been a pretty big fan of the older HP calculators (meaning, up the HP 48 series). Many of the examples above explaining why RPN is better don't really capture why RPN truly is a better input method. Forget using nice, whole numbers. In the real world, the numbers we use are almost never that nice.
Suppose you need to work with the quantity, say, x=1.91872163435 (just made this up), and this number appears in your calculations more than once. To speed up entry AND to reduce the possibility of a typo when reentering the quantity 'x', you may actually want to store this number in the variable 'x'. This takes a few extra keystrokes to do on most algebraicentry machines, such as the TI89. On an RPN machine, you would simply enter the number once, and DUP (duplicate) it however many times you need to use the number. Say I want to compute [(3*x+5)^(x1)]/[(2+7.11)^(3/4)1], you'd not only have to store the number 1.91872163435 into 'x' (again, to reduce error in inputting and save time), you would also need to close the parentheses in the proper manner so as to not cause problems with the order of operations. On a machine such as the HP48GX, presumably already be in the STACK menu (the '>' means the right arrow, which acts as the SWAP command on the HP48 series): 1.91872163435 ENTER ENTER 3 * 5 + > 1  ^ 2 7.11 + 3 4 / ^ 1  / There is no need for parentheses. There is an added benefit, which many students often take for granted. RPN entry reinforces the order of operations. It is quite sad to see so many undergraduate students fail exams because they still have not mastered the order of operations. Even worse, many students don't realize why their calculator "gives them the wrong answers." RPN essentially forces you to know the rules. Also, the newer HP50G has both RPN and algebraic entry builtin. Even the older HP48 series had both methods of entry (with algebraic entry requiring exactly one more key, the 'tic' mark, than any TI product). 



#88
Dec207, 09:08 PM

P: 163

The TI's distinguis "negative" from "minus"  this is truly detrimental to students who need to master the order of operations. By using a smaller hyphen for negative, and a longer hyphen for subtraction, the TI's are creating ambiguity for those who are unable to clearly distinguish the lengths of these hyphens. Moreover, they are encouraging poor notation, as students think it's ok to have "2^4 = 16" because 1) their calculator seems do say so and 2) they can't see the difference between the "negative" hyphen and "minus" hyphen. 



#89
Dec207, 09:25 PM

P: 163

Imagine entering in the a and b values separately. If these were your only inputs, how would you compute this using RPN? With a stack, you'd see: 2: a 1: b First DUP the value b (we'll use it later for dividing) to get: 3: a 2: b 1: b Then ROT (rotate) the a value to get: 3: b 2: b 1: a Then + to add, and / to get (a+b)/b. Thus, to compute (a+b)/b, you would simply do: << DUP ROT + / >> Store this as a variable, and it then becomes part of the variables menu. From this point on, you just enter in your a value, your b value, and press the variable menu key corresponding to your short program. As another example, if you want to, say, add 10 numbers, you'd simply need: << + + + + + + + + + >> Then you just input 10 numbers (enter all ten separated with space, if you wish) and then press the menu key corresponding to the variable under which you stored the program above. In sum, the way you enter and compute using RPN converts directly into programs with little to no effort. 



#90
Dec207, 09:40 PM

P: 163




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