33s or 35s or casio fx-5800 for electronic engineering


Hi all. I am an electronic engineer (soon I hope) and I need a programmable (but not graphical) calculator. I have read about them and I think that I have those three options.
Is 35s a bad product? is it true that 33s is faster than 35s but 35s is more powerful for programming? And what about fx-5800? It has the same amount of memory, 4 line display and a language similar to basic but, has it got some lacks?
Also I hope that I could use the calculator in the future.

Thanks all.


fx-5800p? what is this. can't find a lot about it out there, some sales in Germany only and a few on ebay from Korea.

does anyone know more about it. the screen looks nice. looks like it uses casios weird programming notation. i hope it's not too modal (the curse of casio). maybe i should get one and check it out?



might be a follow up to the 4800p,



Interesting info here:

Casio FX-5800p Page


Edited: 21 Mar 2010, 12:12 p.m.


I compare fx-5800p and hp 35s because, If we do not copare them with discontinued products, they are the most advanced programmable (not graphical) calculators from casio and hp.

About the fx-5800



Some specs:




I am undecided. Hp 35s has RPN and its pretty complete, but fx-5800p is faster according to http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/articles.cgi?read=700

And also 33s is faster than the others but I cannot do gto to a line number.

Calculator Speed Benchmark using the N-Queens Problem

4:17 HP-35S Keystroke / RPN

3:47 FX-5800P Formula / Array

2:11 HP-33S Keystroke / RPN

Edited: 21 Mar 2010, 12:26 p.m.


Strictly speaking, I believe the (current model) HP-50g to be the most advanced scientific and graphing calculator HP makes. You probably would be best to compare that one against the Casio.




I would only consider RPN personally. I have both 33s and 35s and for day-to-day work the 35s is far preferred - better keyboard, layout, display contrast etc.


Also, it would be fun to see the times using the 30b and the Casio FX-9860g slim (the best Casio in my estimation, and also arguably one of the fastest calculators made).

Anyone up for posting the speeds on the other two above?

Last year we had some discussion of this and Egan posted the speeds for the 71b and 41c. Results Here




Kind of answered my own question. ;-)

I found the master list from 2007 and it appears that the posting is updated by Xerxes regularly. He has times for both the FX-9860g at a blazing 17 SECONDS for N-queens, and the 30b at a shocking 11 SECONDS. Wow. :-)

This 30b is one fast calculator...

Edited: 21 Mar 2010, 2:16 p.m.



yes, the 30b runs at a faster clock rate than the 9860g, base rates are 36Mhz (i think) and 14.7Mhz resp.

However, i've overclocked my 9860 by about 2x :-) There is a 4x option, but it's a bit unstable, but 2x is fine (just uses more power). In my reckon calculator for the 9860g, i temporarily engage the 2x for heavy-duty operations, like integer factorisation and graph plotting.

when i get around to putting a program language in it, i plan to let the user have control over the speed setting - could be very useful.


here is what i'd say at first glance;

firstly, i think your choice is either the 35s or the 5800p.

the casio will be faster and more accurate, integrate and solve are likely to be better (more modern algorithm, + brute force). the screen is bigger, which may be a big plus for matrices if you need them. However, i never had any problem with matrices on the single line 15c, so it's not a dealbreaker, and further it makes the unit physically larger.

casio have their weird programming language which isnt basic and rather odd, although i can see it being ok for small programs. alternatively the 35s is step programmable, which is pretty low level, but useable and also not great for large programs. also, you might have problems using all of the 35s program memory due to labels etc.

casio really missed a trick here not having a standard way to transfer programs to the PC (or am i wrong?) i see it comes with calc-to-calc transfer, but not calc-to-pc transfer. it might be worth seeing if there are some user community tools for calc-to-pc transfer. if this is possible, if it were me, i'd get the casio (im a big fan of cross development) and also it means you can load programs from others without having to type them in - this would be a huge plus!

complex number might work a bit more intuitively on the casio, but i suspect that the support for complex operations is limited to the 4 basic ops, sqrt, 1/x. for example Y^X is probably not supported for complex Y. however, the complex support on the 35s is also a bit lacking (compared to 15c, 48 etc).

however, the biggest overall factor is whether you like the way the machine works. some machines have a habit of being really annoying and some aren't. i cant say if the 5800p is or not. if it's like the 4800p, i think it's ok, but makers have a habit of making simple things complicated and annoying (for example if you press "Sqrt(" then 2, so you have to press ")" as well). if you get the 35s, then you really need to be using it in RPN, so that means you like RPN. If you hate RPN, i would advise the casio conversely if you are big on RPN, get the 35s.

lastly, i presume you don't want graphics for some reason, despite the fact that the 5800 has a large screen, so it's not a size constraint. otherwise there are more calculators to choose from.


As an EE, I'd say the biggest factor is how complex numbers are handled. I find both machines lack behind my 28C/S, or the 15C, for that matter. Otherwise I am quite fond of my 35S. The graphing capabilities are worthless for an engineer (since we have access to more powerful tools), but handy for students. I know my comment is not helpful, but had to give it anyway.


Owning one of each, here are my thoughts.

Of the three the fx-5800 has the most functions. It can do pretty much what the HP:s can and much more. The only thing I can thing of that the HP:s can that the fx-5800 cannot is to take the logarithm of a complex number. But for normal complex calculations the Casio is much easier to use. One problem with all the functions in the fx-5800 though is that many are burried quite deep in menus and requires many keystrokes to get to.

The calculator I enjoy using the most is the 33s. It's RPN, has most functions I need and has a nice feel to the keyboard. Compared to the 33s the 35s adds some nice functions. But I don't like the layout of the keyboard of the 35s and it constantly misses keystrokes if you type too fast. The feeling in the keyboard of the fx-5800 is not good, but at least it does not miss any key strokes.


I love my 35s. In fact it rekindled in me the love of hp calculators and started me collecting them.

I use it all the time as except when I need to work in hex or binary when I use a 32sii.

I really like the solver feature which I hadn't played with much on the 32sii although I have had it for years.

I have to wonder what problems people are doing on a daily basis that they are complaining about the speed of a hand held calculator. For serious stuff I would use MathCad or scilab or even Excel.


I can't speak to the casio, but if you want an HP calculator for engineering, I'd get the 50g, or the 48gII if money is a concern. You will find the CAS system extremely useful when you start getting to complicated equations. Also, you'll want the I/O capabilities so you can easily load programs onto the calculator. With the 35s or 33s, you have to key in the programs by hand, which can be very time consuming.

If you don't need RPN, you might look at the 40gs also.

I own both the 48gII and 50g. To me, the advantages of the 50g are (in order) the SD card, more memory, faster processor, larger display, carrying pouch vs slide-on plastic shell. The 48gII has one advantage over the 50g in my opinion: an easier-to-read keyboard.

A word of warning - if you decide to get the 48gII, be aware that HP made two versions that are quite different. The old version, which is available on ebay for very cheap, has 80k for memory, a serial point only, no equation library etc. The newer ones have serial and USB, 230k of memory, equation library and use 4 batteries. You can tell the difference on the blister pack by looking for the number of batteries and by carefully reading the package to see if it says it supports USB.

A good calculator can make a huge difference when taking tests and doing homework. If you get the right one, you'll use it for decades. I used my HP41CV for 25 years, but I got the card reader attachment very quickly after buying the calculator so I could enter programs easily. Trust me, you NEED I/O.



I think that I will buy the hp 35s for these reasons:

- Casio fx-5800p seems good but it lacks rpn. Also I want to taste an hp calculator (I have always used casio ones).

- I want a lightweight, not very big calculator.

- About 48gII and 50g: They have I/0 and that is very good. However I only need the calculator for a daily use and not for very complex things. I agree with Norman Dziedzic: If I want to do complex things I use Maple or Matlab.

- For my needs, I value simultaneous equation solving, operate with complex numbers, base conversions, and writing moderately complex programs. 35s has those features. 33s does not have built-in simultaneous equation solving (you have to program it and waste some labels) and although it is faster, it cannot gto program line. Also it lacks indirect variables (useful in complex programs).

I will go to bed now. Thanks and see you tommorrow.


Don't expect much from the 35s base conversions. 33s is much better for that.


I would suggest going for a 33s and ignoring the 35s because of its collection of really stupid bugs (base conversions, unusable floating point display, ...). The 35s looks nice but that doesn't help if you can't see the result of a calculation or have to press lots of keys to do some simple calculations with hexadecimal or binary numbers. And if you have to do many calculations with complex numbers - which is very likely in any kind of electrical engineering - than you should go for a HP48, 49 or 50. The 33s and 35s are nearly useless in this area.


In the present context, anything but a computer is essentially a toy, or useful assistance to ad-hoc manual computation.

To that end, the 35s, the Casio, the 33s, old HP RPN machines, are all a crippling disadvantage. I'd steer clear of them if you are young and want to get ahead.

Those of us who are older fondly remember the days when we got our first 11c or 15c, or a bit older, when we got our 34c, 41C, or before that our 55, 65, 67 etc. In those days, when a real programmable computer such as the HP83 cost over $2200, and the Apple and the TRS 80 model II did not yet exist, these programmable calculators were fantastic!

Today, even the programmables, such as our venerable 41C, 42S, 15C, or the newer, more crippled 35S, are avocational curiosities, not effective tools, where programming is concerned. Computation, yes, portability, yes, programming, no.

Don't get me wrong: I own a number of RPN machines including the new ones. I use the 27s frequently for its solver. But I am "old" and therefore make use of legacy equipment because I already know it well and it works for me. But if there is a lot to do, I go to the computer.

Some other posts mention test-taking. This is really the crux of the matter. In your career, you are going to use a real computer to solve real programs. You will buy fantastic software for $1000 that can run circles around everything--circuit analysis, harmonic analysis, you name it. But for tests you need a calculator. To this end, find out what is *permissible* in your university. Find out what is permissible for your licensing examinations. It is likely that the 50G will be the only proper choice, if permitted. IT is *fully* programmable in RPL, SysRPL, Assembly language, and C! (If you like retro, buy a 48G series but you'll need cards and SpeedUI or Metakernel, and ALG48 or Erable for CAS--stuff I don't have expertise in).

In the US, we have to use the 33s or 35s for licensing tests as the 50G and all graphing calcs are banned. In the recent past, everybody used 48S and later 48G series on the tests. This dates all the way back to 1990!

35S has the disadvantages mentioned above: goofy quirky incomplete functional design for non base 10, and polar to rectangular. Trouble with trig close to 90 degrees. Some have problem with non registering keys. This also happens to some 33s. We are picky--we grew up on Voyagers, Spice, Classics, Woodstocks and Pioneers!

35S solver is better than 33s because of full editability of equations. 33S is way better in its layout for doing Base arithmetic, Polar to Rectangular and other stuff. Earlier ROM versions of the 33s had a bug in the Rectangular to Polar, as well as the Decimal Hours to H.MS maths! Only buy a newer one with the bigger decimal point. If you get an old one, you can write short, easy programs to do these functions correctly (I and a number of others here wrote programs that did this and you can find them and check them. At one point HP even made them a service release though I don't know it it is still up on their website).

I hope that helps.

[edited for spelling and grammar]

Edited: 22 Mar 2010, 10:06 p.m. after one or more responses were posted


In the present context, anything but a computer is essentially a toy, or a useful assistance to ad-hoc manual computation.

To that end, the 35s, the Casio, the 33s, old HP RPN machines, are all a crippling disadvantage. I'd steer clear of them if you are young and want to get ahead...

Today, even the programmables, such as our venerable 41C, 42S, 15C, or the newer, more crippled 35S, are avocational curiosities, not effective tools, where programming is concerned. Computation, yes, portability, yes, programming, no...

I use the 27s frequently for its solver...

Bill, if you hadn't posted this so late, so that not many will see it, you would have started another big debate.

Of course I disagree, because I consider writing Solver routines programming, and those are a boon to me in my work. As far as keystroke programming, well, I hardly ever do it myself, so I can't disagree on the practicality, but I do disagree on the power available there.

I think perhaps what you are really saying is for the young engineer starting out, don't bother trying to learn programming calculators, because you will really use computers for almost everything...



I think perhaps what you are really saying is for the young engineer starting out, don't bother trying to learn programming calculators, because you will really use computers for almost everything...

Yep. And why waste effort with no I/O (42s, 27s 15c, 35s etc)? If it is ad-hoc, so what, but for real work, that's crazy.


If it is ad-hoc, so what, but for real work, that's crazy.

I recently had a real work problem that I could not find a ready solution via computer programs, but I found a HP 48 program that would solve it!


...and that is the great thing about the 48 (including the 49 and 50): it has a lot available, and it has I/O, and it can be run as an emulator on the computer, and you can take the files back and forth from the real thing to the computer. Really it is the holy grail of calculators....even though I am a rank beginner on the 48, I see its merits!

Edited: 23 Mar 2010, 7:59 p.m.


A lot of good points, but I too disagree. Maybe it's not such a help in electrical engineering, but I can tell you that in computer science -- as a software developer -- having a calculator handy can be a big help. It's a daily event.

When I have 20 windows open on my computer, and things are already slow enough, the last thing I want to do is open a copy of Free42 or other program and wait for it to launch.

In fact, on a day-to-day basis, I actually have an HP-97 sitting on my desk. I get a lot of laughs and smirks, but when I have a group sitting in my office working out some simple math problem, I'm at the answer far faster than anyone in my area. That, IMHO, is valuable.




Hi Bruce,

When I have 20 windows open on my computer, and things are already slow enough, the last thing I want to do is open a copy of Free42

That's exactly what I mean by ad hoc and help with manual computation. I do the same thing with my little fleet of old hp gems :-)

But I don't feel old........
I mean I do remember lusting after the HP-25 when it first came out and the pure joy of buying one shortly after.
But I don't really feel that old.


I am Japanese and I have a fx-5800p.
Personally, I think that if you can buy TI or HP calculators, you should not buy 5800p.
Because it has no CAS and complex operations is meaningless.
5800p can't calculate even i^i and (-1.6)^(1.5).
Program language is only BASIC style language.
This calculator need many key strokes.
For example, if you calculate the factorial, you must type FUNCTION 1 5.
ABS, Hyperbolic function and its inverse function are the same.

BTW, I don't speak English well. I apologize for my poor English.


I apologize for my poor English.

No apology needed- you made your points very well.

Indeed -- very well spoken, and relevant to the discussion. Thanks!!


Hi all again, finally I have bought the hp 35s. This is my first programmable rpn calc and my impression is good.

Be warned, I am a noob in calculators but this is my first review:

Good complex numbers support, you can covert between polar and rectangular coordinates (if you see them as complex numbers), high quality case and buttons, huge memory for a RPN Keystroke programmable calc, simultaneus equation solver (2*2 an 3*3), it is small and light which it is good for daily use...

On the other hand it has some known lacks, you can do all calculations and connversions between bases but you have to type many buttons. It has not got a function to calculate logarithms in a base other than 10. Also I do not like its logic capabilities: when I do the NOT of 1111b I expect 0000b but I get 1111111111111111110000b (but probably I will not use this feature)...

Perhaps it is very soon to make a judgement but I like this calc.


1) The LN key computes logs to base e.

2) Binary word size is set to 36 bits. Can't change it.


This Message was deleted. This empty message preserves the threading when a post with followup(s) is deleted. If all followups have been removed, the original poster may delete this post again to make this placeholder disappear.


Hi Pablo,

I will forecast your future:

You will keep the 35s and enjoy using it for stuff it is quick and easy for. But then you'll buy a 50G anyway....

best regards,


For easy and normal things I am productive with a programmable calculator. For complex tasks I use computer software like Maple or Matlab.

Edited: 24 Mar 2010, 6:44 p.m.


I think it's normal to get this answer because in binary numbers, you have two kinds, signed and unsigned


On the other hand, the 5800 has a built-in equation library.


If someone is interested I have written a little review with some photos about my new hp 35s.


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