New Acron RPN Calculator for Android

[vanLudwig]

Based on Nigel's comments, I'm testing out swapping the decimal button for an EE button as soon as you type a decimal. I think that would flow naturally in most situations. Worst case, you would have to type an unneeded decimal before you could type an EE.

[vanLudwig]

I made a new update available through the Play Store late last night.

- I added memory store, recall and clear buttons to the stack menu. You can select any line on the stack and store it.

- The Decimal button now toggles between Decimal and EE based on whether the console text contains a decimal. I removed EE button on the PI menu.

[Nigel (UK)]

The EE/decimal works really well; thank you! I find that I am starting to miss the calculation history feature on other RPN machines; I also like not having to think about angle mode.

Suggestion: how about adding a LastX function? It could replace MC on the Stack menu.

One minor point: quite often, (integer)^(positive integer) gives an answer ending in a decimal point, e.g., "2^16=65536." Would it be possible to arrange that, where possible, these numbers are automatically integers?

Nigel (UK)

[vanLudwig]

(07-04-2016 04:12 PM)Nigel (UK) Wrote:  I find that I am starting to miss the calculation history feature on other RPN machines

You've discovered my plot to take over the RPN market

(07-04-2016 04:12 PM)Nigel (UK) Wrote:  Suggestion: how about adding a LastX function? It could replace MC on the Stack menu.

Good idea. I wasn't aware of LastX prior to your post, but after doing some research, this looks like a valuable addition. The main reason I had a MC button was to make the button layout work, so I don't mind replacing it.

(07-04-2016 04:12 PM)Nigel (UK) Wrote:  One minor point: quite often, (integer)^(positive integer) gives an answer ending in a decimal point, e.g., "2^16=65536." Would it be possible to arrange that, where possible, these numbers are automatically integers?

It happens for exponents over 9. My "perfect" number engine computes exponents by repeated multiplication. For exponents over 9, it converts the "perfect" number to floating point and uses logarithms. I will modify this to check the inputs and look for oportunities to round the result back to a perfect number. Perfect numbers use 32 bit integers, so 10^10 already overflows, so this will only help for very small base values.

[vanLudwig]

New features mentioned above are available in build 1.0.4 released today.

[ijabbott]

I downloaded the free version and was impressed by the novel stack display and clean interface, so I splashed out £0.79 on the paid version.

I have a few suggestions for additional that should be simple to implement:

• csc⁻¹(x), sec⁻¹(x), and cot⁻¹(x)
• degree forms of csc(x), sec(x), and cot(x), and their inverse functions, if implemented (but this would push the sin, cos and tan button menus to three pages each)
• there is space on the ? button soft menu for another constant, possibly the golden ratio, ?
• the gamma function ?(x), or failing that, implement x! for real numbers as ?(x+1)
  

In addition, rectangular to polar and polar to rectangular conversions would be nice (in both radian and degree forms), but as those functions would replace two values on the stack with two new functions, it would wreck your nice, augmented stack display something horrid! An alternative would be to implement them as part of complex number support, but you might not want to go down that road just yet!

Thanks for producing a nice calculator app!

[vanLudwig]

Thanks, I'm glad you like it.

Imaginary number support has been on my radar for awhile now. My plan was for i to fill the blank spot on the PI menu, and for there to be a new page in the math menu for complex functions. My math skills are sufficient to implement complex arithmetic in both rectangular and polar (including integer powers), but insufficient to implement complex trig.

I've never met anyone passionate about csc, sec, and cot before. I mainly just put them there to fill an empty button. Is there one function that you would most like to see to fill the last empty button? If not, the layout would fit okay with three rows of buttons: secd, asecd, sec, asec | cosh, acosh, sech, asech.

I would have to do some more investigation on gamma function algorithms to determine if this is viable. Do you need the complex version?

[ijabbott]

(08-13-2016 06:41 PM)vanLudwig Wrote:  Imaginary number support has been on my radar for awhile now. My plan was for i to fill the blank spot on the PI menu, and for there to be a new page in the math menu for complex functions. My math skills are sufficient to implement complex arithmetic in both rectangular and polar (including integer powers), but insufficient to implement complex trig.

The golden ratio was just suggested as a space filler, but yes, i would make more sense if complex numbers are implemented.

Perhaps there are library functions you can access for complex trig etc.

Quote:I've never met anyone passionate about csc, sec, and cot before. I mainly just put them there to fill an empty button. Is there one function that you would most like to see to fill the last empty button? If not, the layout would fit okay with three rows of buttons: secd, asecd, sec, asec | cosh, acosh, sech, asech.

I can't say I've used sec, csc and cot much, but I suggested the extra functions for symmetry with the other trig functions. If choosing between one of asec and secd, I think asec would be more useful, as it's always handy to have the inverse of a function.

Quote:I would have to do some more investigation on gamma function algorithms to determine if this is viable. Do you need the complex version?

Calculating the gamma function for real numbers looks quite complicated, though you may find a library function to do it. Calculating the gamma function of a complex number looks a lot more complicated!

[vanLudwig]

Released a huge new update today. Added support for complex numbers, including complex trig, powers, logs, and hyperbolics. Also implemented perfect form of logs and e^x (this was very important for keeping complex calculations perfect). As a result of implementing perfect logs, I also got a lot of perfect hyperbolic trig for free.



As requested, I implemented acsc, asec, and acot. All advanced trig functions (including polar complex number functions) are now dual-use toolbar buttons - tap for radians version, long-press for degrees version. Basic trig functions continue to have separate buttons for radians and degrees.

Also, a port to iPhone is currently underway. Be on the lookout for that to be released in the next couple months.