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The Jolla calculator seems too simple when first trying it and yet it has features that simplify calculations without adding clutter. But it uses in-fix notation and it has no scientific functionality.

So I downloaded Quanto Fa from the Jolla Store. Quanto Fa uses reverse polish notation (RPN) which is the way I usually think. It's nice and gets the job done, but the Jolla calculator gave some inspiration. So I decided to wish for a slightly unlike RPN calculator app.

See, most RPN calculators have buttons for certain stack modifiers. Swapping the latest two stack objects and rotating the last four are common. There are also some memory registers with related buttons (STO and RCL). The Jolla calculator handles things in another way. After making a calculation it is possible to copy that number as part of a new calculation. It's a handy system that erases the need for dedicated buttons for storing and retrieving numbers from memory. So while trying to copy the nice layout of the Jolla calculator, but adjusting it for the special needs of a RPN calculator, a strange idea was born.

Could all stack manipulation be done with the touch screen?

If the number of function buttons could be minimized then more of the screen could hold a stack of registers. With my HP calculator there are only four of these registers, but why have such a limit on a touch-screen app?

The trigonometric functions would have the arc versions available with a long press and similar arrangements can be done with other function pairs such as square root and x squared. Combining functions brought the number of buttons down. I think the end result was something like ten buttons for a really minimalistic calculator like Quanto Fa, but the number of functions could be increased. I just don't know what to add...

The look would be something like the Jolla calculator app. There would be groups of buttons marked with different colours. In fact, the lower part would be almost identical to the Jolla counterpart. The only exception would be [Enter] that would replace [ = ]. Above the keypad there would be two (or maybe three) rows of function buttons. The rest of the screen would show a scrollable stack of numbers. The latest number would be in a bigger font than the others. My guess is that six or even eight stack items would be visible at once on the screen. These registers can be manipulated by simply touching or dragging. And the entire stack can be emptied in the same manner as in the Jolla calculator.

That is the calculator app I would like to find in the Jolla Store some day.

There’s no need for programming or graphs. A minimalistic calculator will do.

The Jolla calculator seems too simple when first trying it and yet it has features that simplify calculations without adding clutter. But it uses in-fix notation and it has no scientific functionality.

So I downloaded Quanto Fa from the Jolla Store. Quanto Fa uses reverse polish notation (RPN) which is the way I usually think. It's nice and gets the job done, but the Jolla calculator gave some inspiration. So I decided to wish for a slightly unlike RPN calculator app.

See, most RPN calculators have buttons for certain stack modifiers. Swapping the latest two stack objects and rotating the last four are common. There are also some memory registers with related buttons (STO and RCL). The Jolla calculator handles things in another way. After making a calculation it is possible to copy that number as part of a new calculation. It's a handy system that erases the need for dedicated buttons for storing and retrieving numbers from memory. So while trying to copy the nice layout of the Jolla calculator, but adjusting it for the special needs of a RPN calculator, a strange idea was born.

Could all stack manipulation be done with the touch screen?

If the number of function buttons could be minimized then more of the screen could hold a stack of registers. With my HP calculator there are only four of these registers, but why have such a limit on a touch-screen app?

The trigonometric functions would have the arc versions available with a long press and similar arrangements can be done with other function pairs such as square root and x squared. Combining functions brought the number of buttons down. I think the end result was something like ten buttons for a really minimalistic calculator like Quanto Fa, but the number of functions could be increased. I just don't know what to add...

The look would be something like the Jolla calculator app. There would be groups of buttons marked with different colours. In fact, the lower part would be almost identical to the Jolla counterpart. The only exception would be [Enter] that would replace [ = ]. Above the keypad there would be two (or maybe three) rows of function buttons. The rest of the screen would show a scrollable stack of numbers. The latest number would be in a bigger font than the others. My guess is that six or even eight stack items would be visible at once on the screen. These registers can be manipulated by simply touching or dragging. And the entire stack can be emptied in the same manner as in the Jolla calculator.

That is the calculator app I would like to find in the Jolla Store some day.

There’s no need for programming or graphs. A minimalistic calculator will do.

The Jolla calculator seems too simple when first trying it and yet it has features that simplify calculations without adding clutter. But it uses in-fix notation and it has no scientific functionality.

So I downloaded Quanto Fa from the Jolla Store. Quanto Fa uses reverse polish notation (RPN) which is the way I usually think. It's nice and gets the job done, but the Jolla calculator gave some inspiration. So I decided to wish for a slightly unlike RPN calculator app.

See, most RPN calculators have buttons for certain stack modifiers. Swapping the latest two stack objects and rotating the last four are common. There are also some memory registers with related buttons (STO and RCL). The Jolla calculator handles things in another way. After making a calculation it is possible to copy that number as part of a new calculation. It's a handy system that erases the need for dedicated buttons for storing and retrieving numbers from memory. So while trying to copy the nice layout of the Jolla calculator, but adjusting it for the special needs of a RPN calculator, a strange idea was born.

Could all stack manipulation be done with the touch screen?

If the number of function buttons could be minimized then more of the screen could hold a stack of registers. With my HP calculator there are only four of these registers, but why have such a limit on a touch-screen app?

The trigonometric functions would have the arc versions available with a long press and similar arrangements can be done with other function pairs such as square root and x squared. Combining functions brought the number of buttons down. I think the end result was something like ten buttons for a really minimalistic calculator like Quanto Fa, but the number of functions could be increased. I just don't know what to add...

The look would be something like the Jolla calculator app. There would be groups of buttons marked with different colours. In fact, the lower part would be almost identical to the Jolla counterpart. The only exception would be [Enter] that would replace [ = ]. Above the keypad there would be two (or maybe three) rows of function buttons. The rest of the screen would show a scrollable stack of numbers. The latest number would be in a bigger font than the others. My guess is that six or even eight stack items would be visible at once on the screen. These registers can be manipulated by simply touching or dragging. And the entire stack can be emptied in the same manner as in the Jolla calculator.

That is the calculator app I would like to find in the Jolla Store some day.

There’s no need for programming or graphs. A minimalistic calculator will do.

The Jolla calculator seems too simple when first trying it and yet it has features that simplify calculations without adding clutter. But it uses in-fix notation and it has no scientific functionality.

So I downloaded Quanto Fa from the Jolla Store. Quanto Fa uses reverse polish notation (RPN) which is the way I usually think. It's nice and gets the job done, but the Jolla calculator gave some inspiration. So I decided to wish for a slightly unlike RPN calculator app.

See, most RPN calculators have buttons for certain stack modifiers. Swapping the latest two stack objects and rotating the last four are common. There are also some memory registers with related buttons (STO and RCL). The Jolla calculator handles things in another way. After making a calculation it is possible to copy that number as part of a new calculation. It's a handy system that erases the need for dedicated buttons for storing and retrieving numbers from memory. So while trying to copy the nice layout of the Jolla calculator, but adjusting it for the special needs of a RPN calculator, a strange idea was born.

Could all stack manipulation be done with the touch screen?

If the number of function buttons could be minimized then more of the screen could hold a stack of registers. With my HP calculator there are only four of these registers, but why have such a limit on a touch-screen app?

The trigonometric functions would have the arc versions available with a long press and similar arrangements can be done with other function pairs such as square root and x squared. Combining functions brought the number of buttons down. I think the end result was something like ten buttons for a really minimalistic calculator like Quanto Fa, but the number of functions could be increased. I just don't know what to add...

The look would be something like the Jolla calculator app. There would be groups of buttons marked with different colours. In fact, the lower part would be almost identical to the Jolla counterpart. The only exception would be [Enter] that would replace [ = ]. Above the keypad there would be two (or maybe three) rows of function buttons. The rest of the screen would show a scrollable stack of numbers. The latest number would be in a bigger font than the others. My guess is that six or even eight stack items would be visible at once on the screen. These registers can be manipulated by simply touching or dragging. And the entire stack can be emptied in the same manner as in the Jolla calculator.

That is the calculator app I would like to find in the Jolla Store some day.

There’s no need for programming or graphs. A minimalistic calculator will do.

Update

There seems to be almost enough code for the unlike RPN calculator. Both Quanto Fa and RPNcalc are useful in their current states (I use them both). Both have fragments worth using as part of a new mix.

The touch stack is still missing, though. The deep stack of RPNcalc gets hard to handle because the deepest registers are beyond the reach of the stack manipulators. The user needs to drop registers to reach the older values. If stack registers could be manipulated by dragging then all registers would be useful.

People using RPN calculators are used to having very few registers. Usually just four. They are also used to the fact that beyond those registers the numbers are lost. The unlike RPN calculator could also let the oldest values fall off the stack. Users expect that. So the number of registers could be limited. Naming the first ones X, Y, Z would make the button labels familiar for old hands and easy to understand for newbies. The rest of the registers could simply be numbered 0 to 9, if they need to be numbered at all.

The Jolla calculator still has the sleekest layout of all calculators I've ever seen. I would very much like to have a similar design for the RPN variant. Maybe I should doodle a simple mock-up?

The Jolla calculator seems too simple when first trying it and yet it has features that simplify calculations without adding clutter. But it uses in-fix notation and it has no scientific functionality.

So I downloaded Quanto Fa from the Jolla Store. Quanto Fa uses reverse polish notation (RPN) which is the way I usually think. It's nice and gets the job done, but the Jolla calculator gave some inspiration. So I decided to wish for a slightly unlike RPN calculator app.

See, most RPN calculators have buttons for certain stack modifiers. Swapping the latest two stack objects and rotating the last four are common. There are also some memory registers with related buttons (STO and RCL). The Jolla calculator handles things in another way. After making a calculation it is possible to copy that number as part of a new calculation. It's a handy system that erases the need for dedicated buttons for storing and retrieving numbers from memory. So while trying to copy the nice layout of the Jolla calculator, but adjusting it for the special needs of a RPN calculator, a strange idea was born.

Could all stack manipulation be done with the touch screen?

If the number of function buttons could be minimized then more of the screen could hold a stack of registers. With my HP calculator there are only four of these registers, but why have such a limit on a touch-screen app?

The trigonometric functions would have the arc versions available with a long press and similar arrangements can be done with other function pairs such as square root and x squared. Combining functions brought the number of buttons down. I think the end result was something like ten buttons for a really minimalistic calculator like Quanto Fa, but the number of functions could be increased. I just don't know what to add...

The look would be something like the Jolla calculator app. There would be groups of buttons marked with different colours. In fact, the lower part would be almost identical to the Jolla counterpart. The only exception would be [Enter] that would replace [ = ]. Above the keypad there would be two (or maybe three) rows of function buttons. The rest of the screen would show a scrollable stack of numbers. The latest number would be in a bigger font than the others. My guess is that six or even eight stack items would be visible at once on the screen. These registers can be manipulated by simply touching or dragging. And the entire stack can be emptied in the same manner as in the Jolla calculator.

That is the calculator app I would like to find in the Jolla Store some day.

There’s no need for programming or graphs. A minimalistic calculator will do.

Update

There seems to be almost enough code for the unlike RPN calculator. Both Quanto Fa and RPNcalc are useful in their current states (I use them both). Both have fragments worth using as part of a new mix.

The touch stack is still missing, though. The deep stack of RPNcalc gets hard to handle because the deepest registers are beyond the reach of the stack manipulators. The user needs to drop registers to reach the older values. If stack registers could be manipulated by dragging then all registers would be useful.

People using RPN calculators are used to having very few registers. Usually just four. They are also used to the fact that beyond those registers the numbers are lost. The unlike RPN calculator could also let the oldest values fall off the stack. Users expect that. So the number of registers could be limited. Naming the first ones X, Y, Z would make the button labels familiar for old hands and easy to understand for newbies. The rest of the registers could simply be numbered 0 to 9, if they need to be numbered at all.

The Jolla calculator still has the sleekest layout of all calculators I've ever seen. I would very much like to have a similar design for the RPN variant. Maybe I should doodle a simple mock-up?

The "flu" update

A flu gave me unexpected time to think. ...and a slightly fuzzy brain too...

The stack items could have three sizes
Different font sizes would be of good use to enhance readability and to save screen estate.

1. The Entry register
   The X register, where the current numbers go should have the largest font.

2. The Marked registers
   Y, Z and T are important for a number of functions and should have a medium size font.

3. The Unmarked registers
   These registers hold values in an unusually deep stack (probably a dozen) and should have reduced font size to save screen estate. size.

Functions grouped like accents
When typing there is the possibility to choose accents by longpressing the base character. A similar use is with the virtual keyboard layouts too. Screen estate can be saved for the stack by having groups of functions. Instead of having three buttons for SIN/arcSIN, COS/arcCOS and TAN/arcTAN, it would be possible to put all those six functions (and more) side by side with a single TRIG button. Each button could group related functions. With some luck and careful thinking there might be a chance to shrink the basic function buttons to a single row on top of the keyboard. There is room for a lot of functions that way.

Number bases (Optional)
The numeric keypad could have different number bases in a similar fashion. Longpress the zero button and choose from BIN, OCT and HEX (if you already use DEC). The pad remains the same size so the hex variant has landscape low keys. 0.E 123 456 789 ABC DEF might be a possible layout. This way of handling the keypad would be consistent with the rest of the system, imho.

The Jolla calculator seems too simple when first trying it and yet it has features that simplify calculations without adding clutter. But it uses in-fix notation and it has no scientific functionality.

So I downloaded Quanto Fa from the Jolla Store. Quanto Fa uses reverse polish notation (RPN) which is the way I usually think. It's nice and gets the job done, but the Jolla calculator gave some inspiration. So I decided to wish for a slightly unlike RPN calculator app.

See, most RPN calculators have buttons for certain stack modifiers. Swapping the latest two stack objects and rotating the last four are common. There are also some memory registers with related buttons (STO and RCL). The Jolla calculator handles things in another way. After making a calculation it is possible to copy that number as part of a new calculation. It's a handy system that erases the need for dedicated buttons for storing and retrieving numbers from memory. So while trying to copy the nice layout of the Jolla calculator, but adjusting it for the special needs of a RPN calculator, a strange idea was born.

Could all stack manipulation be done with the touch screen?

If the number of function buttons could be minimized then more of the screen could hold a stack of registers. With my HP calculator there are only four of these registers, but why have such a limit on a touch-screen app?

The trigonometric functions would have the arc versions available with a long press and similar arrangements can be done with other function pairs such as square root and x squared. Combining functions brought the number of buttons down. I think the end result was something like ten buttons for a really minimalistic calculator like Quanto Fa, but the number of functions could be increased. I just don't know what to add...

The look would be something like the Jolla calculator app. There would be groups of buttons marked with different colours. In fact, the lower part would be almost identical to the Jolla counterpart. The only exception would be [Enter] that would replace [ = ]. Above the keypad there would be two (or maybe three) rows of function buttons. The rest of the screen would show a scrollable stack of numbers. The latest number would be in a bigger font than the others. My guess is that six or even eight stack items would be visible at once on the screen. These registers can be manipulated by simply touching or dragging. And the entire stack can be emptied in the same manner as in the Jolla calculator.

That is the calculator app I would like to find in the Jolla Store some day.

There’s no need for programming or graphs. A minimalistic calculator will do.

There seems to be almost enough code for the unlike RPN calculator. Both Quanto Fa and RPNcalc are useful in their current states (I use them both). Both have fragments worth using as part of a new mix.

The touch stack is still missing, though. The deep stack of RPNcalc gets hard to handle because the deepest registers are beyond the reach of the stack manipulators. The user needs to drop registers to reach the older values. If stack registers could be manipulated by dragging then all registers would be useful.

People using RPN calculators are used to having very few registers. Usually just four. They are also used to the fact that beyond those registers the numbers are lost. The unlike RPN calculator could also let the oldest values fall off the stack. Users expect that. So the number of registers could be limited. Naming the first ones X, Y, Z would make the button labels familiar for old hands and easy to understand for newbies. The rest of the registers could simply be numbered 0 to 9, if they need to be numbered at all.

The Jolla calculator still has the sleekest layout of all calculators I've ever seen. I would very much like to have a similar design for the RPN variant. Maybe I should doodle a simple mock-up?

A flu gave me unexpected time to think. ...and a slightly fuzzy brain too...

The stack items could have three sizes
Different font sizes would be of good use to enhance readability and to save screen estate.

1. The Entry register
   The X register, where the current numbers go should have the largest font.

2. The Marked registers
   Y, Z and T are important for a number of functions and should have a medium size font.

3. The Unmarked registers
   These registers hold values in an unusually deep stack (probably a dozen) and should have reduced size.

Functions grouped like accents
When typing there is the possibility to choose accents by longpressing the base character. A similar use is with the virtual keyboard layouts too. Screen estate can be saved for the stack by having groups of functions. Instead of having three buttons for SIN/arcSIN, COS/arcCOS and TAN/arcTAN, it would be possible to put all those six functions (and more) side by side with a single TRIG button. Each button could group related functions. With some luck and careful thinking there might be a chance to shrink the basic function buttons to a single row on top of the keyboard. There is room for a lot of functions that way.

Number bases (Optional)
The numeric keypad could have different number bases in a similar fashion. Longpress the zero button and choose from BIN, OCT and HEX (if you already use DEC). The pad remains the same size so the hex variant has landscape low keys. 0.E 123 456 789 ABC DEF might be a possible layout. This way of handling the keypad would be consistent with the rest of the system, imho.