Calculus
Sat, 08/08/2009 - 07:38
Enjoy the GUI design. Very interesting idea. I can see this becoming my interface of choice. However, I can't figure out how to do integration and differentiation in Pi Cubed Lite. Is this possible in the full version? I've only had the program for a day and have not used it much, but I need those capabilities. Thank you.
Sat, 08/08/2009 - 22:31
#2
Ahh, I understand better now what Pi^3 can do. Perhaps you can grab some stuff from Sage (Python based) to help do symbolic math down the line. keep it up!
Mon, 08/10/2009 - 18:17
#3
Lovely interface. This could be the best ever calculator for the iPhone.
Questions: is there an undo function? can the result be displayed in a fixed decimal format? can thousands separation be implemented? have you considered using an alternative 3x3 number entry that pops up?
Mon, 08/10/2009 - 19:43
#4
Questions: is there an undo function?
Not yet, but it's what I'm working on right now for the next release.
can the result be displayed in a fixed decimal format? can thousands separation be implemented?
I'm going to be adding formatting options for all numbers, such as scientific notation, but I still need to work through some interface designs.
have you considered using an alternative 3x3 number entry that pops up?
I experimented with a ring-like menu that popped up around the number you were currently editing, but it got in the way too much to be useful. If I can find a way to make it work well, I may try it again.
Thu, 08/27/2009 - 17:55
#5
I like the interface! I think if you made this a symbolic math process with solving functions you could charge the same premiums as mathcad etc. I understand that is a long way off. The following is a wish list of items which are not quite as difficult, but would be greatly appreciated if you were to consider for future releases/updates.
1. I wish there was the ability to past copied selection back into new fields within the application. Its really nice having the ability to put so much descriptive information about each variable. (ie. Area in^2). But it sucks that you can not copy the variable and past it in a new equation you are writing.
2. I wish there was some way to upload equations and download equations from a central data base. Check out a web site for excel called "excel calc". The way they do there equation repository is perfect, and easy to use. This would allow the ability to expand on custom libraries.
3. I wish there was some way to move the equations in your custom library around. Ie make all the equations titled circle show up together. Currently they display in the order they were imputed. Even having them sort alphabetically would be an improvement.
4. Some sort of variable solver is definitely needed. It would be wonderful to be able to take an expression and have it algebraically rewrite itself so that you are solving for a different variable. While that is difficult to code, and a long way off; having a solver is not.
Example
If I had Q=Cv*sqrt(deltaP) as an equation and was interested in solving for the Cv, currently I would have to retype the entire equation leaving the Cv on the write hand side. It would be better if the solver just looked for when every variable but one is defined, and then used an iteration approach to guess the missing variables value. This is how calculators like HP use there solve functions.
5. I downloaded the "graphy" grapher as well. It would be nice if there was a dialog box that gave the option of mapping variables to variables that graphy uses. For example in the if I wanted to do a surface graph the equation above, I would set Q=x, and deltP=y, and look at the result Cv on the z axis. (Currently this is done in the graphy editor, but why not have the change take place prior to exporting it to graphy.)
Mon, 08/31/2009 - 09:57
#6
Sorry for the slow response.
1. I wish there was the ability to past copied selection back into new fields within the application. Its really nice having the ability to put so much descriptive information about each variable. (ie. Area in^2). But it sucks that you can not copy the variable and past it in a new equation you are writing.
That's a good point. I'm working on extending the copy-and-paste support to let you paste into the equation, so I'll see about extending that to copying and pasting entire variables.
2. I wish there was some way to upload equations and download equations from a central data base. Check out a web site for excel called "excel calc". The way they do there equation repository is perfect, and easy to use. This would allow the ability to expand on custom libraries.
This is an interesting idea that others have suggested, as well, but I'd have to think about how best to pull this off. Something like this could work well, like how Graffletopia and OmniGraflle interact, but it would require me to curate the submitted equations to make sure that someone doesn't abuse the system.
3. I wish there was some way to move the equations in your custom library around. Ie make all the equations titled circle show up together. Currently they display in the order they were imputed. Even having them sort alphabetically would be an improvement.
There might be a slight glitch in the way that equations are sorted, causing the out-of-order behavior you describe. This should be fixed in the next version. I'll also take a look at arbitrary sorting of the equations.
4. Some sort of variable solver is definitely needed. It would be wonderful to be able to take an expression and have it algebraically rewrite itself so that you are solving for a different variable. While that is difficult to code, and a long way off; having a solver is not.
A true symbolic solver is incredibly difficult to implement, an iterative numerical solver is merely difficult. It's definitely something I'd like to add, but making it work and having it be performant on the iPhone is a challenge.
5. I downloaded the "graphy" grapher as well. It would be nice if there was a dialog box that gave the option of mapping variables to variables that graphy uses. For example in the if I wanted to do a surface graph the equation above, I would set Q=x, and deltP=y, and look at the result Cv on the z axis. (Currently this is done in the graphy editor, but why not have the change take place prior to exporting it to graphy.)
I'll see if there's a reasonable way to implement this. There's also the possibility that Grafly could be extended with the capability to plot more than just X, Y, and Z.
Sun, 01/31/2010 - 22:00
#7
Hello!
great app!
would it be easier to allow the answers to show in scientific notation and implement constructing equations later? That would be really helpful if there weren't 23 0's to count :)
Thanks!
Unfortunately, true symbolic math is not handled by the application yet. I designed this primarily as a numerical calculation application, so my focus has been on features towards that end. The new capabilities I'm working on now are all extensions of the base calculation capabilities of the application.
I do plan on eventually trying to tackle symbolic math, but it's an extremely difficult task (thus the higher prices on tools like Maple and Mathematica). That's definitely a task for a version 2.0, but I don't imagine we'll see that for a while. Sorry if that steers you away from the application.