Yoshiki Ohshima writes: > Hi, Steve, >> I am a lurker, but this is an interesting discussion. I am a >> developer in health applications working with current dev release on a >> B4. Calculate is impressive; Pippy is impressive. They each serve a >> purpose which I think fits into an OPLC evolutionist philosophy. > > But, have you actually tried to use Calculate? It could not detect > simple errors properly (which is now fixed), takes 10 seconds to > calculate "3+4", and digits in a long floating point number are > wrapped around, etc.?
Errors ought to be detected as typed, with the text changing color at the point where syntax is violated. So this... 7+5-9*4)-5 ...would be highlighted starting from the ')' character. It may be good to display the expressions twice, once like a normal (C, Java, C#, C++) programming language for editing and once in a proper (TeX, MathML, textbooks) rendering. For the math itself, I suggest feeding expressions into the "bc" program. > Again, this is not a criticism toward Reinier, but rather toward the > fact that keeping up with the rate of change that Sugar and the UI > guideline is not something a volunteer developer can easily cope with. Calculate is in Python, isn't it? Sugar and UI changes are deadly for the non-Python stuff. >> First, there are US toys that are remarkably similar to the OLPC in >> appearance that comprise a simple 4x4 calculator aimed at the under 5 >> year old crowd. Large keys that do arithmetic. I think the idea of clicking on on-screen buttons is fundamentally defective. The keyboard is far easier to use. I suggest displaying an on-screen copy of that, with the valid keystrokes highlighted. One could still use it with the touchpad, if one wanted to suffer. So in the above example, after "7+5-9*4" the ')' key would not be highlighted. Having such an on-screen representation would make it easy to show letter keys remapped as appropriate. For example, a key might serve as sin() normally or as arcsin() when control is used. (BTW, control might be made sticky) > Well, if you consider under 5 years old crowd, then you would oppose > to have variables in Calculate? (BTW, OLPC is not aimed at the crowd, > I believe.) What do you think about the the use of e-notation in it? > How about all these functions available in the tab? Arbitrary named variables are probably not good. Cut-and-paste gives you a variable, and the most recent answer (or two) could implicitly be a variable. If there is a scrolling log of answers, clicking on lines of the log could act as variables. Anything beyond that is probably getting into spreadsheet territory, but there are low-complexity ways to deal with that too: cut-and-paste to a text document, allow drag-and-drop to a saved-data area of the screen, or just scribble on something physical. > Imagine if the functions that are available in the Calculate "mode" > (such as sin, sqrt, etc.) are actually defined in a way that kids can > understand (for example, the Newton-method for sqrt, or even a > graphical version for sin and cos), and if the user goes to the Pippy > "mode", the user can look inside the definition and modify them? That > would be very constructionist. Dear my. I'm all in favor of supporting the bright kids, but that suggestion sounds like grade 12 honors at minimum. _______________________________________________ Devel mailing list [email protected] http://lists.laptop.org/listinfo/devel
