"When" comand
in [HP48]
|
Prev: MacOSX + HP48gx
Next: mmc and mdc
From: Giovanni on 21 Sep 2007 14:48 Hi! I recently used a TI-89 Titanium (I'm, sorry, but I had to...) instead of my 50g and I noticed the presence of a comand named "when". This comand allows the user to plot a system of equation. For example, if one condition is "x>0", then you can tell the calculator to plot "cos(abs(x))" if the first condition is true; you can then tell the calculator to plot "cos(x)" if "x<0". My question is: is there something similar for the 50g, too? I tried to write "WHEN" in the eqw, when I have to insert the function to plot, and such a comand seems to exist because, if you digit "WHEN", you can use brackets after this comand (for example, you're prevented from to doing so if you digit some other letters, for instance "asddfgggf"); thus, the calculator must "understand" the expression "When" as a command; however, this is neither present in the "catalog" menu nor in the User's Guide, so I don't know the syntax (which is certainly different from the one used by TI-89 Titanium). Any advice is welcomed!
From: Graywolf on 21 Sep 2007 15:23 I never use my 50-g for graphing (I don't find it as good as 89s), but an alternative way on the 83 is to type equation and then the condition. Ex: Graph y=x+2 for x>5 so you would type y1=x+2(x>5) So you treat it like a Boolean expression. I'm not sure if the HP can do this, but there must be some way.
From: Andreas Möller on 21 Sep 2007 15:34 Hello, I´m not aware of any command called WHEN. The way you described it just means that the global identifier WHEN is allowed as a variable. The plot-system will also plot programs, so create a program that tests your condition and depending on the test your desired function is drawn. Example: Assumption: you use RPN-Mode and X is the independed variable: « IF X 0.000000 > THEN 'COS(ABS(X))' ELSE 'X^2' END » Store this program in 'EQ' and draw it. You will notice that for the negative x-axis 'COS(ABS(X))' is plotted and for the positiv x-axis 'X^2' is drawn. HTH Andreas http://www.software49g.gmxhome.de
From: dj_jurny on 21 Sep 2007 16:22 Hi all, Another way: eg1: store '(X<0)*COS(ABS(X))+(X>0)*COS(X)' in 'EQ' and draw it, eg2: store '(X<0)*COS(ABS(X))+(X>0)*X^2' in 'EQ' and draw it HTH dj_jurny
From: Virgil on 21 Sep 2007 18:04
In article <1190400492.552077.156370(a)r29g2000hsg.googlegroups.com>, Giovanni <giovanni0ferretti(a)gmail.com> wrote: > Hi! > I recently used a TI-89 Titanium (I'm, sorry, but I had to...) instead > of my 50g and I noticed the presence of a comand named "when". This > comand allows the user to plot a system of equation. For example, if > one condition is "x>0", then you can tell the calculator to plot > "cos(abs(x))" if the first condition is true; you can then tell the > calculator to plot "cos(x)" if "x<0". > My question is: is there something similar for the 50g, too? I tried > to write "WHEN" in the eqw, when I have to insert the function to > plot, and such a comand seems to exist because, if you digit "WHEN", > you can use brackets after this comand (for example, you're prevented > from to doing so if you digit some other letters, for instance > "asddfgggf"); thus, the calculator must "understand" the expression > "When" as a command; however, this is neither present in the "catalog" > menu nor in the User's Guide, so I don't know the syntax (which is > certainly different from the one used by TI-89 Titanium). > Any advice is welcomed! Try 'Y=IFTE(0<X,SIN(X),COS(X))' STEQ ERASE DRAX DRAW The above w ill graph COS(X) for X <= 0 and SIN(X) for X > 0. IFTE is an abbreviation of "if then else". |