Number in HP Prime

[ggauny@live.fr]

Hi,

I have a problem. I was waiting -5/7 for x and -22/7 for y but I obtained decimal of the divisions and not the fractions in solver app or linsolver app. I have choosed "EXACT" in CAS, but no fractions only decimal number.

Certainely I miss configuration, but how to have result in form of fractions ?

Thanks.

[Joe Horn]

(09-02-2016 10:09 AM)ggauny@live.fr Wrote:  Hi,

I have a problem. I was waiting -5/7 for x and -22/7 for y but I obtained decimal of the divisions and not the fractions in solver app or linsolver app. I have choosed "EXACT" in CAS, but no fractions only decimal number.

Certainely I miss configuration, but how to have result in form of fractions ?

The Solver and Linear Solver apps are numeric solvers, not symbolic solvers. In other words, they are like Home operations, not CAS operations. Whenever you want exact (symbolic, algebraic) results, use the CAS.

[Aries]

(09-02-2016 10:09 AM)ggauny@live.fr Wrote:  Hi,

I have a problem. I was waiting -5/7 for x and -22/7 for y but I obtained decimal of the divisions and not the fractions in solver app or linsolver app. I have choosed "EXACT" in CAS, but no fractions only decimal number.

Certainely I miss configuration, but how to have result in form of fractions ?

Thanks.

You can't, in order to get the "exact" solution you have to use SOLVE in CAS mode, not SOLVER/LINEAR SOLVER apps ;-)
Best,

Aries :-)

[ggauny@live.fr]

Hi,

Thank for you all.

[Nigel (UK)]

If you use the Solver to solve for X and obtain (for example) 10.71428571429 you can return to the Home screen, display the value of X and then press the "a b/c" key. That converts the decimal into a fraction for display.

Sorry if you already know this!

Nigel (UK)

[Spybot]

I'm not sure in previous versions of firmware... but on FW:10637 it does convert to fractions by pressing the "a b/c" key, while still in the Linear solver App.

[ggauny@live.fr]

Again thank for the trick "a/b fraction. I was not knowing this.

Goods regards.

[Joe Horn]

(09-19-2016 06:58 AM)ggauny@live.fr Wrote:  Again thank for the trick "a/b fraction. I was not knowing this.

Be careful when using the fraction button in Home. It doesn't always return a fraction exactly equal to the input. Its purpose is to display a fraction that is close to the input, and you can control its precision by changing the display mode. For example, in Home, in Fixed 2 mode, pi [a b/c] returns 22/7, but in Fixed 5 mode it returns 355/113. Standard display mode is similar to Fixed 11. Here's a trick that nobody has mentioned yet: Set Fixed display mode, then go into CAS and type HDigits:=12. That will set your machine to Fixed 12 mode(!), which returns fractions with even higher precision than Fixed 11.

When the fraction button is used in CAS, it uses the "exact()" function, whose precision is controlled not by the display mode, but by the value of the CAS setting called "epsilon" (see page 2 of the CAS Settings).

[ggauny@live.fr]

Hi Joe,
Very interesting reply ! How can you know all this things (and in 50g too) ? I have puted in application your advertising.

Thank.