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wp34s Adding decimals to fractions
Message #1 Posted by Norman Dziedzic on 2 May 2011, 10:00 a.m.

On the 32sii and 35s I can be in fraction mode and type something like 0.125 + Which will add 1/8 to the number in X.

On the wp34s the same keystrokes don't add anything. Entering an integer works but it seems that as soon as I type the first decimal separator, it wants to see the second one as well.

      
Re: wp34s Adding decimals to fractions
Message #2 Posted by Walter B on 2 May 2011, 11:00 a.m.,
in response to message #1 by Norman Dziedzic

Hi Norman,

Thanks, you found another bug!

Walter

      
Re: wp34s Adding decimals to fractions
Message #3 Posted by Paul Dale on 2 May 2011, 5:43 p.m.,
in response to message #1 by Norman Dziedzic

You are in fraction mode. 0.125 is 0 / 125 which is plain zero.

What would you expect if you added 1.125 ? Or 1.1.125 ?

Where does fraction mode end and real mode being is the question here.

- Pauli

            
Re: wp34s Adding decimals to fractions
Message #4 Posted by gene wright on 2 May 2011, 6:17 p.m.,
in response to message #3 by Paul Dale

Hey Pauli.

I think the assumption is that the 32sII paradigm for fractions is "the way things should work".

                  
Re: wp34s Adding decimals to fractions
Message #5 Posted by Paul Dale on 2 May 2011, 7:15 p.m.,
in response to message #4 by gene wright

Even if it is inconsistent?

I don't have a 32sII to hand so I can't experiment at the moment. However if 1.2 is a half, 0.2 should be 0 IMHO.

The problem might be that we're not changing the display during entry in fraction mode so it isn't clear enough what is happening.

- Pauli

            
Re: wp34s Adding decimals to fractions
Message #6 Posted by Norman Dziedzic on 2 May 2011, 7:21 p.m.,
in response to message #3 by Paul Dale

Quote:
You are in fraction mode. 0.125 is 0 / 125 which is plain zero.

What would you expect if you added 1.125 ? Or 1.1.125 ?

Where does fraction mode end and real mode being is the question here.

- Pauli


Gene is right. I was going by the 32sii standard.

To enter 0/125 on the 32sii you would enter . 0 . 125

The operative part of enter a fraction is that decimal occurs twice in the entry. With only a single . the entry is considered a decimal entry. The 32sii gives the example of entering 5/8 as either . 5 . 8 OR 5 . . 8

Edited: 2 May 2011, 8:15 p.m. after one or more responses were posted

                  
Re: wp34s Adding decimals to fractions
Message #7 Posted by Paul Dale on 2 May 2011, 8:14 p.m.,
in response to message #6 by Norman Dziedzic

I understand the difference now. Shows how often I use fraction mode on the 32sII :-)

- Pauli

                  
Re: wp34s Adding decimals to fractions
Message #8 Posted by Walter B on 2 May 2011, 11:47 p.m.,
in response to message #6 by Norman Dziedzic

Quote:
With only a single . the entry is considered a decimal entry. The 32sii gives the example of entering 5/8 as either . 5 . 8 OR 5 . . 8
That's inconsistent. By plain and simple logic, 5/8 shall be entered as .5.8 - 5..8 enters 5 0/8 !
                        
Re: wp34s Adding decimals to fractions
Message #9 Posted by Norman Dziedzic on 3 May 2011, 12:56 a.m.,
in response to message #8 by Walter B

Quote:

That's inconsistent. By plain and simple logic, 5/8 shall be entered as .5.8 - 5..8 enters 5 0/8 !


For better or worse, it is consistent with the 32sII manual ;-) Perhaps the developers of the 32sII realized that there is virtually no need to ever key in a fraction with numerator of 0.

HOWEVER, this input method which I'm choosing to call a short cut does not work on the 35s. (Yes I know it is technically not a short cut since it is the same number of keystrokes as . 5 . 8 but it is easier to key in because of the repeated .).

Working on a my 32sII with FDISP on.

Keypress   Display
--------   -------
5          5_
.          5._
.          5/_
8          5/8_
<ENTER>    0 5/8

I guess the major question is whether or not the 32SII should be followed exactly or not. If you want to duplicate the 32SII then I highly recommend reading chapter 5 of the 32SII manual which is on the Museum DVDs.

                              
Re: wp34s Adding decimals to fractions
Message #10 Posted by Walter B on 3 May 2011, 4:48 a.m.,
in response to message #9 by Norman Dziedzic

We don't follow the 32SII exactly - you will never see anything like 0 5/8 on the wp34s I hope ;-)

When PROFRC is set, the logic behind our input is:

.5.8 ENTER results in 5/8
.58 ENTER shall result in 29/50
5.8 ENTER shall result in 5 4/5
5.8.9 ENTER results in 5 8/9
5.9.8 ENTER results in 6 1/8
5..8 ENTER results in 5 0/1 
with the 0/1 indicating you're in fraction mode. One may discuss whether the 0/1 is necessary or should be discarded, since the missing decimal mark may be sufficient evidence.

Walter

                                    
Re: wp34s Adding decimals to fractions
Message #11 Posted by Marcus von Cube, Germany on 3 May 2011, 10:43 a.m.,
in response to message #10 by Walter B

The decimal mark is missing in most cases, so we need some indication.

                                    
Re: wp34s Adding decimals to fractions (now in)
Message #12 Posted by Walter B on 6 May 2011, 2:25 a.m.,
in response to message #10 by Walter B

Hi Norman, all,

FYI, the latest build (820) handles all such inputs and operations properly, as far as I checked. Enjoy - and continue testing :-) !

Walter


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