Jeff Liebermann <jeffl@cruzio.com> wrote:
> On Tue, 18 Jan 2022 06:27:35 +0700, John B. <slocombjb@gmail.com>
> wrote:
>
>> Yes, I tried one, belonging to a co-worker and I guess my brain
>> doesn't work the way that HP does. Enter 1,3, divide doesn't seem
>> logical, to me anyway (:-)
>
> Try instead: 1 Enter 3 Divide
>
> RPM works nicely for me because all I need to remember is to enter the
> number first and then what I want to do with it (add subtract multiply
> divide). Algebraic wants me to decide what I want to do with the
> number before I enter it. That's not the way I think which is why I
> prefer RPM notation. However, on single line display RPM calculators,
> I still have problems remembering what I pushed into the stack
> (sequentially accessed memory). I also learned algebraic before I
> learned RPM, making unlearning algebraic.
>

Not to sound to ignorant but don’t you mean RPN as in reverse Polish
notation?

<snip>

On 1/19/2022 6:45 AM, Duane wrote:
> Jeff Liebermann <jeffl@cruzio.com> wrote:
>> On Tue, 18 Jan 2022 06:27:35 +0700, John B. <slocombjb@gmail.com>
>> wrote:
>>
>>> Yes, I tried one, belonging to a co-worker and I guess my brain
>>> doesn't work the way that HP does. Enter 1,3, divide doesn't seem
>>> logical, to me anyway (:-)
>>
>> Try instead: 1 Enter 3 Divide
>>
>> RPM works nicely for me because all I need to remember is to enter the
>> number first and then what I want to do with it (add subtract multiply
>> divide). Algebraic wants me to decide what I want to do with the
>> number before I enter it. That's not the way I think which is why I
>> prefer RPM notation. However, on single line display RPM calculators,
>> I still have problems remembering what I pushed into the stack
>> (sequentially accessed memory). I also learned algebraic before I
>> learned RPM, making unlearning algebraic.
>>
>
>
> Not to sound to ignorant but don’t you mean RPN as in reverse Polish
> notation?
>
> <snip>
>

Mr Krygowski finds it intuitive.

--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971

On Wednesday, January 19, 2022 at 8:55:47 AM UTC-5, AMuzi wrote:
> On 1/19/2022 6:45 AM, Duane wrote:
> > Jeff Liebermann <je...@cruzio.com> wrote:
> >> On Tue, 18 Jan 2022 06:27:35 +0700, John B. <sloc...@gmail.com>
> >> wrote:
> >>
> >>> Yes, I tried one, belonging to a co-worker and I guess my brain
> >>> doesn't work the way that HP does. Enter 1,3, divide doesn't seem
> >>> logical, to me anyway (:-)
> >>
> >> Try instead: 1 Enter 3 Divide
> >>
> >> RPM works nicely for me because all I need to remember is to enter the
> >> number first and then what I want to do with it (add subtract multiply
> >> divide). Algebraic wants me to decide what I want to do with the
> >> number before I enter it. That's not the way I think which is why I
> >> prefer RPM notation. However, on single line display RPM calculators,
> >> I still have problems remembering what I pushed into the stack
> >> (sequentially accessed memory). I also learned algebraic before I
> >> learned RPM, making unlearning algebraic.
> >>
> >
> >
> > Not to sound to ignorant but don’t you mean RPN as in reverse Polish
> > notation?
> >
> > <snip>
> >
>
> Mr Krygowski finds it intuitive.
> --

Many people do, though not me. I can do it, I just don't like it. Too many years of PEMDAS.

On Sunday, January 16, 2022 at 8:16:15 PM UTC-8, Joy Beeson wrote:
> On Sat, 15 Jan 2022 06:37:58 -0800 (PST), William Crowell
> <retrog...@gmail.com> wrote:
>
> > But using friction shifters on the downtube builds character.
> How can something so easy build character?
>
> --
> Joy Beeson
> joy beeson at centurylink dot net
> http://wlweather.net/PAGEJOY/

How can something so easy build character?
It depends on how much character you had in the first place; i.e., what is the starting point?

On 1/19/2022 8:55 AM, AMuzi wrote:
> On 1/19/2022 6:45 AM, Duane wrote:
>> RPN as in reverse Polish
>> notation?
>>
>> <snip>
>>
>
> Mr Krygowski finds it intuitive.

Absolutely. You put in one number. "Enter" serves to tell the computer
that there are no more digits in that number.

Then you put in the second, and tell the calculator what to do with them.

For long, complex calculations (the kind requiring multiple levels of
parentheses with algebraic calculators) you proceed just as you would if
doing them by hand - i.e. you work from the inside out.

For those, you sometimes have to begin another phase by "Enter"ing
another number. That bumps your previous result up on the stack. In
practice, the previous result you need is almost always just above the
current spot on the stack. The process flows very smoothly.

I've taught hundreds of students how to efficiently use calculators. For
simple calculations, there's not much difference. But for calculations
like this: https://en.wikipedia.org/wiki/Von_Mises_yield_criterion
RPN is far more efficient, far less error-prone.

--
- Frank Krygowski

On Wed, 19 Jan 2022 12:45:57 -0000 (UTC), Duane
<no_email@invalid.invalid> wrote:

>Jeff Liebermann <jeffl@cruzio.com> wrote:
>> On Tue, 18 Jan 2022 06:27:35 +0700, John B. <slocombjb@gmail.com>
>> wrote:
>>
>>> Yes, I tried one, belonging to a co-worker and I guess my brain
>>> doesn't work the way that HP does. Enter 1,3, divide doesn't seem
>>> logical, to me anyway (:-)
>>
>> Try instead: 1 Enter 3 Divide
>>
>> RPM works nicely for me because all I need to remember is to enter the
>> number first and then what I want to do with it (add subtract multiply
>> divide). Algebraic wants me to decide what I want to do with the
>> number before I enter it. That's not the way I think which is why I
>> prefer RPM notation. However, on single line display RPM calculators,
>> I still have problems remembering what I pushed into the stack
>> (sequentially accessed memory). I also learned algebraic before I
>> learned RPM, making unlearning algebraic.

>Not to sound to ignorant but don’t you mean RPN as in reverse Polish
>notation?

Oops. It's RPN, not RPM. I've been having a bit of a memory problem
recently. Not sure what's causing it. Last time, it was a bad
prescription causing a drug overdose. No clue yet this time. The
major problem was failing to remember dates and numbers correctly. I
try to double check those, but never considered that an acronym would
be involved.

Thanks for catching my mistake.

--
Jeff Liebermann jeffl@cruzio.com
PO Box 272 http://www.LearnByDestroying.com
Ben Lomond CA 95005-0272
Skype: JeffLiebermann AE6KS 831-336-2558

On Wednesday, January 19, 2022 at 9:39:10 AM UTC-8, jeff.li...@gmail.com wrote:
> On Wed, 19 Jan 2022 12:45:57 -0000 (UTC), Duane
> <no_e...@invalid.invalid> wrote:
>
> >Jeff Liebermann <je...@cruzio.com> wrote:
> >> On Tue, 18 Jan 2022 06:27:35 +0700, John B. <sloc...@gmail.com>
> >> wrote:
> >>
> >>> Yes, I tried one, belonging to a co-worker and I guess my brain
> >>> doesn't work the way that HP does. Enter 1,3, divide doesn't seem
> >>> logical, to me anyway (:-)
> >>
> >> Try instead: 1 Enter 3 Divide
> >>
> >> RPM works nicely for me because all I need to remember is to enter the
> >> number first and then what I want to do with it (add subtract multiply
> >> divide). Algebraic wants me to decide what I want to do with the
> >> number before I enter it. That's not the way I think which is why I
> >> prefer RPM notation. However, on single line display RPM calculators,
> >> I still have problems remembering what I pushed into the stack
> >> (sequentially accessed memory). I also learned algebraic before I
> >> learned RPM, making unlearning algebraic.
>
> >Not to sound to ignorant but don’t you mean RPN as in reverse Polish
> >notation?
> Oops. It's RPN, not RPM. I've been having a bit of a memory problem
> recently. Not sure what's causing it. Last time, it was a bad
> prescription causing a drug overdose. No clue yet this time. The
> major problem was failing to remember dates and numbers correctly. I
> try to double check those, but never considered that an acronym would
> be involved.
>
> Thanks for catching my mistake.

Typos, most especially those that are very easy to commit such as RPM rather than the discussed RPN aren't worth being corrected.

On Wed, 19 Jan 2022 06:15:59 -0800 (PST), "funkma...@hotmail.com"
<funkmasterxx@hotmail.com> wrote:

>On Wednesday, January 19, 2022 at 8:55:47 AM UTC-5, AMuzi wrote:
>> Mr Krygowski finds it intuitive.

>Many people do, though not me. I can do it, I just don't like it. Too many years of PEMDAS.

If you can function in both metric and imperial units, you should be
able to switch back and forth between algebraic and RPN(1) notation on
a calculator. If I can do it, anyone can. (How's that for arrogance?)
However, there are problems. I can switch methods on a calculator,
but can't do it when I'm trying to do math in my head or on paper.
When I do the math in my head, it's a visual representation of what I
would scribble on paper.

There are 3 systems of writing arithmetic expressions on paper:
<https://www.tutorialspoint.com/prefix-and-postfix-expressions-in-data-structure>
Algebraic is infix, RPN is postfix, and Polish Notation (not reversed)
is prefix. Computers don't really like algebraic (infix) notation:
"...it is not a very efficient way to design an algorithm
or program to parse infix notations. Instead, these infix
notations are first converted into either postfix or prefix
notations and then computed."

We tend to use whatever we learn FIRST. Undoing good or bad habits is
difficult. For example, I'm normally right handed. When I was about
10 years old, I found a bow and some arrows and proceeded to teach
myself how to use them (by watching westerns on TV). The problem was
that I learned using a left handed bow. When I entered college, I
took an archery class. That's when I discovered that I was doing it
all wrong for the previous 9 years. Attempts to switch to right
handed failed and continue to fail to this day.

I repeated the above mistake when I salvaged a free bicycle at age 16.
It was in bad shape, so I first tore it apart and cleaned everything.
When I re-assembled it, I goofed and reversed the front and rear brake
levers. I rode it to skool like that for about 6 months. When I
discovered the error, and switched the brake levers to the correct
positions, it took me a week or two to adjust.

(1) I initially typed RPM instead of RPN. I just added RPN into my
spelling chequer. Hopefully, that will help until I deal with my
problem.

--
Jeff Liebermann jeffl@cruzio.com
PO Box 272 http://www.LearnByDestroying.com
Ben Lomond CA 95005-0272
Skype: JeffLiebermann AE6KS 831-336-2558

On Tue, 18 Jan 2022 18:45:02 -0600, AMuzi <am@yellowjersey.org> wrote:

>On 1/18/2022 3:59 PM, Jeff Liebermann wrote:
>> On Tue, 18 Jan 2022 07:51:09 -0600, AMuzi <am@yellowjersey.org> wrote:
>>
>>> On 1/17/2022 11:21 PM, Jeff Liebermann wrote:
>>>> On Sun, 16 Jan 2022 22:45:18 -0800 (PST), Sir Ridesalot
>>>> <i_am_cycle_pathic@yahoo.ca> wrote:
>>>>
>>>>> A lot of people find it quite hard to shift properly with downtube shifters.
>>>>
>>>> I learned to ride using friction shifters, when there was little else
>>>> available that was afordable. Not knowing any better, I became fairly
>>>> proficient using them:
>>>> <http://www.learnbydestroying.com/jeffl/pics/bicycles/Miyata-610.JPG>
>>>> <http://www.learnbydestroying.com/jeffl/pics/bicycles/Trek-1400.JPG>
>>>> Note the downtube shifters. Learning to overshift and release back
>>>> slightly to take up the backlash and cable "stretch" was a bit tricky,
>>>> but eventually became instinctive.
>>
>>> Trek 1400 friction?
>>> Trek's first aluminum model, 2000, was in 1985. Later
>>> aluminum USA models were all index shift including 1400.
>>
>> You might be right, but as I recall, it was a friction shifter. It's
>> been too many years since I rode it. I don't have a clue as to the
>> year. There's was only a "D" ring to adjust the pressure. I no
>> longer have the bicycle (the frame was too small for me) so I can't
>> easily check the shifters. Enlarging the photo, it looks like the
>> rear derailleur is Shimano 105. The front shifters are something like
>> these:
>> <https://www.ebay.com/itm/203792913384>
>> I don't recall how many speeds and can't easily count the sprokets
>> from my photo.
>>
>> I did some Googling and found a 1991 Trek 1400 with friction shifters:
>> <https://bikeindex.org/bikes/663207>
>> "Shift And Brake Lever Down-tube friction (non-index)
>> shifters. Bright silver Dynasys ()"
>>
>> Incidentally, this was the bicycle that gave me trouble from my toes
>> hitting the trailing edge of the front wheel in a turn.

>The red bike at bikeindex is almost all not-original parts.

I found some more photos of White Trek 1400 bicycles:
<https://www.google.com/search?q=1989+trek+1400+white+friction&tbm=isch>
I went through the first 20 pages and didn't find a match that
described the type of shifter. I did find several 1990 models, with
indexed shifting. For example:
<https://www.facebook.com/RLBcycle/posts/this-is-a-classic-1990-trek-1400-racing-road-bike-made-in-usa-rare-small-frame-m/1055519977954536/>
It's quite possible that the 1989 and 1990 models are similar.

>Model 1400 was only 1989 and later and there were no
>friction (factory) road bikes in 1989:
>http://vintage-trek.com/model_numbers1.htm

"89, intense blue with white decals, also white with red decals"
More 1989 info, but nothing on the shifters:
<http://www.vintage-trek.com/Trekpromoa.htm#pg19>
I couldn't find a 1989 Trek road bicycle catalog.

As I previous mumbled, you might be right. You know far more about
such bicycles than I. However, I still recall that it used friction
shifters. If I had to make a determination at this point (to save
time), I would probably concede that it probably used indexed shifting
and that my memory is faulty. I've sent an email to the father of the
current owner of the bicycle for a determination.

Thanks for the likely correction.
--
Jeff Liebermann jeffl@cruzio.com
PO Box 272 http://www.LearnByDestroying.com
Ben Lomond CA 95005-0272
Skype: JeffLiebermann AE6KS 831-336-2558

On Wednesday, January 19, 2022 at 10:54:18 AM UTC-8, jeff.li...@gmail.com wrote:
> On Tue, 18 Jan 2022 18:45:02 -0600, AMuzi <a...@yellowjersey.org> wrote:
>
> >On 1/18/2022 3:59 PM, Jeff Liebermann wrote:
> >> On Tue, 18 Jan 2022 07:51:09 -0600, AMuzi <a...@yellowjersey.org> wrote:
> >>
> >>> On 1/17/2022 11:21 PM, Jeff Liebermann wrote:
> >>>> On Sun, 16 Jan 2022 22:45:18 -0800 (PST), Sir Ridesalot
> >>>> <i_am_cyc...@yahoo.ca> wrote:
> >>>>
> >>>>> A lot of people find it quite hard to shift properly with downtube shifters.
> >>>>
> >>>> I learned to ride using friction shifters, when there was little else
> >>>> available that was afordable. Not knowing any better, I became fairly
> >>>> proficient using them:
> >>>> <http://www.learnbydestroying.com/jeffl/pics/bicycles/Miyata-610.JPG>
> >>>> <http://www.learnbydestroying.com/jeffl/pics/bicycles/Trek-1400.JPG>
> >>>> Note the downtube shifters. Learning to overshift and release back
> >>>> slightly to take up the backlash and cable "stretch" was a bit tricky,
> >>>> but eventually became instinctive.
> >>
> >>> Trek 1400 friction?
> >>> Trek's first aluminum model, 2000, was in 1985. Later
> >>> aluminum USA models were all index shift including 1400.
> >>
> >> You might be right, but as I recall, it was a friction shifter. It's
> >> been too many years since I rode it. I don't have a clue as to the
> >> year. There's was only a "D" ring to adjust the pressure. I no
> >> longer have the bicycle (the frame was too small for me) so I can't
> >> easily check the shifters. Enlarging the photo, it looks like the
> >> rear derailleur is Shimano 105. The front shifters are something like
> >> these:
> >> <https://www.ebay.com/itm/203792913384>
> >> I don't recall how many speeds and can't easily count the sprokets
> >> from my photo.
> >>
> >> I did some Googling and found a 1991 Trek 1400 with friction shifters:
> >> <https://bikeindex.org/bikes/663207>
> >> "Shift And Brake Lever Down-tube friction (non-index)
> >> shifters. Bright silver Dynasys ()"
> >>
> >> Incidentally, this was the bicycle that gave me trouble from my toes
> >> hitting the trailing edge of the front wheel in a turn.
>
> >The red bike at bikeindex is almost all not-original parts.
> I found some more photos of White Trek 1400 bicycles:
> <https://www.google.com/search?q=1989+trek+1400+white+friction&tbm=isch>
> I went through the first 20 pages and didn't find a match that
> described the type of shifter. I did find several 1990 models, with
> indexed shifting. For example:
> <https://www.facebook.com/RLBcycle/posts/this-is-a-classic-1990-trek-1400-racing-road-bike-made-in-usa-rare-small-frame-m/1055519977954536/>
> It's quite possible that the 1989 and 1990 models are similar.
> >Model 1400 was only 1989 and later and there were no
> >friction (factory) road bikes in 1989:
> >http://vintage-trek.com/model_numbers1.htm
> "89, intense blue with white decals, also white with red decals"
> More 1989 info, but nothing on the shifters:
> <http://www.vintage-trek.com/Trekpromoa.htm#pg19>
> I couldn't find a 1989 Trek road bicycle catalog.
>
> As I previous mumbled, you might be right. You know far more about
> such bicycles than I. However, I still recall that it used friction
> shifters. If I had to make a determination at this point (to save
> time), I would probably concede that it probably used indexed shifting
> and that my memory is faulty. I've sent an email to the father of the
> current owner of the bicycle for a determination.
>
> Thanks for the likely correction.

I removed the Campy Centaur 10 speed levers from the Douglas Vector and installed the Record 10 speed first generation levers. I had forgotten how that far more direct cable routing made the shifting absolutely effortless. And I cabled it with new Campagnolo cables so that they won't stretch. So they should remain in perfect order for the new owner. I took it out on a 25 miler before relisting it in its new configuration. I was pretty impressed since the Douglas is an extremely smooth riding bike and the Record 10 speeds gives you enough.