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From: Murray Eisenberg on 6 Jul 2010 05:03
Actually, I think here the default -- to have the More Information group
closed -- is quite reasonable. So that what you see is the brief
Information output cell near the top and the EXAMPLES group initially open.

I've spent a lot of time watching Mathematica beginners learn, and
there's no question that most of them instinctively head first for
examples and only afterward (if at all) looking for an actual description.

If you want to open all the closed groups in _any_ window, including a
window inside the Help Browser, after being sure that window has the
focus, you can do it with the menu:

Edit > Select All
Cell > Grouping > Open All Subgroups

And the menu items will show you which keyboard shortcuts to use on your
platform.

On 7/5/2010 9:15 PM, AES wrote:
> In article<i0saj2$eno$1(a)smc.vnet.net>,
> "Nasser M. Abbasi"<nma(a)12000.org> wrote:
>
>>
>> My lesson of the day: do not use TraditionalForm inside expressions.
>>
>
> Another example of what some of us call a "gotcha".
>
> To its credit, Wolfram gives a kind of semi-explicit warning about this
> particular gotcha as the first item in the "More Information" cell that
> comes right after the initial short command summary in the
> "ref/TraditionalForm" Help window. But:
>
> 1) Your wording is a lot more terse, and will be much clearer and more
> helpful for novice users, than Wolfram's.
>
> 2) And, this More Information cell is, for some reason, closed by
> default when the ref/TraditionalForm window is opened.
>
> I can get from a notebook cell to a ref/Xxxx Help window (and back)
> purely by keyboard commands on my extended Mac keyboard -- but I don't
> know how to then open the More Information cells except by going to the
> mouse and futzing with it.
>
> Seems to me the default for the More Information cells ought to be that
> they're open when any ref/Xxxx window is opened. Any way to set that
> default for all ref/Xxxx (and similar) windows?
>
> (And while we're at it, any keyboard way to open _all_ the subsequent
> closed section-heading cells in a ref/Xxxx window at once, so that
> powerful Find or Search capabilities could be used in some of these very
> lengthy Help windows?)
>

--
Murray Eisenberg murray(a)math.umass.edu
Mathematics & Statistics Dept.
Lederle Graduate Research Tower phone 413 549-1020 (H)
University of Massachusetts 413 545-2859 (W)
710 North Pleasant Street fax 413 545-1801
Amherst, MA 01003-9305

From: AES on 7 Jul 2010 07:40
In article <i0urg4$6jp$1(a)smc.vnet.net>,
Murray Eisenberg <murray(a)math.umass.edu> wrote:

> If you want to open all the closed groups in _any_ window, including a
> window inside the Help Browser, after being sure that window has the
> focus, you can do it with the menu:
>
> Edit > Select All
> Cell > Grouping > Open All Subgroups
>
> And the menu items will show you which keyboard shortcuts to use on your
> platform.

Following is on Mac using Tiger and Mathematica 7:

If I type a command -- e.g., "TraditionalForm" -- in a notebook cell and
hit Cmd-Shift-F (or Help key on extended keyboard), Help Browser opens
with focus in the Search field at the top of the window.

Haven't found a key command to get focus from there into anywhere in the
window itself: Arrow keys, Tab key, Cmd-A, don't seem to do it. ???

Mouse click will shift focus to the Help Browser window, but you have to
be careful to either click between cells, or after clicking use Arrow
keys to get cursor between cells.

Cmd-A will then select all cells (or groups), and Cmd-Shift-{ will open
all of them.

So, four (or 5+) key commands and one mouse click to get from notebook
cell to More Info items this way. I'd prefer having More Info be open
by default when Help Browser window opens, meaning _one_ key command
from notebook cell to More Info info.

More Info list is usually pretty short; the Examples header and start of
example cells is generally visible below it on the initial screen. And
it's the natural place to alert first-time info seekers to gotchas or
other warnings, for those few Mathematica commands that may need such
warnings.

From: Bill Rowe on 7 Jul 2010 07:40
On 7/6/10 at 5:03 AM, murray(a)math.umass.edu (Murray Eisenberg) wrote:

>If you want to open all the closed groups in _any_ window, including
>a window inside the Help Browser, after being sure that window has
>the focus, you can do it with the menu:

>Edit > Select All
>Cell > Grouping > Open All Subgroups

>And the menu items will show you which keyboard shortcuts to use on
>your platform.

On a Mac, the approach you describe above doesn't seem possible
without using the mouse. The issue is when the Help Browser page
is appears, the focus is on the search input box. Consequently,
the key stroke to Select All selects the contents of the search
box rather than all of the cells. Clicking the mouse once on the
window anywhere except the search box causes the focus to
change. Now all of the cells can be selected and opened using
key strokes.


From: Leonid Shifrin on 8 Jul 2010 03:12
The statement from the Help regarding Unevaluated may be incomplete, but at
least it is precise.
To understand what the "argument of the function" part means, one has to
study main evaluation loop in greater detail than is appropriate for the
majority of users. To omit this part however would mean to
give imprecise information.

What really happens is that Unevaluated wrappers are temporarily discarded
during evaluation for those parts of expression which evaluator reaches in
the course of evaluation, but then, if no rules were applied to those parts
or their subparts, they are restored at the end of this evaluation
(Unevaluated wrappers are not stripped as a result). This is what happens,
in particular, when Unevaluated[something] is not an argument to a
function. And no, Unevaluated[expr] does not have to always be an argument
of a function - it can be a stand-alone expression.

The trade - off that documentation writers face in this and similar cases is
between giving too many details (the above sketchy explanation would become
clear only in the context of a detailed discussion of the entire evaluation
loop), and making precise statements which may sound unclear to some users,
since the context in which they can be easily understood is not supplied.
This trade-off IMO simply reflects the nature of Mathematica as being a very
powerful system with multiple but overlapping target audiences. Perhaps, in
time the documentation may evolve to have a layered structure reflecting
this, with briefer layers giving references to more in-depth descriptions.
We actually do see this starting to happen already with the "More
information" sections - it just needs time.

Meanwhile, it looks like in this particular case (with respect to this
particular topic) you were unlucky to be in such an overlap group of users -
the users who do pay attention to this detail of the documentation (most
don't), but are not aware of its meaning. If you are particularly interested
in this specific topic, two good accounts are a book of David Wagner and a
technical report of David Withoff named "Mathematica internals" (the latter
available free online). Given the kinds of topics you usually are willing
to discuss on the group, I think you would find these sources particularly
useful.

Hope this helps.

Regards,
Leonid





On Wed, Jul 7, 2010 at 3:42 PM, AES <siegman(a)stanford.edu> wrote:

> In article <i0urh5$6l9$1(a)smc.vnet.net>,
> Andrzej Kozlowski <akozlowski(a)gmail.com> wrote:
>
> > 1 + Unevaluated[1]
> >
> > 2
>
> Fascinating. I'd call this one more classic Mathematica gotcha, and one
> more example of fairly poor quality of Mathematica documentation -- or
> at least of the very arcane character of Mathematica for "ordinary
> users", once you get to any depth within it.
>
> Help Browser says:
>
> Unevaluated[expr]
> represents the unevaluated form of expr when it appears as
> the argument to a function.
>
> So, what does Unevaluated[expr] do when it is NOT the argument to a
> function?
>
> (The previous statement I'd say clearly implies that there are times
> when Unevaluated[expr] does appear as an arg to function, and therefore
> times when it does not -- and both need to be defined.)
>
> So, if Unevaluated[expr] is entered all by itself in a cell, is it then
> "the argument to a function"?
>
> If the cell contains 1 + Unevaluated[expr] as above, does that make the
> Unevaluated[expr] an argument to a function -- or not? (I can see
> arguing that above queries either way -- and digging further down into
> the Help Browser examples is not very helpful.)
>
> How would one find out from Mathematica documentation what "argument to
> a function" means, precisely? Is there any significance to "argument
> to" rather than the (I think) more common usage "argument of"?
>
> Is Unevaluated[expr] used in a syntactically acceptable way _always_ the
> argument to a function?
>
>
From: Murray Eisenberg on 8 Jul 2010 03:15
So a natural follow-up question would be: If you do not want the Help
key (etc.) to land you on the Search field in the Documentation Center
page, then where on the page itself should the cursor be?

I can see lots of arguments about that! For some users, the More
Information section. For others, the Examples section. So you'd still
need to use the mouse to navigate to the place in the page you wanted.

It's not a good answer to say that it doesn't matter where in the page
to land, since you want to open all subgroups anyway. That's just
_your_ preference. For my part, it's very seldom what I want to do.

On 7/7/2010 7:41 AM, AES wrote:
> In article<i0urg4$6jp$1(a)smc.vnet.net>,
> Murray Eisenberg<murray(a)math.umass.edu> wrote:
>
>> If you want to open all the closed groups in _any_ window, including a
>> window inside the Help Browser, after being sure that window has the
>> focus, you can do it with the menu:
>>
>> Edit> Select All
>> Cell> Grouping> Open All Subgroups
>>
>> And the menu items will show you which keyboard shortcuts to use on your
>> platform.
>
> Following is on Mac using Tiger and Mathematica 7:
>
> If I type a command -- e.g., "TraditionalForm" -- in a notebook cell and
> hit Cmd-Shift-F (or Help key on extended keyboard), Help Browser opens
> with focus in the Search field at the top of the window.
>
> Haven't found a key command to get focus from there into anywhere in the
> window itself: Arrow keys, Tab key, Cmd-A, don't seem to do it. ???
>
> Mouse click will shift focus to the Help Browser window, but you have to
> be careful to either click between cells, or after clicking use Arrow
> keys to get cursor between cells.
>
> Cmd-A will then select all cells (or groups), and Cmd-Shift-{ will open
> all of them.
>
> So, four (or 5+) key commands and one mouse click to get from notebook
> cell to More Info items this way. I'd prefer having More Info be open
> by default when Help Browser window opens, meaning _one_ key command
> from notebook cell to More Info info.
>
> More Info list is usually pretty short; the Examples header and start of
> example cells is generally visible below it on the initial screen. And
> it's the natural place to alert first-time info seekers to gotchas or
> other warnings, for those few Mathematica commands that may need such
> warnings.
>

--
Murray Eisenberg murray(a)math.umass.edu
Mathematics & Statistics Dept.
Lederle Graduate Research Tower phone 413 549-1020 (H)
University of Massachusetts 413 545-2859 (W)
710 North Pleasant Street fax 413 545-1801
Amherst, MA 01003-9305

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