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Meaning of three vertical dots between factors in a Notebook line of output

In a long output whose lines consist of products of circular functions and variable names, three vertical dots sometimes appear  between variable names  and a Cos[ ] or Sin[ ].  The occurence appears to be random as I can detect no systematic constraint on their location.  E.g. K (three dots in a vertical arrangement like a colon) Cos.  What is the meaning of the vertical dots? Missing material? or can they be ignored?  If the latter, why are they there?
POSTED BY: Stanton Peale
21 Replies
It would help if you could give an explicit example of a Mathematica input that yields this output.
POSTED BY: David Reiss
I could not find a simple espression that would yield the vertical dots.  I did find some additional information outside of Mathematica.  The three vertical dots is called a vertical ellipsis, and like the ordinary ellipsis (...) it indicates that something has been omitted.   If this is the meaning in Mathematica, I must find out how retrieve the factors that were omitted.   The vertical ellipsis first appeared in a very long trigonometric expression that involved orthogonal transformations between three coordinate systems, where the transformations are expressed in terms of three sets of Euler angles.  Expand [ ]  or TrigExpand[ ] do not eliminate the vertical ellipses and seems to introduce additional ones.

If my interpretation of the vertical ellipsis is correct, how do I find what the factors are that have been omitted?  I found nothing in the online Mathematica manual.
POSTED BY: Stanton Peale
Is it possible \ [VerticalEllipsis ] or similar was entered in the notebook by accident? Note that Mathematica will do computations with it, just as with any other symbol.
In[3]:= TrigExpand[Sin[\[VerticalEllipsis] + \[VerticalEllipsis]]]

Out[3]= 2 Cos[\[VerticalEllipsis]] Sin[\[VerticalEllipsis]]
POSTED BY: Ilian Gachevski
No, there was no introduction of  VerticalEllipsis  into the notebook.  The input that genrated the output containing the Vertical Ellipses was simply the multiplication of trigonometric functons.   The operation you show involving the VerticalEllipsis[ ] command is meaningless unless one knows what the Vertical Ellipsis represents. I am now seeking to find out what the vertical ellipses mean in my output.  I must know this in order to use the output in subsequent operations.
S.
 
POSTED BY: Stanton Peale
 
It might be much easier to see what the issue is if you could add your notebook (as an attachment) here, or upload it somewhere and give a link.
POSTED BY: Ilian Gachevski
Yes, quite hard to a diagnosis without an example unfortunately. 
POSTED BY: David Reiss
I copied the first nine pages of my notebook into a pdf file.  The VerticalEllipsis appears first in the line in torq1 that begins with 2 alfs, which is a few lines down from the beginning of torq1.  I have attached the file partofmath013014nb.pdf.
POSTED BY: Stanton Peale
I do not see the file anywhere, so I am not sure it was attached successfully. Here is another try.
POSTED BY: Stanton Peale
Still no file. How do I access the attached file?
POSTED BY: Stanton Peale
Dear Stanton, it does not seem that you actually successfully attaching the file.

We attached a test file to this post so you can see where it suppose to appear.

Please try fully supported web-browsers: Chrome, Firefox or Safari.
Attachments:
POSTED BY: EDITORIAL BOARD
The file i tried to attach was a pdf file.  Can it be that the site only accepts .nb files?  Is there a way to attach a pdf file?  The reason for the pdf file is that the .nb file from which it is extracted is 387 pages long.  I am a novice at Mathematica, so I do not know how to extract part of an .nb file into a separate .nb file. I will make another attempt to attach the pdf file.
POSTED BY: Stanton Peale
The file failed to attach, so I am somehow missing some steps in the attachement process.  Clicking on "add a file to this post" brings up a window with the directory containing the file.  Opening the file places the file name under the "Attachments".  Clicking on "publish"  sends this text, but without the attached file. What am I missing.
POSTED BY: Stanton Peale
PDF files can be attached - see example in this post.

Only file sizes less than 20 MB can be attached.
Attachments:
POSTED BY: EDITORIAL BOARD
Sorry about the problems attaching a file.  They are believed to have been fixed yesterday afternoon.  Please try again.
POSTED BY: Bruce Miller
By the way, a screenshot of a page from your notebook that shows the issue would also be of use.  300 pages of a notebook may be a bit of overkill.  
POSTED BY: David Reiss
Ok, here goes again.   For those following this discussion, the pdf file partofmath013014nb.pdf is the first 9 pages of a very long nb file.  The first vertical ellipsis encountered in the output is at Out[54] 12 lines down in the definition of torq1.  This file is simply the result of multipication of circular functions and should be straightforward. But the vertical ellipsis appears mysteriously, and I can find out nothing about it on the Mathematica web pages.  What does it mean?  If it means omitted material, how do I find out what the missing terms are?  The pdf file is attached.  I hope it goes through this time.
Attachments:
POSTED BY: Stanton Peale
Check your In[50], it seems that the mystery symbol is typed in there.
POSTED BY: Ilian Gachevski
Is it the same symbol you get when you press the ESC key?
POSTED BY: Szabolcs Horvát
Actually yes, these are not really dots.  Looks like \[ AliasDelimiter].
POSTED BY: Ilian Gachevski
The symbol is in fact that produced by the escape key.  Ilian Gachevski spotted the symbol in In[50], where I must have hit the excape key by mistake.  I would never have noticed that.  Thanks, Illian.  The symbol is carried through subsequent calculations as a factor, just as it appears at In[50].  Is it safe just to erase this symbol where it appears, or should I redo all the calculations after removing the symbol at In[50]?  I think the latter procedure may be the safest.  Now I will go to the web manual to find out what "escape" means and where it is used.   Thanks to everyone for your interest and for solving the problem.  Who knew about the escape key? 
POSTED BY: Stanton Peale
One way you might have found this yourself would have been to copy the symbol from where you first noticed it in the output and then searched for that symbol starting from the top of the notebook to see where it first appeared.  

If  the Mathematica session in which these computaitons were done is still active then you can remove the symbol from In[50] and execute the remainder of the notebook from there.  If however you've quit Mathematica then you need to do the full computation starting from the beginning. 
POSTED BY: David Reiss
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