Is it possible to hide the CellLabels
Out[n]= in a Mathematica notebook?
I don't want to hide the input or output, just the text
There's an option "Show In/Out Names" in the preferences (Edit menu -> Preferences) under Evaluation.
It takes effect right away in the notebooks I already have open.
Out parts of the Mathematica notebook are automatically generated CellLabels for evaluated Input and generated Output cells. Since the numbering refers to the current kernel session, the labels are set to delete when you close the notebook (the cell styles have the option
CellLabelAutoDelete -> True). So one solution is to close and then reopen the notebook before printing.
All of the following methods turn off all CellLabels, not just the In/Out ones.
(As mentioned in rakslice's answer)
Use the "Show In/Out Names" toggle in the preferences dialog. This sets the option
ShowCellLabel->False globally, i.e. it turns off all CellLabels for all notebooks.
The option can also be set at a notebook, section or cell level (or globally) using the option inspector. For example, in the following screenshot I've turned off the cell labels for "Untitled 1" but left them on for "Untitled 2": screenshot http://fhc.quickmediasolutions.com/image/-167608879.png
Go to Format > Edit Stylesheet. You'll get the blank, top-level stylesheet for the notebook you're working on. It inherits its styles from the "default.nb" stylesheet. Click on that link and copy the
Style Environment Names section to the stylesheet of the notebook. Select the cell bracket for the "Printout" environment cell and using the option inspector (Ctrl-Shift-O) (or by modifying the cell expression Ctrl-Shift-E) set the option
You could also create your own stylesheet to use in other notebooks or even change the default stylesheet to reflect your preferences.
Programmatically (IMO the fastest way to do it), use
SetOptions[$FrontEnd, ShowCellLabel -> False]
Doing it like this (or via the Option Inspector) is necessary starting in version 11.1.1, since the Evaluation preferences tab is gone.
You can also change it for just