Seeking for method to speedup and get more flexable control Notebook History

Question

When doing calculations in notebook, I modify the code a lot, and there are several versions of similar codes in the same notebook. But I found myself easily forgot which version is the newest, and I have to confirm which cell is the newest.

So if mathematica can provide a menu options like "cell latest modification time" will be useful. But now, I can't find this option.

However, mathematica provide a menu option "Cell-> Notebook History" can do this job.

The problem is that on my computer, mathematica ver 10.3, if the notebook has a long and rich history, then the Notebook History makes mma froze again and again, keep popping dialog of "Formatting Notebook Contents" as follows

How can I start the notebook history for example only recent 3 days or more generally between specific date 10 Nov to 13 Nov? And also how to start notebook history with selected cell as default?

Answer 1

From the OPs comments I deduce that the problem is only the dialog that opens when one opens with the menu entry "Cell" -> "Notebook History" and which shows a relatively involved visualization of the history and defaults to analyze the whole notebook. Obviously that is too slow for really large notebooks. But if one only is interested in the last change of a single cell, one can use code like the following to just get that information, and I'd guess that this should work even for huge notebooks as long as these still work in general.

Here is the code which generates a palette with one button which shows the last change time for the selected cell(s):

CreatePalette@Button["Show Last Cell-Change", MessageDialog[
 SelectionMove[InputNotebook[], All, Cell];
  Grid[
  MapIndexed[Flatten[{#2, #1}] &, Replace[
  Cases[{NotebookRead[InputNotebook[]]}, Cell[___], Infinity], {
   Cell[___, CellChangeTimes -> t_] :> DateString[Max[t]+3600*$TimeZone],
   Cell[___] :> None
   }, {1}]
 ]
 ]
], Method -> "Queued"]

for the interested here is what it does: The notebook history feature can be switched on either globally with Edit -> Preferences -> Advanced -> "Enable notebook history tracking" or just for the current notebook with e.g. SetOptions[EvaluationNotebook[],TrackCellChangeTimes -> True]. Once that settings has been made, the Mathmatica FrontEnd adds timestamps to cells when these are edited. These timestamps are aggregated within the Cell-Option CellChangeTimes. What my code does is to just extract that information which is in the form of timestamps as given by AbsoluteTime[] but obviously for UTC that is TimeZone->0. The Max of all those values is the last time the cell has changed and that is shown in human readable form with DateString. I have adjusted for the time zone in a somewhat ad hoc way which I have not tested for other timezones than my own but think should work. I could imagine that other things would also need improvement but it should basically work, show the idea and I would expect it to not create problems when a notebook gets large or the history is long.

EDIT

As the OP has mentioned in comments he is still searching for a way to change the default setting for the selection toggle. While a programmatic change of that might be possible it would certainly be somewhat involved and "dirty". On the other side it seems to be easy enough to just edit the system dialog definition which one can find here:

What you could do is to replace the default palette notebook which you can find here:

FileNameJoin[{$InstallationDirectory, "SystemFiles", "FrontEnd", 
  "SystemResources", "HistoryOverview.nb"}] 

with one where the corresponding default settings is changed. To do that, I would suggest to:

1. make a copy of that notebook
2. open the copy in a text editor
3. replace $CellContext`selectionOnly$$ = False with $CellContext`selectionOnly$$ = True
4. safe the file

5. open the edited file in mathematica and save it (to avoid messages about it being edited outside of mathematica). As the notebook has settings specific to palettes it can only be saved programmatically. To do that, you have to get a handle to the corresponding notebook object and then call NotebookSave for that. The following code will do that:

   NotebookSave[
    First[Select[
      Notebooks[], 
      Not[FreeQ[CurrentValue[#, WindowTitle], "HistoryOverviewDialog"]] &]
    ]
   ]
   

6. replace the original notebook with the edited one, probably making a backup copy of the original before that.

the last step (replacing that file in $InstallationDirectory) will of course only be possible with corresponding file permissions.

If you now restart mathematica the history overview dialog should now open always with the "selection only" setting...

Answer 2

Albert Retey just created a great button that can give a cell's latest modification time directly.

Here is a another workaround. It is small trick I just found, but works perfectly : )

The frozen of mma when open Notebook History windows is due to the default setting is checked for "All cell" instead of "selected cell". So mma collecting too many data to analysis dynamically.

If we could make "selected cell" the default option, then we solve the problem. But I don't know how to do it.

Anyway, here is the "bug" trick.

First, you have to open a fresh new notebook.

second, in this new notebook, you open Notebook History window, and check the "selected cell" option. like this

Third, switch back to the large notebook, now since "Notebook History window" is already set to analyze only selected cell, frozen problem is solved and you can select any cell to see its history smoothly without lag.