Re: Basic Question about Mathematica

*To*: mathgroup at smc.vnet.net*Subject*: [mg83386] Re: Basic Question about Mathematica*From*: Bill Rowe <readnewsciv at sbcglobal.net>*Date*: Mon, 19 Nov 2007 06:12:25 -0500 (EST)

On 11/18/07 at 4:54 AM, dmartin19 at gmail.com wrote: >I was working in a notebook, using help files to try to learn >Mathematica. I noticed that Mathematica uses cells for entry, and >each of my entries in a cell are tagged by numbers, such as "In[n]" >and "Out[n]" where "n" is some number. >Being new, I keep making a lot of mistakes while experimenting, and >each time when I realize the mistake, I delete the cell and start >over again. When I do this, Mathematica does not continue to number >the "In[n]" and "Out[n]" lines sequentially based on what is >actually on the notebook, but instead remembers the numbers from the >deleted cells even after I have deleted them. >Consequently, with only 10 or so cells on my notebook, I have >numbers like "In[102]" because Mathematica is remembering all the >deletions, and all the times I asked it to recalculate. >What is worse is that it seems to remember errors and variables from >the deleted cells. If I previously made a mistake with some variable >or expression and deleted it, then tried to define it again, it >gives me the same error I got before I deleted it. >Clearing the history does not help. >Is there any way to get Mathematica to totally forget stuff that I >have deleted and only evaluate whatever is in the notebook at a >given time? Yes. The function ClearInOut in the package CleanSlate that can be found at <http://library.wolfram.com/infocenter/MathSource/4718/> will help. This function will clear the history and reset the In/Out numbers. But it will not execute any of the other cells you want executed automatically. You will have to re-execute these yourself. >It would also be great if it could renumber the "In[n]" and "Out[n]" >statements so they bear some semblance to the actual number of cells >in my notebook. There probably is a way to accomplish with some programming. But this isn't likely to be a simple thing to do. And I expect in the final analysis it will not be desirable. -- To reply via email subtract one hundred and four