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2019-04-07 11:24:59 +0100 commented answer How can I retrieve sage worksheets from old hard drive

Unfortunately I have already created some new worksheets.

2019-03-29 16:59:35 +0100 asked a question How can I retrieve sage worksheets from old hard drive

Recently, my computer (a Macbook Pro) stopped working suddenly. I have now replaced it with a newer Macbook Pro, and I would like to get my sage worksheets from my previous computer onto my new one. The drive on the old computer is fine and I have access to everything on it, but I do not know where the sage worksheets are stored. According to this: https://ask.sagemath.org/question/865... they should be in the directory ~/.sage/sage_notebook.sagenb/home/. I have copied the .sage directory from my old hard drive to my new one. Inside there is indeed a directory called sage_notebook.sagenb and inside that there is a directory called home. Inside home is a folder named __store__, and then three shortcuts (I think they are shortcuts, they are little folders with arrows in the bottom left corner) named admin, guest, and pub. Both guest and pub are empty. The contents of __store__ are mostly inscrutable. There are essentially three possible paths one can take:

/__store__/0/08/084/084e/guest/ which is empty

/__store__/3/3a/3a2/3a21/pub/ which is empty

/__store__/2/21/212/2123/admin/ which is filled with folders 0 through 34 and a file called history.pickle

Inside each of the folders labeled 0 through 34 are two folders named cells and data and two files named worksheet_conf.pickle and worksheet.html. The data and cells folders are sometimes empty but other times data contains some of my .sobj files and cells contains one or many folders labelled by seemingly random numbers. Inside these folders are files of various types, I think I have seen .sobj, .png, and .txt files so far.

What do I do so that when I run notebook() in a sage terminal and it opens up a browser window with all of my worksheets listed I will be able to see the worksheets that I had on my previous computer?

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2019-03-26 15:42:56 +0100 answered a question How do I install a GAP package in Sage?

In the end I did the following and it seems to have worked:

I went here: http://www.cecm.sfu.ca/sage/spkg/upst... and downloaded the version of GAP 4.10 from there that already has io and orb and digraphs in it. Then I replaced the gap folder in /Applications/SageMath/local/share/ with this new gap folder. I opened a terminal at this new gap folder and ran "./configure" and then "make". Then I opened a terminal at the io folder inside this new gap folder and ran "./configure" and then "make", and then did the same at the digraphs folder.

2019-03-26 11:41:20 +0100 commented answer How do I install a GAP package in Sage?

But if I now write

gap.eval('LoadPackage("io")')

in a sage worksheet, then it says "fail", rather than "true" which is what it says if for instance I write

gap.eval('LoadPackage("sonata")')

2019-03-26 01:03:43 +0100 commented answer How do I install a GAP package in Sage?

Okay, I did that, but I still get the same error when running make.

2019-03-25 20:58:00 +0100 asked a question How do I install a GAP package in Sage?

I would like to install the package DiGraphs (https://www.gap-system.org/Packages/d...) into the GAP version that is part of Sage. I just installed the latest version of Sage, Sage 8.6, on a Mac. There is a page about doing this here: https://wiki.sagemath.org/InstallingG... but you will notice that at the top it says "Since GAP 4.10 release, in Sage 8.6 (Jan 2019), you should not use the following instructions!" Of course it offers no alternatives. The readme for the DiGraphs says that you should have the GAP packages IO and orb installed. I am not able to install the IO package, which I downloaded from here: https://www.gap-system.org/Packages/i... and then put in the folder where the other GAP packages are, namely Applications/SageMath/local/share/gap/pkg/

The readme file for the IO package says to change directories to the folder containing the IO package and then run "./configure", which I have done. Next it says to run "make", but this gives me the following error:

src/io.c:14:10: fatal error: 'src/compiled.h' file not found

#include "src/compiled.h" /* GAP headers */

Can anyone help me with this? I have had the DiGraphs package installed within GAP inside of Sage previously, but I recently got a new computer and had to reinstall everything, and it seems certain things have changed with the new version of Sage.

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2016-06-01 16:53:11 +0100 asked a question Bug in cos function in version 7.2

I have 'SageMath version 7.2, Release Date: 2016-05-15' and when I enter cos(pi*(1+(5/63))) it returns cos(5/63*pi) which is incorrect (there should be a negative sign in front). Entering cos(N(pi)*(1+(5/63))) returns -0.969077286229078 which is correct, but entering N(cos(pi\*(1+(5/63)))) returns 0.969077286229078. Similar things happen when 5/63 is replaced with other fractions, but not always. Usually if the fraction is "nice", like 1/4 or 1/5 then it seems to get the right answer. I assume this has something to do with the exact answer being able to be expressed nicely with square roots, but I don't really know. Same happens with sin as far as I can tell. Anybody else having this problem?

2016-06-01 16:53:10 +0100 asked a question cos function is wrong in 7.2

I have 'SageMath version 7.2, Release Date: 2016-05-15' and when I enter cos(pi(1+(5/63))) it returns cos(5/63pi) which is incorrect (there should be a negative sign in front). Entering cos(N(pi)(1+(5/63))) returns -0.969077286229078 which is correct, but entering N(cos(pi(1+(5/63)))) returns 0.969077286229078. Similar things happen when 5/63 is replaced with other fractions, but not always. Usually if the fraction is "nice", like 1/4 or 1/5 then it seems to get the right answer. I assume this has something to do with the exact answer being able to be expressed nicely with square roots, but I don't really know. Same happens with sin as far as I can tell. Anybody else having this problem?

2015-11-03 05:58:21 +0100 asked a question How to update the GAP version Sage is using

I am trying to use a certain Gap package which requires Gap version 4.7.8 to work, but my version of Sage (which I believe is the latest non-beta version) only has Gap 4.7.5. I was wondering if there is a way to update the version of Gap that Sage is using. I can just get a standalone version of GAP, but I'd rather be able to do everything I want to do within Sage, so I don't have to keep switching back and forth between the two.