[sage-support] Re: Why are these finite field elements not equal?
On Monday 02 April 2007 22:53, Kate Minola wrote: Would a kind person explain to me why element 1 and element 2 are not equal? And what I need to do to test if element 1 is zero in K? # setup f = conway_polynomial(2,63) K.a = GF(2**63, name='a', modulus=f) n = f.degree() m = 3; e = (2^n - 1) / (2^m - 1) c = a^e conway = conway_polynomial(2,m) # element 1 print conway(c) # says 0 print type(c) print parent(c) print c in K # says True # element 2 print K(0) # says 0 print type(K(0)) print parent(K(0)) print conway(c) == K(0)# says False??? This seems to be a bug in the pari.gen.gen class: sage: e1 = conway(c) sage: e2 = K(0) When compare is called on them, their pari values are compared, these differ in their representation. sage: e1._FiniteField_ext_pariElement__value 0 sage: e2._FiniteField_ext_pariElement__value Mod(Mod(0, 2), Mod(1, 2)*a^63 + Mod(1, 2)*a^24 + Mod(1, 2)*a^23 + Mod(1, 2)*a^22 + Mod(1, 2)*a^17 + Mod(1, 2)*a^16 + Mod(1, 2)*a^15 + Mod(1, 2)*a^11 + Mod(1, 2)*a^9 + Mod(1, 2)*a^8 + Mod(1, 2)*a^4 + Mod(1, 2)*a^3 + Mod(1, 2)*a^2 + Mod(1, 2)*a + Mod(1, 2)) Their comparison fails as follows: e2._FiniteField_ext_pariElement__value._cmp(e1._FiniteField_ext_pariElement__value ) --- class 'gen.PariError' Traceback (most recent call last) /home/malb/ipython console in module() /home/malb/gen.pyx in gen._pari_trap() class 'gen.PariError': incorrect type (20) I openend a ticket on Trac for this. Martin -- name: Martin Albrecht _pgp: http://pgp.mit.edu:11371/pks/lookup?op=getsearch=0x8EF0DC99 _www: http://www.informatik.uni-bremen.de/~malb _jab: [EMAIL PROTECTED] --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://sage.math.washington.edu/sage/ and http://sage.scipy.org/sage/ -~--~~~~--~~--~--~---
[sage-support] Safari problem with sage notebook
Hi, even though safari is listed as supported the sage notebook doesn't really work properly with it. The arrow keys do not work -- hittin up (or down) at the top (or bottom) of a cell does not take the cursor to the previous (next) cell. Also sometimes it is impossible for a cell to get the focus. For example with the following notebook http://www.sagenb.com/TAexmpl in Safari I can not focus in any cell beyond the 3rd answer. When I click on one of them the cursor moves to the top of the page. -- Nikos --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://sage.math.washington.edu/sage/ and http://sage.scipy.org/sage/ -~--~~~~--~~--~--~---
[sage-support] somewhat secure notebook server
Hi, I would like students in a class to have access to a sage notebook server. My current setup is: I've created the most locked-down user I can in OS X, and from that account (lets call it 'weakuser'), I started up a notebook with a username and password; the notebook files are located at something like /Users/weakuser/NotebookName. I was thinking of giving the username and password for the notebook to my students (these would be different from guest and its password). My question is: is there anything else I can easily do to make this secure? I use the server machine as a desktop a lot, but I back up my work every day. Is this setup reasonably secure? Thanks, Marshall --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://sage.math.washington.edu/sage/ and http://sage.scipy.org/sage/ -~--~~~~--~~--~--~---
[sage-support] Re: somewhat secure notebook server
sagenb.com and sagenb.org are public servers There should be enough security soon that they should be appropriate for your class soon. On 4/3/07, Marshall Hampton [EMAIL PROTECTED] wrote: Hi, I would like students in a class to have access to a sage notebook server. My current setup is: I've created the most locked-down user I can in OS X, and from that account (lets call it 'weakuser'), I started up a notebook with a username and password; the notebook files are located at something like /Users/weakuser/NotebookName. I was thinking of giving the username and password for the notebook to my students (these would be different from guest and its password). My question is: is there anything else I can easily do to make this secure? I use the server machine as a desktop a lot, but I back up my work every day. Is this setup reasonably secure? Thanks, Marshall --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://sage.math.washington.edu/sage/ and http://sage.scipy.org/sage/ -~--~~~~--~~--~--~---
[sage-support] Re: somewhat secure notebook server
On 4/3/07, Timothy Clemans [EMAIL PROTECTED] wrote: sagenb.com and sagenb.org are public servers There should be enough security soon that they should be appropriate for your class soon. No -- these are not appropriate for a class, since they could easily go down for a number of reasons, and they aren't that robust. They are only meant for people to do some temporary testing sharing of SAGE worksheets -- but shouldn't be the main way a person makes SAGE available to a class. On 4/3/07, Marshall Hampton [EMAIL PROTECTED] wrote: I would like students in a class to have access to a sage notebook server. My current setup is: I've created the most locked-down user I can in OS X, and from that account (lets call it 'weakuser'), I started up a notebook with a username and password; the notebook files are located at something like /Users/weakuser/NotebookName. I was thinking of giving the username and password for the notebook to my students (these would be different from guest and its password). My question is: is there anything else I can easily do to make this secure? I use the server machine as a desktop a lot, but I back up my work every day. Is this setup reasonably secure? It is just as secure as giving out a guest login/password to your machine for logging into that account, i.e., it's back to the question of how secure OS X itself is against a local exploit, which is I guess a standard question. In fact, you may want to have a guest account for your students, to allow students with ssh to connect and use the command-line version of SAGE, which some might like. Regarding how you actually start the notebook server, I use this script (with the notebook line having no line break): [EMAIL PROTECTED]:~$ more notebook.py from sage.all import * notebook(port=8101, address=sage.math.washington.edu, jsmath=True, color='gmail', restart_on_crash=True, username=, password=, auto_restart=800) --- Then to actually start the server, I type sage notebook.py Note that auto_restart=800 line, which will completely restart the notebook server every 800 seconds -- this prevents people accidentally (or on purpose) running long-running calculations, which would slow down the machine for your use or other people's use, and helps defend against memory leaks. -- William --~--~-~--~~~---~--~~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://sage.math.washington.edu/sage/ and http://sage.scipy.org/sage/ -~--~~~~--~~--~--~---
