$sage -sh Starting subshell with Sage environment variables set. Don't forget to exit when you are done. Beware: * Do not do anything with other copies of Sage on your system. * Do not use this for installing Sage packages using "sage -i" or for running "make" at Sage's root directory. These should be done outside the Sage shell.
Bypassing shell configuration files... Note: SAGE_ROOT=/home/shhu/Documents/SageMath (sage-sh) shhu@shhu-ee-tau:Program$ theta Usage: theta <graph> ----------------------------------------------------------------- I have 'csdp' installed, and this theta function works for many other graphs. However, it doesn't work for this graph... 在 2016年5月10日星期二 UTC+3下午7:45:24，Dima Pasechnik写道： > > and on other graphs either? > (e.g. on graphs.CycleGraph(7)) > > Start sage prompt (sage -sh) and check that you have the program called > theta available: > $ sage -sh > > Starting subshell with Sage environment variables set. Don't forget > to exit when you are done. Beware: > * Do not do anything with other copies of Sage on your system. > * Do not use this for installing Sage packages using "sage -i" or for > running "make" at Sage's root directory. These should be done > outside the Sage shell. > > Bypassing shell configuration files... > > Note: SAGE_ROOT=/home/dima/software/sage > (sage-sh) dima@dimpase:~$ theta > Usage: > > theta <graph> > (sage-sh) dima@dimpase:~$ > > ------------- > if you don't have it then reinstall csdp: > sage -f csdp > > > > On Tuesday, May 10, 2016 at 5:14:09 PM UTC+1, Sihuang Hu wrote: >> >> It didn't work for me. :( >> >> sage: g=Graph([[0,1],[2,3]]) >> sage: g.lovasz_theta() >> >> --------------------------------------------------------------------------- >> ValueError Traceback (most recent call >> last) >> <ipython-input-2-1d4d0397a94f> in <module>() >> ----> 1 g.lovasz_theta() >> >> /home/shhu/Documents/SageMath/local/lib/python2.7/site-packages/sage/graphs/lovasz_theta.pyc >> >> in lovasz_theta(graph) >> 78 tf.close() >> 79 lines = subprocess.check_output([os.path.join(SAGE_LOCAL, >> 'bin', 'theta'), tf_name]) >> ---> 80 return float(lines.split()[-1]) >> >> ValueError: could not convert string to float: failed. >> >> >> 在 2016年5月10日星期二 UTC+3下午6:33:50，Dima Pasechnik写道： >>> >>> all this works for me just fine: >>> >>> sage: g=Graph([[0,1],[2,3]]) >>> sage: g.lovasz_theta() >>> 2.0 >>> sage: G = graphs.CycleGraph(7) >>> sage: V = Set(G.vertices()) >>> sage: L = [] >>> sage: for s in V.subsets(): >>> ....: L.append(G.subgraph(s)) >>> ....: >>> sage: L[68].lovasz_theta() >>> 2.0 >>> >>> Can you try the following: >>> sage: g=Graph([[0,1],[2,3]]) >>> sage: g.lovasz_theta() >>> >>> >>> >>> On Tuesday, May 10, 2016 at 2:32:04 PM UTC+1, Sihuang Hu wrote: >>>> >>>> The adjacency matrix of the graph is >>>> >>>> [0 1 0 0] >>>> [1 0 0 0] >>>> [0 0 0 1] >>>> [0 0 1 0] >>>> >>>> >>>> 在 2016年5月10日星期二 UTC+3下午4:30:06，Dima Pasechnik写道： >>>>> >>>>> What is your L[68] ? >>>>> This is probably something like a graph without edges... >>>>> >>>>> On Tuesday, May 10, 2016 at 1:53:17 PM UTC+1, Sihuang Hu wrote: >>>>>> >>>>>> Thanks for the comments. >>>>>> I have installed package 'csdp' before. I got this error after I >>>>>> installed it. >>>>>> >>>>>> 在 2016年5月10日星期二 UTC+3下午3:32:59，vdelecroix写道： >>>>>>> >>>>>>> The error you get is quite strange. On my computer with sage-7.1 I >>>>>>> got >>>>>>> >>>>>>> sage: graphs.CycleGraph(7).lovasz_theta() >>>>>>> Traceback (most recent call last): ur ... >>>>>>> PackageNotFoundError: the package 'csdp' was not found. You can >>>>>>> install >>>>>>> it by running 'sage -i csdp' in a shell >>>>>>> >>>>>>> Which is very explicit about what to do... could you install the >>>>>>> csdp >>>>>>> package and try again? >>>>>>> >>>>>>> On 10/05/16 06:58, Sihuang Hu wrote: >>>>>>> > Hi guys, >>>>>>> > >>>>>>> > When I try to compute the lovasz theta number of some graph, it >>>>>>> says that >>>>>>> > >>>>>>> > *ValueError: could not convert string to float: failed.:*G = >>>>>>> > graphs.CycleGraph(7) >>>>>>> > V = Set(G.vertices()) >>>>>>> > L = [] >>>>>>> > for s in V.subsets(): >>>>>>> > L.append(G.subgraph(s)) >>>>>>> > >>>>>>> > L[68].lovasz_theta() >>>>>>> > >>>>>>> --------------------------------------------------------------------------- >>>>>>> >>>>>>> > ValueError Traceback (most recent >>>>>>> call last) >>>>>>> > <ipython-input-53-0ad2fb49c2b1> in <module>() >>>>>>> > ----> 1 L[Integer(68)].lovasz_theta() >>>>>>> > >>>>>>> > >>>>>>> /home/shhu/Documents/SageMath/local/lib/python2.7/site-packages/sage/graphs/lovasz_theta.pyc >>>>>>> >>>>>>> >>>>>>> > in lovasz_theta(graph) >>>>>>> > 78 tf.close() >>>>>>> > 79 lines = >>>>>>> subprocess.check_output([os.path.join(SAGE_LOCAL, >>>>>>> > 'bin', 'theta'), tf_name]) >>>>>>> > ---> 80 return float(lines.split()[-1]) >>>>>>> > >>>>>>> > ValueError: could not convert string to float: failed. >>>>>>> > >>>>>>> > Thanks in advance! >>>>>>> > >>>>>>> >>>>>> -- You received this message because you are subscribed to the Google Groups "sage-support" group. 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