roland's profile - activity

xsrange vs sxrange? Hi, In version 9.8 Ubuntu, xsrange is faster than sxrange. Why? Roland

Fatal error cython: No such file Hi I am using Ubuntu 22.04 and Sage 9.8. When compiling a Cython function, I got the

TypeError: dist must be a Distribution instance Hi, Suddenly, using Cython magic, I got the message "TypeError: dist m

TypeError: dist must be a Distribution instance Hi, Suddenly, using Cython magic, I got the message "TypeError: dist m

@tmonteil

I got the message: error: command 'gcc' failed with exit status 1

Hi,

One can add extensions to Jupyter, as explained on the jupyter-contrib-nbextensions installation page, for instance with the instruction:

pip install jupyter_contrib_nbextensions

But this instruction does not work using the SageMath 9.0 Shell (in Windows)... Any idea what to do?

Roland

I came across the following example:

  def count(start=0):
      num = start
      while True:
          yield num
          num += 1

When I try to apply it (Sage 8.6), the result is different than I expected:

print [count().next() for i in range(18)]
print next(count())
print next(count())

[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
0
0

Can someone please elucidate why the output is not equal to:

[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17]
0
1

Hi,

Why is there a difference in output between:

 print 5-1 == 0
 print 3^(1/3) - 3^(1/5) == 0

 False
 3^(1/3) - 3^(1/5) == 0

What can I do if $x,y,s,t \in \mathbb Q$, and I want to test $x^y == s^t$?

Thanks for your support!

Roland

I did not expect this behavior... For instance, I would expect an error message or a warning.

Is there an explanation?

Hi,

Please help. The purpose is to export easily a csv file from Sage to Excel (Windows) and via versa. I use VirtualBox. The reason is that Sage is excellent to calculate and Excel is (sometimes) handy to report.

I followed the instructions of 4. Sharing files between Sage and Windows, but I do not understand the last instruction "The files will be in /media/sf_<<volume name="">>".

An example code of reading and writing to a shared map would be great. Thanks!

How can I load a R data file?

I have uploaded Data2.csv. I tried:

  %R
  DataInit<-read.table(DATA+"Data2.csv", header=TRUE, sep=",")

This yields an error:

Traceback (most recent call last):    DataInit<-read.table(DATA+'Data2.csv', header=TRUE, sep=",")
  File "", line 1, in <module>

  File "/home/sage/sage-6.9/local/lib/python2.7/site-packages/sagenb-0.11.4-  py2.7.egg/sagenb/misc/support.py", line 438, in syseval
return system.eval(cmd, sage_globals, locals = sage_globals)
TypeError: unbound method eval() must be called with R instance as first argument (got str instance instead)

Thanks for your kind support!

Jason and John, thanks for your reply. However, I probably was not quite clear regarding my question. You both assumed that I would know cc, but what is the answer to my question if you don't now cc? More general: I have to rows (in QQ), what is the smallest row of integers I can get? It is always possible to generate a row with integers, but the hard part is that I'm looking for the smallest.

Hi, Sage fans. Probably a simple Sage routine does the job, but I tried hard to find it but yet without success…

My problem. Consider two rows (in QQ):

aa=[0,-1,1/5,-1/19,1/15,-35/57,7/5]

bb=[1,0,-6/5,20/19,-7/5,56/19,-12/5]

How to find (x,y) such that [(xaa[i]+ybb[i]) for i in xrange(7)] yields the row [3, -3, -3, 3, -4, 7, -3] with the smallest set integers?

For the above example (x,y)=(3,3) does the job, but is there a general routine to find the optimal (x,y)?

Many thanks in advance for your suggestions! Roland

Based upon the request to be more specific, I would appreciate some guidance on the following two questions: 1) On for instance http://en.wikipedia.org/wiki/Benchmark_(computing) various benchmarks are mentioned. Which are most suitable for me (Sage user) to compare configurations? 2) What improvements can I expect using currently (i) 2 Quad CPU Q6700@2.67Hz 6GB DDR2-800 with Windows 7 and VMWare, versus (ii) Intel Core i7-200k 3,4Gzh 8Mb, 16 G DDR-1333 with 120SSD (Windows+VMWare/Sage 32bit) + 60SSD (Sage 64bit/Ubuntu 11.04)?

Thanks for your explanation. As a non native speaker, it occurred to me that FAQ encourages people to ask questions which address issues of more general interest than addressing a personal issue. I misinterpreted this guidance, and I'm sorry for any inconvenience or irritation caused. N.B.: I'm somewhat puzzled about the difference between ASKSAGE and Sage-Support (general help and support on using Sage, e.g. installation, usage, functions, syntax, etc.)

Hi, technology changes rapidly, and after a few years everyone has to make a choice about new hardware. Now it is my turn...

I could not find many guidance via Google besides some very specific questions and answers on ASKBOT, Sage-support or Sage-devel. Most related are ask.sagemath.org/question/546/good-computer-for-fast-computation and (ask.sagemath.org/question/352/difference-of-performance-bewteen-a-core-i5-and)

What are reasonable standards today? What is nice, but not overdone? What is student level, semi-serious, and top-of-the-bill? What are criteria to buy now, or to wait for say 3-6-9 months? Is the Windows experience tool handy? Many related questions.

Based on the above suggestions: 1) Sage is single core: duo core or 4 core seems also good, isn't it? 2) 16G. Does Windows 7 + VMWARE (32bit) or Ubuntu (64bit) need it? 3) SSD is still. But does it increase speed? Value for money? 4) Are there different requirements for integer MIPS, floating point MIPS, specific applications? 5) Any other considerations, as internet speed?

The same questions, but asked differently. What is nice, but not overdone, for: a) Some integer, floating point or symbolic computations (calculation up to 15 minutes, memory usage < 30Mb)? b) Same as a), but calculations of 8 hours (mainly Cython) and a lot to save?

A third approach is budget related. If your budget is $300,400,500,750,1000,... What are the main issues to consider? (N.B.: Europe is more expensive). Is it just mainly Sage or it is a multipurpose machine. Last: simple PC will do, and heavy stuff possible via sagenb / KAIST (and maybe cloud)? Or should I wait for (multi-core) Cygwin?

Many different questions, but some guidance would be appreciated. For me heavy tasks as gaming, video , photo and music are not relevant. Up till now it seems that Intel Core i7-200k 3,4Gzh 8Mb, 16 G memory with 120SSD+60SSD will do. I can use two OS. But makes it sense? Thanks in advance for your support!

(It may be an idea to have a sage page for it, because it seems to me that it is a general question relevant over time for many).

Hi, I experienced this several times. So I decided to 'save' my work every 10-30 minutes by (i) go to "text", (ii) select and copy all, (iii) store it in a word file. I do not know how to work with Linux, otherwise I would add a routine to do it. Clumsy, but I have certainty. "Save worksheet to file" (*.sws) is a unreliable option especially if the file size exceeds 12Mb. In general, the text files are small in size. The reason this type of 'lifelines' is not added as a standard notebook action is maybe because I noticed over time that almost all developers are not using Windows but only Linux. Roland

Hi,

I FOUND A SOLUTION. My problem was that both config.pickle and user.pickle were empty.

I copied both "standard" files from a earlier version of Sage.

This happens more often; see sage user forum

Maybe the developers could add an exeption handler just like IOError in /notebook.py in __init__(self, dir).

In that case a "basic" copy of both files are read.

Roland

Hi,

I got the following message using Firefox with Sage 4.5.3 via VM 3.1.1 build-282343.

Service Temporarily Unavailable

The server is temporarily unable to service your request due to maintenance downtime or capacity problems. Please try again later. Apache/2.2.12 (Ubuntu) Server at 192.168.231.128 Port 80

Also starting Sage in VM-player (Ubuntu) is strange. It shows only a flash of comments (can't read it) and then the application closes.

I'm especially worried that I cannot reach anymore my workbook files....

Any help is much appreciated!

Roland