[sage-support] problem with matrix over finite field
This works on sage-8.5:
sage: a = var('a')
: matrix(GF(25, a), [[1,0], [0, 1]])
:
[1 0]
[0 1]
but not on sage-8.6 or later:
sage: a = var('a')
: matrix(GF(25, a), [[1,0], [0, 1]])
:
p025.zzz: No such file or directory
---
RuntimeError Traceback (most recent call last)
in ()
1 a = var('a')
> 2 matrix(GF(Integer(25), a), [[Integer(1),Integer(0)], [Integer(0),
Integer(1)]])
/ext/sage/sage-8.8_1804/local/lib/python2.7/site-packages/sage/matrix/constructor.pyx
in sage.matrix.constructor.matrix
(build/cythonized/sage/matrix/constructor.c:2417)()
623 :class:`MatrixArgs`, see :trac:`24742`
624 """
--> 625 return MatrixArgs(*args, **kwds).matrix()
626
627
/ext/sage/sage-8.8_1804/local/lib/python2.7/site-packages/sage/matrix/args.pyx
in sage.matrix.args.MatrixArgs.matrix
(build/cythonized/sage/matrix/args.c:7765)()
656 break
657 else:
--> 658 M = self.space(self, coerce=convert)
659
660 # Also store the matrix to support multiple calls of
matrix()
/ext/sage/sage-8.8_1804/local/lib/python2.7/site-packages/sage/matrix/matrix_space.pyc
in __call__(self, entries, coerce, copy)
815 [t]
816 """
--> 817 return self.element_class(self, entries, copy, coerce)
818
819 def change_ring(self, R):
/ext/sage/sage-8.8_1804/local/lib/python2.7/site-packages/sage/matrix/matrix_gfpn_dense.pyx
in sage.matrix.matrix_gfpn_dense.Matrix_gfpn_dense.__init__
(build/cythonized/sage/matrix/matrix_gfpn_dense.c:5245)()
427 cdef long nc = ma.ncols
428
--> 429 self.Data = MatAlloc(fl, nr, nc)
430 self._converter = FieldConverter(ma.base)
431
RuntimeError: Cannot select field GF(25) in file matcore.c (line 130)
This is on Ubuntu 18.04, on CoCalc.
--
You received this message because you are subscribed to the Google Groups
"sage-support" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to sage-support+unsubscr...@googlegroups.com.
To post to this group, send email to sage-support@googlegroups.com.
Visit this group at https://groups.google.com/group/sage-support.
To view this discussion on the web visit
https://groups.google.com/d/msgid/sage-support/edfa5067-b473-4242-8879-1a35a93cca33%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.
[sage-support] Re: Numerical integration and parametic curves
Appreciate the pointers.
Plot statement in prior posting could also be
parametric_plot((g,h),(-pi,pi))
which has a nicer default aspect ratio.
BTW there is sage code for Cornu spiral in the wikipedia article, Euler
spiral http://en.wikipedia.org/wiki/Euler_spiral.
On Wednesday, September 10, 2014 4:56:05 AM UTC-5, Volker Braun wrote:
The s = var('s') is not necessary (the argument s inside the functions
shadows it).
As for the original question, IMHO there is a learning opportunity here.
Numerical integration is powerful, but it doesn't give you symbolic
answers. Even if you make the integration bound a symbolic variable.
On Wednesday, September 10, 2014 6:09:06 AM UTC+1, Hal Snyder wrote:
This works on my sage-6.1.1:
s = var('s')
def g(s):
return numerical_integral(cos(pi*x^2/2), 0, s, max_points=100)[0]
def h(s):
return numerical_integral(sin(pi*x^2/2), 0, s, max_points=100)[0]
p = plot((g,h),(-pi,pi),parametric=True)
show(p)
On Tuesday, September 9, 2014 5:17:14 PM UTC-5, Jotace wrote:
Hi all,
I want (my students) to plot Cornu's spiral, givent in parametric form
by
x(t) = integral cos(pi/u^2/2), u going from 0 to t , and y(t) defined
analogously using the sine function. The integral connot be evaluated
symbolically, I guess.
The first attempt would be
parametric_plot([integrate(cos(pi*u^2/2),u,0,t),integrate(sin(pi*u^2/2),u,0,t)],(t,-pi,pi))
which failw (coercion)
The second attempt would be:
parametric_plot([integral_numerical(cos(pi*u^2/2),0,t),integral_numerical(sin(pi*u^2/2),0,t)],(t,-pi,pi))
which also fails.
I finally did:
def x(t):
return integral_numerical(cos(pi*u^2/2),0,t)[0]
def y(t):
return integral_numerical(sin(pi*u^2/2),0,t)[0]
Points = [(x(t),y(t)) for t in sxrange(-pi,pi,2*pi/200)]
line(Points).show(figsize=[5, 5],aspect_ratio=1)
This works, but it looks highly inelegant. Also, i cannot expect my
students to come up with something like this in a first year undergrad
course.
Is there a way to fix one of the first two options?
Regards,
JC
--
You received this message because you are subscribed to the Google Groups
sage-support group.
To unsubscribe from this group and stop receiving emails from it, send an email
to sage-support+unsubscr...@googlegroups.com.
To post to this group, send email to sage-support@googlegroups.com.
Visit this group at http://groups.google.com/group/sage-support.
For more options, visit https://groups.google.com/d/optout.
[sage-support] Re: Numerical integration and parametic curves
This works on my sage-6.1.1:
s = var('s')
def g(s):
return numerical_integral(cos(pi*x^2/2), 0, s, max_points=100)[0]
def h(s):
return numerical_integral(sin(pi*x^2/2), 0, s, max_points=100)[0]
p = plot((g,h),(-pi,pi),parametric=True)
show(p)
On Tuesday, September 9, 2014 5:17:14 PM UTC-5, Jotace wrote:
Hi all,
I want (my students) to plot Cornu's spiral, givent in parametric form by
x(t) = integral cos(pi/u^2/2), u going from 0 to t , and y(t) defined
analogously using the sine function. The integral connot be evaluated
symbolically, I guess.
The first attempt would be
parametric_plot([integrate(cos(pi*u^2/2),u,0,t),integrate(sin(pi*u^2/2),u,0,t)],(t,-pi,pi))
which failw (coercion)
The second attempt would be:
parametric_plot([integral_numerical(cos(pi*u^2/2),0,t),integral_numerical(sin(pi*u^2/2),0,t)],(t,-pi,pi))
which also fails.
I finally did:
def x(t):
return integral_numerical(cos(pi*u^2/2),0,t)[0]
def y(t):
return integral_numerical(sin(pi*u^2/2),0,t)[0]
Points = [(x(t),y(t)) for t in sxrange(-pi,pi,2*pi/200)]
line(Points).show(figsize=[5, 5],aspect_ratio=1)
This works, but it looks highly inelegant. Also, i cannot expect my
students to come up with something like this in a first year undergrad
course.
Is there a way to fix one of the first two options?
Regards,
JC
--
You received this message because you are subscribed to the Google Groups
sage-support group.
To unsubscribe from this group and stop receiving emails from it, send an email
to sage-support+unsubscr...@googlegroups.com.
To post to this group, send email to sage-support@googlegroups.com.
Visit this group at http://groups.google.com/group/sage-support.
For more options, visit https://groups.google.com/d/optout.
[sage-support] Quick Search missing/broken for OSX 10.9.4?
I'm adding info to a problem previously reported on this group - https://groups.google.com/d/msg/sage-support/W02WUZjnX9I/1pr4MiVHpLEJ - if I launch notebook() from the Sage binary, browse to help and then to any of the top row of links (Tutorial, Reference Manual, etc.), the left navbar has the text for Quick Search, but there is no input field. If I view source for the localhost page, the form definition form class=search action=search.html method=get.../form that shows up in the online version at www.sagemath.org/doc/reference is absent. - if I launch tutorial() or manual() directly from the sage prompt, the search text field appears in the left navbar, but when I enter text in it, I am taken to a screen that says preparing search. There is a sequence of dots that animate, but the search does not complete. I don't see any processes consuming appreciable CPU time. I've reproduced this on two Macs running OS X 10.9.4, with versions of sage built from 6.3 through 6.4 beta2 source, as well as from the pre-built binary at boxen: sage-6.3-x86_64-Darwin-OSX_10.9_x86_64.dmg, and with Chrome, Safari, and Firefox. I wonder if others are seeing this, or if there is some obvious config setting I can check. -- You received this message because you are subscribed to the Google Groups sage-support group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-support+unsubscr...@googlegroups.com. To post to this group, send email to sage-support@googlegroups.com. Visit this group at http://groups.google.com/group/sage-support. For more options, visit https://groups.google.com/d/optout.
[sage-support] exponents with units of measurement?
Is there a way to simplify sqrt(some_unit_of_measurement^2) without knowing what's in the expression? Often a chain of computations will lead to a result like the following: 7.5 * sqrt(units.length.meter^2) I would sage to simplify the units and give me 7.50*meter but haven't found symbolic expression ops to get past this output: 7.50*sqrt(meter^2) -- You received this message because you are subscribed to the Google Groups sage-support group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-support+unsubscr...@googlegroups.com. To post to this group, send email to sage-support@googlegroups.com. Visit this group at http://groups.google.com/group/sage-support. For more options, visit https://groups.google.com/d/optout.
Re: [sage-support] exponents with units of measurement?
how could I have missed that? Thank you! On Monday, September 1, 2014 10:35:11 PM UTC-5, shersonb wrote: Try the .simplify_radical() method. ~Brian -- You received this message because you are subscribed to the Google Groups sage-support group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-support+unsubscr...@googlegroups.com. To post to this group, send email to sage-support@googlegroups.com. Visit this group at http://groups.google.com/group/sage-support. For more options, visit https://groups.google.com/d/optout.
[sage-support] Re: My Reference Manualdoesnt have a Quick search input box.
Reproduced here with Sage Version 6.3, Release Date: 2014-08-10 on OS X 10.9.4 and Google Chrome. 1. No search box at bottom of left navbar in reference manual if I follow link from notebook() and help, or visit the help link directly in the notebook server at http://localhost:8080/doc/live/reference/index.html. 2. But search box is there if I do manual() from the sage command prompt and view in the same browser, which is using file URL: file:///Users/.../ sage/src/doc/output/html/en/reference/index.html On Sunday, August 10, 2014 7:47:31 AM UTC-5, Emmanuel Charpentier wrote: Hmmm... Turns out it's not that simple : From the *NOTEBOOK*, when you click on help, you get a new browser window displaying http://localhost:8080/help, which as a Reference manual button leading you to http://localhost:8080/doc/live/reference/index.html, which has, in bottom of the left panel the mention quick search in large character, and the mention Enter search terms or a module, class or function name. in normal characters, but no input box for searching. From the *COMMAND LINE*, the manual() function directly opens a new browser window opening file:///usr/local/sage-6.3/src/doc/output/html/en/reference/index.html, which has the same mentions as from notebook AND an input box and a Go bytton between title and explanatory text. Calling sage from emacs with sage_mode gives the same behaviour. So it *seems* that the notebook, which passes its requests to the sage server, gets a Web page somewhat different from the raw file the browser gets from the files of the local documentation. I hope it's clear, but it's difficult to describe. HTH, -- Emmanuel Charpentier Le dimanche 10 août 2014 13:38:58 UTC+2, Volker Braun a écrit : The reference manual (http://www.sagemath.org/doc/reference/index.html http://www.google.com/url?q=http%3A%2F%2Fwww.sagemath.org%2Fdoc%2Freference%2Findex.htmlsa=Dsntz=1usg=AFQjCNFI6s6W9Th6tx9BQ_dcDf0rMsiLfg) does have the search box even in recent versions for me. It doesn't have interactive cells. What are you looking at exactly? On Sunday, August 10, 2014 10:07:51 AM UTC+1, Emmanuel Charpentier wrote: I just noticed that in the recent versions of Sage (6.3betaSomething), the reference manual I get after compilation does not have an input box for quick search in the left panel. I checked that this was not a browser problem : I have no proble accessing the online manual's http://www.sagemath.org/doc/reference/ quick search box. I also checked that (my) manual *is* interactive (I can modify celle contents and get relevant results). So I probably missed something in the compilation configuration. The question is, of course, What ?. Sincerely, -- Emmanuel Charpentier -- You received this message because you are subscribed to the Google Groups sage-support group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-support+unsubscr...@googlegroups.com. To post to this group, send email to sage-support@googlegroups.com. Visit this group at http://groups.google.com/group/sage-support. For more options, visit https://groups.google.com/d/optout.
[sage-support] Re: numerical approximation with units of measurement?
Thank you! I have a lot to learn about Sage, I can see. Will study
experiment with recn.
In most cases, an integer exponent should look like 2 and not
2.000, don't you think? So I guess I would not n() the exponents.
I have just started using Sage and SMC with some online classes. It's great
to:
- check work with units of measure
- take notes that look like math rather than COBOL (+1 typeset_mode)
- do symbolic and numerical calculations in those same typeset notes
I'm hooked. :-)
On Friday, June 6, 2014 6:53:18 PM UTC-5, Nils Bruin wrote:
On Thursday, June 5, 2014 6:32:42 PM UTC-7, Hal Snyder wrote:
IIs there a simple way to take n() of things without getting into the
following?
You could automate the application, but you'll quickly see you need to be
a bit careful:
#unfortunately, the operators returned for sums and products of multiple
#arguments are callable, but don't accept multiple arguments, so we need to
#do a little surgery ourselves (borrow the functionality from elsewhere):
opdict = {
operator.mul : sage.interfaces.maxima_lib.mul_vararg,
operator.add : sage.interfaces.maxima_lib.add_vararg,
}
def recn(e):
try:
return n(e)
except TypeError:
pass
op=e.operator()
if op:
if op in opdict:
op = opdict[op]
return op(*[recn(c) for c in e.operands()])
else:
return e
--
This now works, a little bit:
sage: recn(area)
21.5161409036487*meter^2.00
As you can see, the exponent in meter^2 was also numerified. Perhaps you
didn't want that?
Nonetheless, a recursive n(..) method seems eminently reasonable and
desirable to implement.
--
You received this message because you are subscribed to the Google Groups
sage-support group.
To unsubscribe from this group and stop receiving emails from it, send an email
to sage-support+unsubscr...@googlegroups.com.
To post to this group, send email to sage-support@googlegroups.com.
Visit this group at http://groups.google.com/group/sage-support.
For more options, visit https://groups.google.com/d/optout.
[sage-support] numerical approximation with units of measurement?
Is there a preferred way of taking numerical approximation of a quantity in Sage with units of measure? Here is a contrived example: r = 123/47 * units.length.meter r area = pi * r^2 area output: 123/47*meter 15129/2209*pi*meter^2 Now imagine that r is not a literal but the result of other calculations involving units of measure, so you can't easily apply n() at the time of assignment to r. Is there a simple way to take n() of things without getting into the following? # n(r) n(r.coeffs()[0][0]^r.coeffs()[0][1])*r.args()[0] == 2.61702127659574*meter # n(area) (n(area.coeffs()[0][0])*(area.args()[0])^area.coeffs()[0][1]) == 21.5161409036487*meter^2 ### -- You received this message because you are subscribed to the Google Groups sage-support group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-support+unsubscr...@googlegroups.com. To post to this group, send email to sage-support@googlegroups.com. Visit this group at http://groups.google.com/group/sage-support. For more options, visit https://groups.google.com/d/optout.
