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2015-03-26 22:12:33 -0600 marked best answer cannot run: from sage.rings.number_field.splitting_field import SplittingData

When I type this line

from sage.rings.number_field.splitting_field import SplittingData

in Sage, I get the following error message:

Traceback (click to the left of this block for traceback)
...
ImportError: No module named splitting_field

I see in the online documentation that splitting fields of polynomials over number fields is very recent in Sage:

2014-01-02 Jeroen Demeyer
2015-03-26 22:12:33 -0600 marked best answer how to plot poset and subposet in a graph?

hot to put poset and subposet and order_filter and order_ideal in one graph,but different color?

PP = Posets(6)[18];show(PP,vertex_size=100,vertex_colors='yellow');

Q = PP.subposet([2,4]);Q;show(Q,vertex_size=100,vertex_colors='green')

PP.order_filter([3,2]);PP.order_ideal([4,3])

2015-03-26 22:12:32 -0600 marked best answer why sagenb.mc.edu cannot register?

sage.lacim.uqam.ca cannot register too ,why?

and sage.lacim.uqam.ca not in wiki.sagemath.org servers lists,why?

2015-03-26 22:12:28 -0600 marked best answer is notebook(interface='', secure=False) a loophole?

I try command:notebook(),it is some information about SAGENB servers......

I have no more secrity knowledge about computer,It maybe change admin passwords?

2015-03-26 22:12:25 -0600 marked best answer question about hilbert_class_polynomial

I run sagecell hilbert_class_polynomial sqrt(-5),but different with below:

http://echidna.maths.usyd.edu.au/kohe...

http://sagenb.skku.edu/home/pub/155/

2015-03-26 22:10:25 -0600 marked best answer AttributeError: 'NumberFieldFractionalIdeal' object has no attribute 'ray_class_number'

ray_class_number canot run.....

I tried an example from doc/reference:

K.<z> = QuadraticField(-23);
p = K.primes_above(3)[0];
p.ray_class_number()

x = polygen(K)
L.<w> = K.extension(x^3 - z)
I = L.ideal(5)
I.ray_class_number()
2015-03-26 22:10:01 -0600 marked best answer when I unloading a *.sws,how cannot find it out ?

I download SM_sphere_S2.sws,and uploading it (project/new/to Upload files from your computer),but where is it? no save button..... link text

2015-03-26 22:09:58 -0600 marked best answer what matrix.plot meanings?

when I run bolow,a graph appears,how to understand it?

matrix([[3,-1,1],[2,0,1],[1,-1,2]]).plot()

2015-03-26 22:09:58 -0600 marked best answer some links cannot back Sage Reference Manual

1 https://sage.epsevg.upc.edu:8000/doc/...

when link below,no button to back to Sage Reference Manual

REFERENCES:

[WpJacobianVariety] http://en.wikipedia.org/wiki/Jacobian...

2

https://sage.epsevg.upc.edu:8000/doc/...

when link below,no button to back to Sage Reference Manual,it link to http://trac.sagemath.org/13100,but blank page...

there are more links like above troubles at other places in Sage Reference Manual,I meet several times

2015-03-26 22:09:57 -0600 marked best answer where is all others published in cloud sage?

where is all others published in cloud sage?

I try cloud.sage can plot and published myself, it very well

but where others published?

the cloud projects use like labyrinth, it is too complex.......

2015-03-26 22:09:57 -0600 marked best answer how to transfer *.svg to *.gif or jepg?

how to transfer *.svg to *.gif or jepg?

2015-03-26 22:09:57 -0600 marked best answer how to define var vector?
sage: a,b,c=var("a,b,c")
sage: v = vector(QQ, ["a", "b", "c"]);v
...
TypeError: unable to convert a to a rational

cannot run

2015-03-26 22:09:56 -0600 marked best answer how to use the function ord()?

ord? there no example.

and other function like lambda?, no in index of Sage Reference Manual

2015-03-26 22:09:56 -0600 marked best answer why lim((x^2-x+1)^(1/2)+x,x=-oo,dir='below') is red error

x=-oo, negative infinity,the answei is appear,but red error,1/2 is right?

lim((x^2-x+1)^(1/2)+x,x=-oo,dir='below')

Error in lines 0-2
Traceback (most recent call last):
  File "/projects/9e8c4ed8-0b57-4535-b8f1-a0d0ef1b015b/.sagemathcloud/sage_server.py", line 841, in execute
    exec compile(block+'\n', '', 'single') in namespace, locals
  File "<string>", line 1
    )
    ^
SyntaxError: invalid syntax
2015-03-26 22:09:56 -0600 marked best answer what meanings about global_height of AffineSpace'point

P.<x,y>=AffineSpace(QQ,2) Q=P(41,1/12) Q.global_height()

2015-03-26 22:09:19 -0600 marked best answer can sagecloud open many windows like sagenb?

sagenb has many windiws when need,how to do in sagecloud?

2015-03-26 22:09:11 -0600 marked best answer sagecell version is 6.0?

sagecell version is 6.0?

2015-03-26 22:09:10 -0600 marked best answer what meanings about "xmrange_iter([[0, 1], [0, 1]], <function <lambda> at 0xb94ab1c>)"
K.<a> = NumberField(x^2 +26);K;I = K.ideal(2);show(I)
res =  I.residues(); res;show(list(res));res =  (2*I).residues(); res;show(list(res))



***xmrange_iter([[0, 1], [0, 1]], <function <lambda> at
0xb94ab1c>)***
[0,a,1,a+1]

***xmrange_iter([[-1, 0, 1, 2], [-1, 0, 1, 2]], <function <lambda>
at 0xb94abfc>)***
[?a?1,?1,a?1,2a?1,?a,0,a,2a,?a+1,1,a+1,2a+1,?a+2,2,a+2,2a+2]



I know [0, 1] is a coordinates but what meanings about "lambda","0xb94abfc"?
2015-03-26 22:09:01 -0600 marked best answer what is katsura ideal in Documentation

http://sagemath.org/doc/reference/rin...

I search katsura here,but no define about katsura ideal.

http://www.math.keio.ac.jp/~katsura/p...

2015-03-26 22:08:55 -0600 marked best answer how to get a ideal of Power Series Ring
K.<u> = PowerSeriesRing(GF(5,4)); K
I = K.ideal(u^2+3,u^12), I

When I run the above in sagecell, nothing appears.

How to get the ideal is_commutative or prime or max_ideal or principal?

2015-03-26 22:08:50 -0600 marked best answer numerical approximations of complex_embedding

How can I get a numerical approximation of an expression like 3^(1/2)/2 which is not 0.866025403784439?

2015-03-26 22:08:50 -0600 marked best answer the same function appears twice in the documentation

The functions base_field()/constant_base_field()/constant_field()/vector_space()/maximal_order()/random_element appear twice in the following document:

http://sagemath.org/doc/reference/fun...

and what different with RationalFunctionField() and FunctionField()?

2015-03-26 22:08:50 -0600 marked best answer how to get the general formula of SHA-TATE GROUP?

how to get SHA general formula by parametrization a1, a2, a3, a4, a6,no a number

E=EllipticCurve([0,1]);E;S=E.sha();S

Elliptic Curve defined by y^2 = x^3 + 1 over Rational Field
Tate-Shafarevich group for the Elliptic Curve defined by y^2 = x^3 + 1
over Rational Field

 R.<a1,a2,a3,a4,a6>=QQ[];show(R);E=EllipticCurve([a1,a2,a3,a4,a6]);show(E)

Multivariate Polynomial Ring in a1, a2, a3, a4, a6 over Rational Field
Elliptic Curve defined by y^2 + a1*x*y + a3*y = x^3 + a2*x^2 + a4*x + a6
over Multivariate Polynomial Ring in a1, a2, a3, a4, a6 over Rational
Field

S=E.sha();S

Traceback (click to the left of this block for traceback)
...
AttributeError: 'EllipticCurve_generic_with_category' object has no
attribute 'sha'
2015-03-26 22:08:49 -0600 marked best answer when home/pub can recover?

http://wiki.sagemath.org/reu/2011/sch...

http://nt.sagenb.org/home/pub/72/ http://nt.sagenb.org/home/pub/79/ http://nt.sagenb.org/home/pub/139/

and there are many code about home/pub at http://sagemath.org/library-publicati....

if sagenb willnot support from 5.12 to 6.12,old home/pub will add to sagecloud in the future?

2015-03-26 22:08:49 -0600 marked best answer how to get two modules tensor_prduct()
u = vector(QQ, [1/2, 1/3, 1/4, 1/5])
v = vector(ZZ, [60, 180, 600])
u.outer_product(v),v.outer_product(u),u.tensor_product(v),v.tensor_product(u)

(
[ 30  90 300]                     [ 30  90 300]                   
[ 20  60 200]  [ 30  20  15  12]  [ 20  60 200]  [ 30  20  15  12]
[ 15  45 150]  [ 90  60  45  36]  [ 15  45 150]  [ 90  60  45  36]
[ 12  36 120], [300 200 150 120], [ 12  36 120], [300 200 150 120]
)

above are two vectors'tensor_product,but when use two mudules,cannot run....

M=FreeModule(ZZ,3);M
N=FreeModule(ZZ,7);N
M.outer_product(N),M.tensor_product(N)

AttributeError                            Traceback (most recent call last)
<ipython-input-1-ad4483c60043> in <module>()
      1 M=FreeModule(ZZ,Integer(3));M
      2 N=FreeModule(ZZ,Integer(7));N
----> 3 M.outer_product(N),M.tensor_product(N)

/home/sageserver/sage/local/lib/python2.7/site-packages/sage/structure/parent.so in sage.structure.parent.Parent.__getattr__ (build/cythonized/sage/structure/parent.c:7367)()

/home/sageserver/sage/local/lib/python2.7/site-packages/sage/structure/misc.so in sage.structure.misc.getattr_from_other_class (build/cythonized/sage/structure/misc.c:1687)()

AttributeError: 'FreeModule_ambient_pid_with_category' object has no attribute 'outer_product'
2015-03-26 22:08:48 -0600 marked best answer can sagecell show more than one line codes results?

below three lines codes can get three results in sagenb,but in sagecell only can show the third line codes result.....

K.<u> = CyclotomicField(28);K;
Ga=K.galois_group(names='y');Ga;
table(Ga.list(),frame=True).transpose()
2015-03-26 22:08:48 -0600 marked best answer ValueError: too many values to unpack

I want try prime ideal factorzation in extension field,how to run [i.L.is_galois() for i, _ in SUB]

http://sagenb.skku.edu/home/pub/143/

2015-03-26 22:08:42 -0600 marked best answer <repr(<sage.modular.modform.element.Newform at 0x7f0c8fa15c30>) failed: IndexError: list index out of range>],
M11=ModularForms(11,2,base_ring=Qp(7,10));show(M11.modular_symbols()),show(M11),M11.level(),M11.weight(),M11.character(),M11.dimension(),M11.group().order(),M11.group().gens(),M11.newforms(),M11.free_module(),show(M11.hecke_module_of_level(1)),

1 why \QQ7 is red?maybe 7-adic field Op7?

2 free_module is error.

<repr(<sage.modular.modform.element.newform at="" 0x7f0c8fa15c30="">) failed: IndexError: list index out of range>],

2015-03-26 22:08:40 -0600 marked best answer when sagecell run show(),the result only above top
var('k a b c d');q=solve(k*x^4+a*x^3+b*x^2+c*x+d==0,x);q,show(q[0].simplify_full()),show(q[1].simplify_full()),show(q[2].simplify_full()),show(q[3].simplify_full())

show(q[3].simplify_full()) is the last command,but the result appear the toppest