Pedro's profile - activity

Meanwhile there is no solution:

>>> exec(preparse(r"""
... a = 2^3
... print a
... """))
8
>>> a
8
>>> exit
> py$a
8

or also:

>>> load("some.sage")

• Example of what is needed in sage prompt:

  sage: is_sageprompt()

  True

• Example of what is needed in a notebook:

In an input cell: is_sagenotebook()

The output cell: True

In a notebook cell one can write:

%latex

Hello

\ [

x=f(x)

\ ]

and an image appear with perfect math notation. (not jsmath)

What is the sage command that does the same receiving a string ? Something like latexrender(r"Hello \ [x=f(x)\ ]")

How can we develop the function below ? Where should we start to read?

"""
HSLOG = "High School Log".

Treat forms like `\log_b(a^p)` in a special manner.

Standard sage log with integer arguments works like this:

::     
    sage: log(101^3,10)
    log(1030301)/log(10)
    sage: 3*log(101,10)
    3*log(101,10)
    sage: 10^log(101,base=10)  #101
    10^(log(101)/log(10))

and     

::    
    sage: log(101,10)
    log(101)/log(10)
    sage: latex( log(101,10) )
    \frac{\log\left(101\right)}{\log\left(10\right)}  %ie: log(101)/log(10)

What we want is:

    sage: HSLOG(101,10,3)   #log_{10}(101^3)
    3*log(101,10)
    sage: HSLOG(101,10) #log_{10}(101)
    log(101,10)
    sage: 10^HSLOG(101,10) #10^log_{10}(101^3) = 101
    101
    sage: latex( HSLOG(101,10) )
    \log_{10}(101)


"""

How to determine the maximum element of a matrix? For "matrix_integer_dense" there is height() [1]. For numpy matrix there is max function. How to do it in Sage matrices with one single "max" like instruction ?

[1] http://www.sagemath.org/doc/reference...

[2] Alternetive: m.numpy().max()

The habit of the search for standards made ask the question. Thank you.

Is there any package that produces a JSON string from sage dictionary containing "basic" sage types ?

Something like [1]:

class jsonmegua(json.JSONEncoder):

def default(self, o):
    try:
        if type(o)==sage.rings.integer.Integer:
            json_obj = int(o)
        elif type(o)==sage.rings.real_mpfr.RealLiteral:
            json_obj = float(o)
        elif type(o)==sage.rings.real_mpfr.RealNumber:
            json_obj = float(o)
        elif type(o)==sage.symbolic.expression.Expression:
            json_obj = latex(o)
        else:
            json_obj = o
    except TypeError:
        pass
    else:
        return json_obj

    # Let the base class default method raise the TypeError
    return JSONEncoder.default(self, o)

[1] http://docs.python.org/2/library/json...

After a plot has been made, how can one change options but not using show() or save()?

Does command "change_options" in this code exists ?

   p = plot(some plot)
   p.change_options(ticks=[None, 1.5/4])

later on

 
p.show()

By "later" I mean few days later and not just the next computation. Maybe this is not an effective mathematical question because random is random at all times (stopping or not). Starting from a seed there's a cycle in generated random number. But maybe that's no important to follow the same cycle if I interrupt the computation. Thanks.

I've read but probably I'm missing the answer.

How to start using random() and stop the process and then recover the random generation from the point where it stopped?

Example

  set_random_seed(0)
  some cycle calling random()

later

  set_random_seed( ...where??... )
  more steps of some cycle calling random()

There is an env variable of sorts called EMBEDDED_MODE, I think, which is used internally to tell whether one is in the notebook.

----------------------------------------------------------------------
| Sage Version 4.6.2.alpha1, Release Date: 2011-01-20                |
| Type notebook() for the GUI, and license() for information.        |
----------------------------------------------------------------------
**********************************************************************
*                                                                    *
* Warning: this is a prerelease version, and it may be unstable.     *
*                                                                    *
**********************************************************************
Loading Sage library. Current Mercurial branch is: plotpatches
sage: sage.plot.plot.EMBEDDED_MODE
False

But in the notebook this will give True.

Sage Notebook is now a different product from Sage Mathematics. I would like to reference only to SageNB. I will use nb.sagemath.org as a reference. Thanks.

Is there any list of published texts about SageNB? Thanks.

Thanks. 'file' is new to me and a nice tool. A long term idea is to pre-build worksheets, a different one for each user to upload each.

(I remember reading about it but could find again.)