As advised, I removed the broken installation I obtained via sage -upgrade and
installed sage 3.1.2.

Plotting worked nicely, until roughly 5 minutes ago.  Now I get:
-------------------------------------------------------------------------------
[EMAIL PROTECTED]:~$ sage
----------------------------------------------------------------------
| SAGE Version 3.1.2, Release Date: 2008-09-19                       |
| Type notebook() for the GUI, and license() for information.        |
----------------------------------------------------------------------

sage: plot(sin(x), (x,-1,1))
/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/bin/sage-sage:
line 215: 21171 Illegal instruction     sage-ipython "$@" -c
"$SAGE_STARTUP_COMMAND;"
-------------------------------------------------------------------------------

Note: the only thing I did before was to try SymPy, since I wanted to try out
it's plotting capabilities.  Now, I'm lucky and have the complete history still
on my screen, find it below.

Help would be very much appreciated.

Is it a "no no" to import SymPy?

Martin

----------------------------------------------------------------------
| SAGE Version 3.1.2, Release Date: 2008-09-19                       |
| Type notebook() for the GUI, and license() for information.        |
----------------------------------------------------------------------

max(x,5)sage: max(x,5)
x

Parent: Symbolic Ring
sage: max(pi,e)
pi

Parent: Symbolic Ring
sage: max(x,y)
---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)

/home/martin/<ipython console> in <module>()

NameError: name 'y' is not defined
sage: var('y')
y

Parent: Symbolic Ring
sage: max(x,y)
x

Parent: Symbolic Ring
sage: -4 < 65
True
sage: x < <
------------------------------------------------------------
   File "<ipython console>", line 1
     x < <
         ^
SyntaxError: invalid syntax

sage: x < y
x < y
sage: bool(x < y)
False
sage: bool(y < x)
False
sage: bool(y < x)
bool
sage: bool
bool
sage: te
test.fri             test.fri~            texPatchDiscussion   texput.dvi       
    text.html
test.fri.axh         tests                texPatchDiscussion~  texput.log       
    text3d
test.fri.input       tetrahedron          texput.aux           text             
    text_control
sage: tes
test.fri        test.fri.axh    test.fri.input  test.fri~       tests
sage: test?
Object `test` not found.
sage: tests?
Type:           module
Base Class:     <type 'module'>
String Form:    <module 'sage.tests.all' from 
'/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sage/tests/all.pyc'>
Namespace:      Interactive
File:           
/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sage/tests/all.py
Docstring:
    nodoctest


sage: bool(y < y^2)
False
sage: bool(y < y+1)
True
sage: bool(y < -y)
False
sage: ?bool
Type:           type
Base Class:     <type 'type'>
String Form:    <type 'bool'>
Namespace:      Python builtin
Docstring:
    bool(x) -> bool

    Returns True when the argument x is true, False otherwise.
    The builtins True and False are the only two instances of the class bool.
    The class bool is a subclass of the class int, and cannot be subclassed.

sage: ?<
------------------------------------------------------------
   File "<ipython console>", line 1
     ?<
     ^
SyntaxError: invalid syntax

sage: <?
Object `<` not found.
sage: bool(y < -y)
False
sage: bool(y^2 < (y+1)^2)
False
sage: max(y^2, (y+1)^2)
y^2

Parent: Symbolic Ring
sage: max(0, (y-1)^2)
0

Parent: Integer Ring
sage: max(0, (y+1)^2)
0

Parent: Integer Ring
sage: max(0, y)
0

Parent: Integer Ring
sage: max(y, (y+1)^2)
y

Parent: Symbolic Ring
sage: -y+ (y+1)^2
(y + 1)^2 - y

Parent: Symbolic Ring
sage: expand(-y+ (y+1)^2)
y^2 + y + 1

Parent: Symbolic Ring
sage: expand(-2*y+ (y+1)^2)
y^2 + 1

Parent: Symbolic Ring
sage: max(2*y, (y+1)^2)
2*y

Parent: Symbolic Ring
sage: {max(min(sin(1/x)*exp(-1/x),0.5),-0.5)
....: )
------------------------------------------------------------
   File "<ipython console>", line 2
     )
     ^
SyntaxError: invalid syntax

sage: max(min(sin(1/x)*exp(-1/x),0.5),-0.5))
------------------------------------------------------------
   File "<ipython console>", line 1
     
max(min(sin(Integer(1)/x)*exp(-Integer(1)/x),RealNumber('0.5')),-RealNumber('0.5')))
                                                                                
        ^
SyntaxError: invalid syntax

sage: max(min(sin(1/x)*exp(-1/x),0.5),-0.5)
sin(1/x)*e^(-(1/x))

Parent: Symbolic Ring
sage: min(max(sin(1/x)*exp(-1/x),0.5),-0.5)
sin(1/x)*e^(-(1/x))

Parent: Symbolic Ring
sage: def f = min(max(sin(1/x)*exp(-1/x),0.5),-0.5)
------------------------------------------------------------
   File "<ipython console>", line 1
     def f = 
min(max(sin(Integer(1)/x)*exp(-Integer(1)/x),RealNumber('0.5')),-RealNumber('0.5'))
           ^
SyntaxError: invalid syntax

sage: ?def
Object `def` not found.
sage: def
def
sage: def?
Object `def` not found.
sage: def f: min(max(sin(1/x)*exp(-1/x),0.5),-0.5)
------------------------------------------------------------
   File "<ipython console>", line 1
     def f: 
min(max(sin(Integer(1)/x)*exp(-Integer(1)/x),RealNumber('0.5')),-RealNumber('0.5'))
          ^
SyntaxError: invalid syntax

sage: def f x: min(max(sin(1/x)*exp(-1/x),0.5),-0.5)
------------------------------------------------------------
   File "<ipython console>", line 1
     def f x: 
min(max(sin(Integer(1)/x)*exp(-Integer(1)/x),RealNumber('0.5')),-RealNumber('0.5'))
           ^
SyntaxError: invalid syntax

sage: def f x =  min(max(sin(1/x)*exp(-1/x),0.5),-0.5)
------------------------------------------------------------
   File "<ipython console>", line 1
     def f x =  
min(max(sin(Integer(1)/x)*exp(-Integer(1)/x),RealNumber('0.5')),-RealNumber('0.5'))
           ^
SyntaxError: invalid syntax

sage: def f(x):  min(max(sin(1/x)*exp(-1/x),0.5),-0.5)
....: )
------------------------------------------------------------
   File "<ipython console>", line 2
     )
     ^
SyntaxError: invalid syntax

sage: def f(x):  min(max(sin(1/x)*exp(-1/x),0.5),-0.5))
------------------------------------------------------------
   File "<ipython console>", line 1
     def f(x):  
min(max(sin(Integer(1)/x)*exp(-Integer(1)/x),RealNumber('0.5')),-RealNumber('0.5')))
                                                                                
                   ^
SyntaxError: invalid syntax

sage: def f(x):
....:     min(max(sin(1/x)*exp(-1/x),0.5),-0.5))
------------------------------------------------------------
   File "<ipython console>", line 2
     
min(max(sin(Integer(1)/x)*exp(-Integer(1)/x),RealNumber('0.5')),-RealNumber('0.5')))
                                                                                
        ^
SyntaxError: invalid syntax

sage: def f(x):
....:     x
....:
sage: f(5)
sage: ex =f(5)
sage: ex
sage: def f(x):
....:     return x
....:
sage: f(5)
5

Parent: Integer Ring
sage: f=lambda x: max(min(sin(1/x)*exp(-1/x),0.5),-0.5)
sage: f
<function <lambda> at 0xa15ad84>
sage: f(x)
sin(1/x)*e^(-(1/x))

Parent: Symbolic Ring
sage: f(4)
e^(-1/4)*sin(1/4)

Parent: Symbolic Ring
sage: f(4.0)
0.192678397202388

Parent: Real Field with 53 bits of precision
sage: integrate((x^2+2*x+1+(3*x+1)*sqrt(x+log x))/(x*sqrt(x+log 
x)*(x+sqrt(x+log x))),x)
------------------------------------------------------------
   File "<ipython console>", line 1
     
integrate((x**Integer(2)+Integer(2)*x+Integer(1)+(Integer(3)*x+Integer(1))*sqrt(x+log
 x))/(x*sqrt(x+log x)*(x+sqrt(x+log x))),x)
                                                                                
           ^
SyntaxError: invalid syntax

sage: 
integrate((x^2+2*x+1+(3*x+1)*sqrt(x+log(x)))/(x*sqrt(x+log(x))*(x+sqrt(x+log(x)))),x)
-integrate(((3*x + 1)*log(x)^5 + (-13*x^3 + 9*x^2 + 4*x)*log(x)^4 + (22*x^5 - 
38*x^4 + 10*x^3 + 6*x^2)*log(x)^3 + (-18*x^7 + 50*x^6 - 42*x^5 + 6*x^4 + 
4*x^3)*log(x)^2 + (7*x^9 - 27*x^8 + 38*x^7 - 22*x^6 + 3*x^5 + x^4)*log(x) - 
x^11 + 5*x^10 - 10*x^9 + 10*x^8 - 5*x^7 + x^6)/(5*x^2*log(x)^5 + sqrt(log(x) + 
x)*(25*x^3*log(x)^4 + (100*x^5 + 100*x^4)*log(x)^3 + (110*x^7 + 300*x^6 + 
150*x^5)*log(x)^2 + (20*x^9 + 220*x^8 + 300*x^7 + 100*x^6)*log(x) + x^11 + 
20*x^10 + 110*x^9 + 100*x^8 + 25*x^7) + (60*x^4 + 25*x^3)*log(x)^4 + (126*x^6 + 
240*x^5 + 50*x^4)*log(x)^3 + (60*x^8 + 378*x^7 + 360*x^6 + 50*x^5)*log(x)^2 + 
(5*x^10 + 120*x^9 + 378*x^8 + 240*x^7 + 25*x^6)*log(x) + 5*x^11 + 60*x^10 + 
126*x^9 + 60*x^8 + 5*x^7), x) + integrate(((80*x^2 + 60*x + 20)*log(x) + 32*x^4 
+ 124*x^3 + 80*x^2 + 20*x)/(25*x*log(x)^2 + (50*x^3 + 50*x^2)*log(x) + 5*x^5 + 
50*x^4 + 25*x^3), x) + 3*log(x)/5 - 1/(5*x)

Parent: Symbolic Ring
sage: import sympy
sage: symp
sympow  sympy
sage: sympy.
Display all 358 possibilities? (y or n)
sage: sympy.in
sympy.integrals     sympy.integrate     sympy.intersection  sympy.interval
sage: sympy.integ
sympy.integrals  sympy.integrate
sage: sympy.integrate((x^2+2*x+1+(3*x+1)*sqrt(x+log x))/(x*sqrt(x+log 
x)*(x+sqrt(x+log x))),x)
------------------------------------------------------------
   File "<ipython console>", line 1
     
sympy.integrate((x**Integer(2)+Integer(2)*x+Integer(1)+(Integer(3)*x+Integer(1))*sqrt(x+log
 x))/(x*sqrt(x+log x)*(x+sqrt(x+log x))),x)
                                                                                
                 ^
SyntaxError: invalid syntax

sage: sympy.integrate?
sage: 
sympy.integrate((x^2+2*x+1+(3*x+1)*sqrt(x+log(x)))/(x*sqrt(x+log(x))*(x+sqrt(x+log(x)))),x)
---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)

/home/martin/<ipython console> in <module>()

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sympy/utilities/decorator.py
 in threaded_decorator(expr, *args, **kwargs)
     53                     return Add(*[ func(f, *args, **kwargs) for f in 
expr.args ])
     54                 else:
---> 55                     return func(expr, *args, **kwargs)
     56
     57         threaded_decorator.__doc__  = func.__doc__

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sympy/integrals/integrals.py
 in integrate(*args, **kwargs)
    310
    311     """
--> 312     integral = Integral(*args, **kwargs)
    313
    314     if isinstance(integral, Integral):

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sympy/integrals/integrals.py
 in __new__(cls, function, *symbols, **assumptions)
     40                             continue
     41
---> 42                 raise ValueError("Invalid integration variable or 
limits")
     43         else:
     44             # no symbols provided -- let's compute full antiderivative

ValueError: Invalid integration variable or limits
sage: sympy.var('x')
x
sage: 
sympy.integrate((x^2+2*x+1+(3*x+1)*sqrt(x+log(x)))/(x*sqrt(x+log(x))*(x+sqrt(x+log(x)))),x)
2*log(x + (x + log(x))**(1/2)) + 2*(x + log(x))**(1/2)
sage: sym
symbolic_expression  symmetric            symmetrica           sympow           
    sympy
sage: symp
sympow  sympy
sage: sympy.
Display all 358 possibilities? (y or n)
sage: sympy.g
sympy.gamma     sympy.gcd       sympy.gcdex     sympy.generate  sympy.geometry  
sympy.gosper    sympy.groebner  sympy.gruntz
sage: sympy.gamma?
Type:           FunctionClass
Base Class:     <class 'sympy.core.function.FunctionClass'>
String Form:    gamma
Namespace:      Interactive
File:           
/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sympy/functions/special/gamma_functions.py
Docstring:
    x.__init__(...) initializes x; see x.__class__.__doc__ for signature

sage: sympy.gamma(x)
gamma(x)
sage: diff(sympy.gamma(x),x)
---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)

/home/martin/<ipython console> in <module>()

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sage/calculus/functional.py
 in derivative(f, *args, **kwds)
    131         pass
    132     if not isinstance(f, SymbolicExpression):
--> 133         f = SR(f)
    134     return f.derivative(*args, **kwds)
    135

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sage/calculus/calculus.py
 in __call__(self, x)
    449                 msg, s, pos = err.args
    450                 raise TypeError, "%s: %s !!! %s" % (msg, s[:pos], 
s[pos:])
--> 451         return self._coerce_impl(x)
    452
    453     def _coerce_impl(self, x):

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sage/calculus/calculus.py
 in _coerce_impl(self, x)
    499         from sympy.core.basic import Basic
    500         if isinstance(x, Basic):
--> 501             return self(x._sage_())
    502         else:
    503             raise TypeError, "cannot coerce type '%s' into a 
SymbolicExpression."%type(x)

AttributeError: 'gamma' object has no attribute '_sage_'
sage: (sympy.gamma(x)).diff
<bound method gamma.diff of gamma(x)>
sage: (sympy.gamma(x)).diff()
gamma(x)
sage: (sympy.gamma(x)).diff(x)
gamma(x)*polygamma(0, x)
sage: (sympy.gamma(x)).diff()
gamma(x)
sage: (sympy.gamma(x)).diff?
Object `(sympy.gamma(x)).diff` not found.
sage: sympy.diff?
Type:           function
Base Class:     <type 'function'>
String Form:    <function diff at 0xa2b795c>
Namespace:      Interactive
File:           
/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sympy/core/multidimensional.py
Definition:     sympy.diff(*args, **kwargs)
Docstring:
    Differentiate f with respect to x

        It's just a wrapper to unify .diff() and the Derivative class,
        it's interface is similar to that of integrate()

        see 
http://documents.wolfram.com/v5/Built-inFunctions/AlgebraicComputation/Calculus/D.html


sage: sympy.D
sympy.Derivative  sympy.Dij
sage: sympy.Derivative?
Type:           BasicMeta
Base Class:     <class 'sympy.core.basic.BasicMeta'>
String Form:    <class 'sympy.core.function.Derivative'>
Namespace:      Interactive
File:           
/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sympy/core/function.py
Docstring:

        Carries out differentation of the given expression with respect to 
symbols.

        expr must define ._eval_derivative(symbol) method that returns
        the differentation result or None.

        Examples:

        Derivative(Derivative(expr, x), y) -> Derivative(expr, x, y)
        Derivative(expr, x, 3)  -> Derivative(expr, x, x, x)


sage: sympy.diff()
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)

/home/martin/<ipython console> in <module>()

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sympy/core/multidimensional.py
 in wrapper(*args, **kwargs)
    125                     result = apply_on_element(wrapper, args, kwargs, n)
    126                     return result
--> 127             return f(*args, **kwargs)
    128         wrapper.__doc__ = f.__doc__
    129         wrapper.__name__ = f.__name__

TypeError: diff() takes at least 2 arguments (0 given)
sage: sympy.diff(x)
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)

/home/martin/<ipython console> in <module>()

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sympy/core/multidimensional.py
 in wrapper(*args, **kwargs)
    125                     result = apply_on_element(wrapper, args, kwargs, n)
    126                     return result
--> 127             return f(*args, **kwargs)
    128         wrapper.__doc__ = f.__doc__
    129         wrapper.__name__ = f.__name__

TypeError: diff() takes at least 2 arguments (1 given)
sage: x.diff()
x
sage: x.diff(x)
1
sage: x.diff()
x
sage: x.diff(x,x)
0
sage: (x^3).diff(x,x,x)
6
sage: symp
sympow  sympy
sage: sympy.
Display all 358 possibilities? (y or n)
sage: sympy.m
sympy.make_list                 sympy.min_                      sympy.mr        
                sympy.multinomial
sympy.matrices                  sympy.monomial                  sympy.mr_safe   
                sympy.multinomial_coefficients
sympy.matrix2numpy              sympy.monomial_count            sympy.msolve    
                sympy.multiplicity
sympy.max_                      sympy.monomials                 sympy.mul
sympy.memoization               sympy.mpmath                    
sympy.multidimensional
sage: sympy.ma
sympy.make_list     sympy.matrices      sympy.matrix2numpy  sympy.max_
sage: sympy.max?
Object `sympy.max` not found.
sage: sympy.max_?
Type:           FunctionClass
Base Class:     <class 'sympy.core.function.FunctionClass'>
String Form:    max_
Namespace:      Interactive
File:           
/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sympy/functions/elementary/miscellaneous.py
Docstring:
    x.__init__(...) initializes x; see x.__class__.__doc__ for signature

sage: sympy.max_(x,y)
max_(x, y)
sage: sympy.max_(x,2*x)
max_(x, 2*x)
sage: sympy.p
sympy.partitions_             sympy.poly_groebner           sympy.polynomial    
          sympy.prevprime
sympy.pdfview                 sympy.poly_half_gcdex         sympy.polynomials   
          sympy.prime
sympy.pdiv                    sympy.poly_lcm                sympy.polys         
          sympy.primefactors
sympy.pi                      sympy.poly_pdiv               sympy.polysys       
          sympy.primepi
sympy.plotting                sympy.poly_pquo               sympy.power         
          sympy.primerange
sympy.pngview                 sympy.poly_prem               sympy.powsimp       
          sympy.primetest
sympy.point                   sympy.poly_quo                sympy.pprint        
          sympy.print_gtk
sympy.pollard_pm1             sympy.poly_rem                
sympy.pprint_try_use_unicode  sympy.print_python
sympy.pollard_rho             sympy.poly_resultant          
sympy.pprint_use_unicode      sympy.print_tree
sympy.poly_decompose          sympy.poly_sqf                sympy.pquo          
          sympy.printing
sympy.poly_div                sympy.poly_sturm              sympy.prem          
          sympy.product
sympy.poly_factors            sympy.poly_subresultants      sympy.pretty        
          sympy.products
sympy.poly_gcd                sympy.polygamma               sympy.pretty_print  
          sympy.python
sympy.poly_gcdex              sympy.polygon                 sympy.preview
sage: sympy.plotting
sympy.plotting
sage: sympy.plotting?
Type:           module
Base Class:     <type 'module'>
String Form:    <module 'sympy.plotting' from 
'/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sympy/plotting/__init__.pyc'>
Namespace:      Interactive
File:           
/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sympy/plotting/__init__.py
Docstring:
    Plotting module that can plot 2D and 3D functions


sage: sympy.plotting(x,x,0,1)
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)

/home/martin/<ipython console> in <module>()

TypeError: 'module' object is not callable
sage: sympy.plotting(x,(x,0,1))
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)

/home/martin/<ipython console> in <module>()

TypeError: 'module' object is not callable
sage: sympy.plotting?
Type:           module
Base Class:     <type 'module'>
String Form:    <module 'sympy.plotting' from 
'/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sympy/plotting/__init__.pyc'>
Namespace:      Interactive
File:           
/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sympy/plotting/__init__.py
Docstring:
    Plotting module that can plot 2D and 3D functions


sage: x.plotting
---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)

/home/martin/<ipython console> in <module>()

AttributeError: 'Symbol' object has no attribute 'plotting'
sage: x.plotting()
---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)

/home/martin/<ipython console> in <module>()

AttributeError: 'Symbol' object has no attribute 'plotting'
sage: plotting??
Object `plotting` not found.
sage: sympy.plotting??
Type:           module
Base Class:     <type 'module'>
String Form:    <module 'sympy.plotting' from 
'/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sympy/plotting/__init__.pyc'>
Namespace:      Interactive
File:           
/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sympy/plotting/__init__.py
Source:
"""Plotting module that can plot 2D and 3D functions
"""
try:
    try:
        from ctypes import *
    except:
        raise ImportError("ctypes is required for plotting.\n'easy_install 
ctypes' or visit http://sourceforge.net/projects/ctypes/";)

    def Plot(*args, **kwargs):
        import plot
        return plot.Plot(*args, **kwargs)

except Exception, e:
    def Plot(*args, **kwargs):
        raise e

from textplot import textplot
sage: sympy.P
sympy.Plot                sympy.Poly                sympy.PolynomialError     
sympy.PrecisionExhausted
sympy.Point               sympy.Polygon             sympy.Pow                 
sympy.Product
sage: sympy.Plot?
Type:           function
Base Class:     <type 'function'>
String Form:    <function Plot at 0xa4068ec>
Namespace:      Interactive
File:           
/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sympy/plotting/__init__.py
Definition:     sympy.Plot(*args, **kwargs)
Docstring:
    x.__init__(...) initializes x; see x.__class__.__doc__ for signature

sage: x
x
sage: parent(x)
<class 'sympy.core.symbol.Symbol'>
sage: plot(x,(x,0,1))
---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)

/home/martin/<ipython console> in <module>()

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sage/plot/plot.py
 in plot(funcs, *args, **kwds)
   3570         # if there is one extra arg, then it had better be a tuple
   3571         elif n == 1:
-> 3572             G = _plot(funcs, *args, **kwds)
   3573         elif n == 2:
   3574         # if there are two extra args, then pull them out and pass them 
as a tuple

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sage/plot/plot.py
 in _plot(funcs, xrange, parametric, polar, label, randomize, **kwds)
   3596
   3597     if not is_fast_float(funcs):
-> 3598         funcs =  fast_float(funcs)
   3599
   3600     #parametric_plot will be a list or tuple of two functions (f,g)

/home/martin/fast_eval.pyx in sage.ext.fast_eval.fast_float 
(sage/ext/fast_eval.c:7031)()

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sympy/core/basic.py
 in __float__(self)
   1863             return float(result)
   1864         else:
-> 1865             raise ValueError("Symbolic value, can't compute")
   1866
   1867     def __complex__(self):

ValueError: Symbolic value, can't compute
sage: plot(x,(0,1))
---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)

/home/martin/<ipython console> in <module>()

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sage/plot/plot.py
 in plot(funcs, *args, **kwds)
   3570         # if there is one extra arg, then it had better be a tuple
   3571         elif n == 1:
-> 3572             G = _plot(funcs, *args, **kwds)
   3573         elif n == 2:
   3574         # if there are two extra args, then pull them out and pass them 
as a tuple

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sage/plot/plot.py
 in _plot(funcs, xrange, parametric, polar, label, randomize, **kwds)
   3596
   3597     if not is_fast_float(funcs):
-> 3598         funcs =  fast_float(funcs)
   3599
   3600     #parametric_plot will be a list or tuple of two functions (f,g)

/home/martin/fast_eval.pyx in sage.ext.fast_eval.fast_float 
(sage/ext/fast_eval.c:7031)()

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sympy/core/basic.py
 in __float__(self)
   1863             return float(result)
   1864         else:
-> 1865             raise ValueError("Symbolic value, can't compute")
   1866
   1867     def __complex__(self):

ValueError: Symbolic value, can't compute
sage: x.plot((0,1))
---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)

/home/martin/<ipython console> in <module>()

AttributeError: 'Symbol' object has no attribute 'plot'
sage: x.Plot((0,1))
---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)

/home/martin/<ipython console> in <module>()

AttributeError: 'Symbol' object has no attribute 'Plot'
sage: x.Plot((x,0,1))
---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)

/home/martin/<ipython console> in <module>()

AttributeError: 'Symbol' object has no attribute 'Plot'
sage: Plot(x)
---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)

/home/martin/<ipython console> in <module>()

NameError: name 'Plot' is not defined
sage: from sym
symbol    symtable
sage: from Sy
symbol    symtable  sys       syslog
sage: from sym
symbol    symtable
sage: from sympy import *
sage: Plot(
Display all 2146 possibilities? (y or n)
sage: Plot(x)
[0]: x, 'mode=cartesian'
sage: Plot?
Type:           function
Base Class:     <type 'function'>
String Form:    <function Plot at 0xa4068ec>
Namespace:      Interactive
File:           
/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sympy/plotting/__init__.py
Definition:     Plot(*args, **kwargs)
Docstring:
    x.__init__(...) initializes x; see x.__class__.__doc__ for signature

sage: Plot??
Type:           function
Base Class:     <type 'function'>
String Form:    <function Plot at 0xa4068ec>
Namespace:      Interactive
File:           
/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sympy/plotting/__init__.py
Definition:     Plot(*args, **kwargs)
Source:
    def Plot(*args, **kwargs):
        import plot
        return plot.Plot(*args, **kwargs)
sage: ?Plot
Type:           function
Base Class:     <type 'function'>
String Form:    <function Plot at 0xa4068ec>
Namespace:      Interactive
File:           
/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sympy/plotting/__init__.py
Definition:     Plot(*args, **kwargs)
Docstring:
    x.__init__(...) initializes x; see x.__class__.__doc__ for signature

sage: plot(x)
---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)

/home/martin/<ipython console> in <module>()

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sage/plot/plot.py
 in plot(funcs, *args, **kwds)
   3567         # if there are no extra args, pick some silly default
   3568         if n == 0:
-> 3569             G = _plot(funcs, (-1, 1), *args, **kwds)
   3570         # if there is one extra arg, then it had better be a tuple
   3571         elif n == 1:

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sage/plot/plot.py
 in _plot(funcs, xrange, parametric, polar, label, randomize, **kwds)
   3596
   3597     if not is_fast_float(funcs):
-> 3598         funcs =  fast_float(funcs)
   3599
   3600     #parametric_plot will be a list or tuple of two functions (f,g)

/home/martin/fast_eval.pyx in sage.ext.fast_eval.fast_float 
(sage/ext/fast_eval.c:7031)()

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sympy/core/basic.py
 in __float__(self)
   1863             return float(result)
   1864         else:
-> 1865             raise ValueError("Symbolic value, can't compute")
   1866
   1867     def __complex__(self):

ValueError: Symbolic value, can't compute
sage: Plot(x,(-1,1))
[0]: x, 'mode=cartesian'
sage: Plot(sin(1/x),(-1,1))
[0]: sin(1/x), 'mode=cartesian'
sage: Plot(sin(1/x),(-2,2))
[0]: sin(1/x), 'mode=cartesian'
sage: plot(sin(1/x),(-2,2))
---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)

/home/martin/<ipython console> in <module>()

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sage/plot/plot.py
 in plot(funcs, *args, **kwds)
   3570         # if there is one extra arg, then it had better be a tuple
   3571         elif n == 1:
-> 3572             G = _plot(funcs, *args, **kwds)
   3573         elif n == 2:
   3574         # if there are two extra args, then pull them out and pass them 
as a tuple

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sage/plot/plot.py
 in _plot(funcs, xrange, parametric, polar, label, randomize, **kwds)
   3596
   3597     if not is_fast_float(funcs):
-> 3598         funcs =  fast_float(funcs)
   3599
   3600     #parametric_plot will be a list or tuple of two functions (f,g)

/home/martin/fast_eval.pyx in sage.ext.fast_eval.fast_float 
(sage/ext/fast_eval.c:7031)()

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sympy/core/basic.py
 in __float__(self)
   1863             return float(result)
   1864         else:
-> 1865             raise ValueError("Symbolic value, can't compute")
   1866
   1867     def __complex__(self):

ValueError: Symbolic value, can't compute
sage: plot(sin(1/y),(y,-2,2))
---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)

/home/martin/<ipython console> in <module>()

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sage/plot/plot.py
 in plot(funcs, *args, **kwds)
   3570         # if there is one extra arg, then it had better be a tuple
   3571         elif n == 1:
-> 3572             G = _plot(funcs, *args, **kwds)
   3573         elif n == 2:
   3574         # if there are two extra args, then pull them out and pass them 
as a tuple

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sage/plot/plot.py
 in _plot(funcs, xrange, parametric, polar, label, randomize, **kwds)
   3596
   3597     if not is_fast_float(funcs):
-> 3598         funcs =  fast_float(funcs)
   3599
   3600     #parametric_plot will be a list or tuple of two functions (f,g)

/home/martin/fast_eval.pyx in sage.ext.fast_eval.fast_float 
(sage/ext/fast_eval.c:7031)()

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sympy/core/basic.py
 in __float__(self)
   1863             return float(result)
   1864         else:
-> 1865             raise ValueError("Symbolic value, can't compute")
   1866
   1867     def __complex__(self):

ValueError: Symbolic value, can't compute
sage: y
y

Parent: Symbolic Ring
sage: plot(sin(1/y),(y,-2,2))
---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)

/home/martin/<ipython console> in <module>()

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sage/plot/plot.py
 in plot(funcs, *args, **kwds)
   3570         # if there is one extra arg, then it had better be a tuple
   3571         elif n == 1:
-> 3572             G = _plot(funcs, *args, **kwds)
   3573         elif n == 2:
   3574         # if there are two extra args, then pull them out and pass them 
as a tuple

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sage/plot/plot.py
 in _plot(funcs, xrange, parametric, polar, label, randomize, **kwds)
   3596
   3597     if not is_fast_float(funcs):
-> 3598         funcs =  fast_float(funcs)
   3599
   3600     #parametric_plot will be a list or tuple of two functions (f,g)

/home/martin/fast_eval.pyx in sage.ext.fast_eval.fast_float 
(sage/ext/fast_eval.c:7031)()

/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/lib/python2.5/site-packages/sympy/core/basic.py
 in __float__(self)
   1863             return float(result)
   1864         else:
-> 1865             raise ValueError("Symbolic value, can't compute")
   1866
   1867     def __complex__(self):

ValueError: Symbolic value, can't compute
sage: plot(lambda y: sin(1/y),(y,-2,2))
/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/bin/sage-sage: 
line 215: 18608 Illegal instruction     sage-ipython "$@" -c 
"$SAGE_STARTUP_COMMAND;"
[EMAIL PROTECTED]:~$ sage
----------------------------------------------------------------------
| SAGE Version 3.1.2, Release Date: 2008-09-19                       |
| Type notebook() for the GUI, and license() for information.        |
----------------------------------------------------------------------

sage: plot(sin(1/x),(x,-1,1))
/home/martin/sage-3.1.2-ubuntu32bit-i686-intel-i686-Linux/local/bin/sage-sage: 
line 215: 21052 Illegal instruction     sage-ipython "$@" -c 
"$SAGE_STARTUP_COMMAND;"


--~--~---------~--~----~------------~-------~--~----~
To post to this group, send email to sage-support@googlegroups.com
To unsubscribe from this group, send email to [EMAIL PROTECTED]
For more options, visit this group at 
http://groups.google.com/group/sage-support
URLs: http://www.sagemath.org
-~----------~----~----~----~------~----~------~--~---

Reply via email to