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#121 bogus <code>property change</code> comments ←	↑	→ #123 Compile modified spad file

#122 Handling of power series

Edit detail for #122 Handling of power series revision 2 of 3

	1 2 3
Editor: kratt6 Time: 2009/04/19 06:54:05 GMT-7
Note: fixed in FriCAS revision 583

added:

From kratt6 Sun Apr 19 06:54:05 -0700 2009
From: kratt6
Date: Sun, 19 Apr 2009 06:54:05 -0700
Subject: fixed in FriCAS revision 583
Message-ID: <20090419065405-0700@axiom-wiki.newsynthesis.org>

Status: open => fixed somewhere

It seems that the interpreter handles strangely the power series:

fricas

a:= series sin(x)

$\label{eq1}\begin{array}{@{}l} \displaystyle x -{{1 \over 6}\ {{x}^{3}}}+{{1 \over{120}}\ {{x}^{5}}}-{{1 \over{5 040}}\ {{x}^{7}}}+{{1 \over{362880}}\ {{x}^{9}}}-{{1 \over{39 916800}}\ {{x}^{11}}}+ \ \ \displaystyle {O \left({{x}^{12}}\right)}$

(1)

Type: UnivariatePuiseuxSeries?(Expression(Integer),x,0)

fricas

)di type a

   Type of value of a: Any
-- If I coerce it...
a:=a::UnivariatePuiseuxSeries(Expression Float,x,0)

$\label{eq2}\begin{array}{@{}l} \displaystyle x -{{0.1666666666_6666666667}\ {{x}^{3}}}+ \ \ \displaystyle {{0.0083333333_3333333333_34}\ {{x}^{5}}}- \ \ \displaystyle {{0.0001984126_9841269841_27}\ {{x}^{7}}}+ \ \ \displaystyle {{0.0000027557_3192239858_90653}\ {{x}^{9}}}- \ \ \displaystyle {{0.2505210838_5441718775 E - 7}\ {{x}^{11}}}+{O \left({{x}^{1 2}}\right)}$

(2)

Type: UnivariatePuiseuxSeries?(Expression(Float),x,0.0)

fricas

)di type a

   Type of value of a: UnivariatePuiseuxSeries(Expression(Float),x,0.0)
a*1.0

$\label{eq3}\begin{array}{@{}l} \displaystyle x -{{0.1666666666_6666666667}\ {{x}^{3}}}+ \ \ \displaystyle {{0.0083333333_3333333333_34}\ {{x}^{5}}}- \ \ \displaystyle {{0.0001984126_9841269841_27}\ {{x}^{7}}}+ \ \ \displaystyle {{0.0000027557_3192239858_90653}\ {{x}^{9}}}- \ \ \displaystyle {{0.2505210838_5441718775 E - 7}\ {{x}^{11}}}+{O \left({{x}^{1 2}}\right)}$

(3)

Type: UnivariatePuiseuxSeries?(Expression(Float),x,0.0)

Fatal bug:

 a:= series sin(x);
 a*1.0;
 >> System error:
 Caught fatal error [memory may be damaged]
 protected-symbol-warn called with (NIL)

From trace it seems that the interpreter doesn't coerce one args in Expression (Float):

  1<enter valueArgsEqual? : (|UnivariatePuiseuxSeries| (|Expression| (|Integer|)) |x| 
               ((0 . 0) 0 . 1))\
               (|UnivariatePuiseuxSeries| (|Expression| (|Float|)) |x| ((0 . 0) 0 . 1))
  ...

And here:

 1<enter algEqual : ((0 . 0) 0 . 1)\((0 0 . 0) 0 1 . 0)\(|Expression| (|Float|))
 1<enter compiledLookupCheck : =\((|Boolean|) $ !$)\#<vector 08eccc78>
 1>exit compiledLookupCheck : (#<compiled-function |EXPR;=;2$B;21|> . #<vector 08eccc78>)

after SPADCALL (it's not traced) "=" in EXPR trigger the bug:

  algEqual : ((0 . 0) 0 . 1)\((0 0 . 0) 0 1 . 0)\(|Expression| (|Float|))
             ^^^^^^^^^^^^^^^

I think above is not of type EXPR FLOAT.

Other thing:

fricas

1.0::UnivariatePuiseuxSeries(Expression Float,x,0.0)

$\label{eq4}1.0$

(4)

Type: UnivariatePuiseuxSeries?(Expression(Float),x,0.0)

Memory damaged if it's added to .axiom.input

Edit detail for #122 Handling of power series revision 2 of 3

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