9.5.13 `algtodalg', `dalgtoalg', `dptodalg', `dalgtodp'
-------------------------------------------------------

algtodalg(ALG)
     :: $BBe?tE*?t(B ALG $B$r(B `DAlg' $B$KJQ49$9$k(B.

dalgtoalg(DALG)
     :: `DAlg' `dalg' $B$rBe?tE*?t$KJQ49$9$k(B.

dptodalg(DP)
     :: $BJ,;6B?9`<0(B DP $B$r(B `DAlg' $B$KJQ49$9$k(B.

dalgtodp(DALG)
     :: `DAlg' `dalg' $B$rJ,;6B?9`<0$KJQ49$9$k(B.

RETURN
     $BBe?tE*?t(B, `DAlg' $B$^$?$O(B [$BJ,;6B?9`<0(B,$BJ,Jl(B] $B$J$k%j%9%H(B

ALG
     `root' $B$r4^$`Be?tE*?t(B

DP
     $BM-M}?t78?tJ,;6B?9`<0(B

   * `root' $B$r4^$`Be?tE*?t(B, `DAlg' $B$*$h$SJ,;6B?9`<04V$NJQ49$r9T$&(B.

   * `DAlg' $B$,B0$9$Y$-Be?tBN$O(B, `set_field()' $B$K$h$j(B
     $B$"$i$+$8$a@_Dj$7$F$*$/I,MW$,$"$k(B.

   * `dalgtodp()' $B$O(B, $BJ,;R$G$"$k@0?t78?tJ,;6B?9`<0$H(B,
     $BJ,Jl$G$"$k@0?t$rMWAG$K;}$D(B $B%j%9%H$rJV$9(B.

   * `algtodalg()', `dptodalg()' $B$O4JC12=$5$l$?7k2L$rJV$9(B.

     [0] A=newalg(x^2+1);
     (#0)
     [1] B=newalg(x^3+A*x+A);
     (#1)
     [2] set_field([B,A]);
     0
     [3] C=algtodalg((A+B)^10);
     ((408)*<<2,1>>+(103)*<<2,0>>+(-36)*<<1,1>>+(-446)*<<1,0>>
     +(-332)*<<0,1>>+(-218)*<<0,0>>)
     [4] dalgtoalg(C);
     ((408*#0+103)*#1^2+(-36*#0-446)*#1-332*#0-218)
     [5] D=dptodalg(<<10,10>>/10+2*<<5,5>>+1/3*<<0,0>>);
     ((-9)*<<2,1>>+(57)*<<2,0>>+(-63)*<<1,1>>+(-12)*<<1,0>>
     +(-60)*<<0,1>>+(1)*<<0,0>>)/30
     [6] dalgtodp(D);
     [(-9)*<<2,1>>+(57)*<<2,0>>+(-63)*<<1,1>>+(-12)*<<1,0>>
     +(-60)*<<0,1>>+(1)*<<0,0>>,30]

$B;2>H(B
     *Note `set_field': set_field.

