substitute(ChainComplex,Ring) -- Substitute a chain complex to a new ring.

i1 : R=QQ[x_1..x_8];

i2 : Z=QQ[z];

i3 : cc=cycResDef(4,R,Z);

i4 : S= ring cc;

i5 : cc

      1      16      30      16      1
o5 = S  <-- S   <-- S   <-- S   <-- S
                                     
     0      1       2       3       4

o5 : ChainComplex

i6 : print cc.dd_1
| x_1x_3x_5 x_1x_3x_6 x_1x_4x_6 x_2x_4x_6 x_2x_4x_7 x_2x_5x_7 x_3x_5x_7 x_8zx_3-x_1x_3x_7 x_8zx_4-x_1x_4x_7 x_8x_2x_4 x_8zx_5-x_1x_5x_7 x_8x_2x_5 x_8x_3x_5 x_8x_2x_6 x_8x_3x_6 x_8x_4x_6 |

i7 : cs=substitute(cc,R)

      1      16      30      16      1
o7 = R  <-- R   <-- R   <-- R   <-- R
                                     
     0      1       2       3       4

o7 : ChainComplex

i8 : print cs.dd_1
| x_1x_3x_5 x_1x_3x_6 x_1x_4x_6 x_2x_4x_6 x_2x_4x_7 x_2x_5x_7 x_3x_5x_7 -x_1x_3x_7 -x_1x_4x_7 x_2x_4x_8 -x_1x_5x_7 x_2x_5x_8 x_3x_5x_8 x_2x_6x_8 x_3x_6x_8 x_4x_6x_8 |