ApCoCoA-1:NC.CToCoCoAL

NC.CToCoCoAL

Convert a polynomial in a non-commutative polynomial ring from the C format to the CoCoAL format.

Syntax

```NC.CToCoCoAL(F:LIST):INT
```

Description

Please set non-commutative polynomial ring (via the command Use) before calling this function. For more information, please check the relevant commands and functions.

• @param F: a non-commutative polynomial in the C format. Every polynomial is represented as a LIST of LISTs, and each inner LIST contains a coefficient and a LIST of indices of indeterminates. For instance, assume that the working ring is QQ[x[1..2],y[1..2]], then indeterminates x[1],x[2],y[1],y[2] are indexed by 1,2,3,4, respectively. Thus the polynomial f=2x[2]y[1]x[2]^2-9y[2]x[1]^2x[2]^3+5 is represented as [[2, [1, 3, 2, 2]], [-9, [4, 1, 1, 2, 2, 2]], [5, []]]. The zero polynomial 0 is represented as the empty LIST [].

• @return: a LIST, which is the CoCoAL format of the polynomial F.

Example

```USE QQ[x[1..2],y[1..2]];
F:= [[2, [1, 3, 2, 2]], [-9, [4, 1, 1, 2, 2, 2]], [5, []]];
NC.CToCoCoAL(F);

[[2x[1], y[1], x[2]^2], [-9y[2], x[1]^2, x[2]^3], [5]]
-------------------------------
```