1 | /*****************************************************************************\ |
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2 | * Computer Algebra System SINGULAR |
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3 | \*****************************************************************************/ |
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4 | /** @file facFactorize.h |
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5 | * |
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6 | * multivariate factorization over Q(a) |
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7 | * |
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8 | * @author Martin Lee |
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9 | * |
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10 | * @internal @version \$Id$ |
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11 | * |
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12 | **/ |
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13 | /*****************************************************************************/ |
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14 | |
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15 | #ifndef FAC_FACTORIZE_H |
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16 | #define FAC_FACTORIZE_H |
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17 | |
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18 | #include <config.h> |
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19 | |
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20 | #include "facBivar.h" |
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21 | #include "facFqBivarUtil.h" |
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22 | |
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23 | /// Factorization over Q (a) |
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24 | /// |
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25 | /// @return @a multiFactorize returns a factorization of F |
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26 | CFList |
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27 | multiFactorize (const CanonicalForm& F, ///< [in] poly to be factored |
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28 | const Variable& v ///< [in] some algebraic variable |
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29 | ); |
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30 | |
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31 | /// factorize a squarefree multivariate polynomial over \f$ Q(\alpha) \f$ |
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32 | /// |
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33 | /// @return @a ratSqrfFactorize returns a list of monic factors, the first |
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34 | /// element is the leading coefficient. |
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35 | inline |
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36 | CFList ratSqrfFactorize (const CanonicalForm & F, ///< [in] a multivariate poly |
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37 | const Variable& v |
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38 | ) |
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39 | { |
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40 | if (getNumVars (F) == 2) |
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41 | return ratBiSqrfFactorize (F, v); |
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42 | CFList result= multiFactorize (F, v); |
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43 | if (isOn (SW_RATIONAL)) |
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44 | { |
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45 | normalize (result); |
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46 | result.insert (Lc(F)); |
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47 | } |
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48 | return result; |
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49 | } |
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50 | |
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51 | /// factorize a multivariate polynomial over \f$ Q(\alpha) \f$ |
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52 | /// |
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53 | /// @return @a ratFactorize returns a list of monic factors with |
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54 | /// multiplicity, the first element is the leading coefficient. |
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55 | inline |
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56 | CFFList ratFactorize (const CanonicalForm& F, ///< [in] a multivariate poly |
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57 | const Variable& v |
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58 | ) |
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59 | { |
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60 | if (getNumVars (F) == 2) |
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61 | { |
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62 | CFFList result= ratBiFactorize (F,v); |
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63 | return result; |
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64 | } |
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65 | Variable a= Variable (1); |
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66 | CanonicalForm LcF= Lc (F); |
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67 | |
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68 | CanonicalForm sqrfP= sqrfPart (F); |
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69 | CFList buf; |
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70 | CFFList result; |
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71 | buf= multiFactorize (sqrfP, v); |
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72 | CanonicalForm G= F; |
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73 | result= multiplicity (G, buf); |
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74 | if (isOn (SW_RATIONAL)) |
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75 | { |
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76 | normalize (result); |
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77 | result.insert (CFFactor (LcF, 1)); |
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78 | } |
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79 | return result; |
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80 | } |
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81 | |
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82 | #endif |
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83 | |
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