Primer Gaussove eliminacije z enoliˇ cno reˇsitvijo
Fakulteta za raˇcunalniˇstvo in informatiko Univerza v Ljubljani
Gaussova eliminacija: enoliˇ cna reˇsitev
pivot: spravlja poddiagonalce na 0 poddiagonalni element ˇze urejeno obmoˇcje: ne spreminjamo veˇc zgornjetrikotna oblika
1 2 0 0 3
1 3 0 1 4
−2 −6 1 −1 −7
2 4 2 3 8
II −I III+ 2I IV −2I
1 2 0 0 3
0 1 0 1 1
0 −2 1 −1 −1
0 0 2 3 2
III + 2II
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 2 3 2
IV −2III
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 0 1 0
IV 1w = 0 =⇒ w = 0;
III z+w = 1 =⇒ z = 1 II y+w = 1 =⇒ y = 1 I x+ 2y = 3 =⇒ x = 1
Gaussova eliminacija: enoliˇ cna reˇsitev
pivot: spravlja poddiagonalce na 0 poddiagonalni element ˇze urejeno obmoˇcje: ne spreminjamo veˇc zgornjetrikotna oblika
1 2 0 0 3
1 3 0 1 4
−2 −6 1 −1 −7
2 4 2 3 8
II −I III+ 2I IV −2I
1 2 0 0 3
0 1 0 1 1
0 −2 1 −1 −1
0 0 2 3 2
III + 2II
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 2 3 2
IV −2III
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 0 1 0
IV 1w = 0 =⇒ w = 0;
III z+w = 1 =⇒ z = 1 II y+w = 1 =⇒ y = 1 I x+ 2y = 3 =⇒ x = 1
Gaussova eliminacija: enoliˇ cna reˇsitev
pivot: spravlja poddiagonalce na 0 poddiagonalni element ˇze urejeno obmoˇcje: ne spreminjamo veˇc zgornjetrikotna oblika
1 2 0 0 3
1 3 0 1 4
−2 −6 1 −1 −7
2 4 2 3 8
II −I III+ 2I IV −2I
1 2 0 0 3
0 1 0 1 1
0 −2 1 −1 −1
0 0 2 3 2
III + 2II
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 2 3 2
IV −2III
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 0 1 0
IV 1w = 0 =⇒ w = 0;
III z+w = 1 =⇒ z = 1 II y+w = 1 =⇒ y = 1 I x+ 2y = 3 =⇒ x = 1
Gaussova eliminacija: enoliˇ cna reˇsitev
pivot: spravlja poddiagonalce na 0 poddiagonalni element ˇze urejeno obmoˇcje: ne spreminjamo veˇc zgornjetrikotna oblika
1 2 0 0 3
1 3 0 1 4
−2 −6 1 −1 −7
2 4 2 3 8
II −I III+ 2I IV −2I
1 2 0 0 3
0 1 0 1 1
0 −2 1 −1 −1
0 0 2 3 2
III + 2II
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 2 3 2
IV −2III
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 0 1 0
IV 1w = 0 =⇒ w = 0;
III z+w = 1 =⇒ z = 1 II y+w = 1 =⇒ y = 1 I x+ 2y = 3 =⇒ x = 1
Gaussova eliminacija: enoliˇ cna reˇsitev
pivot: spravlja poddiagonalce na 0 poddiagonalni element ˇze urejeno obmoˇcje: ne spreminjamo veˇc zgornjetrikotna oblika
1 2 0 0 3
1 3 0 1 4
−2 −6 1 −1 −7
2 4 2 3 8
II −I III+ 2I IV −2I
1 2 0 0 3
0 1 0 1 1
0 −2 1 −1 −1
0 0 2 3 2
III + 2II
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 2 3 2
IV −2III
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 0 1 0
IV 1w = 0 =⇒ w = 0;
III z+w = 1 =⇒ z = 1 II y+w = 1 =⇒ y = 1 I x+ 2y = 3 =⇒ x = 1
Gaussova eliminacija: enoliˇ cna reˇsitev
pivot: spravlja poddiagonalce na 0 poddiagonalni element ˇze urejeno obmoˇcje: ne spreminjamo veˇc zgornjetrikotna oblika
1 2 0 0 3
1 3 0 1 4
−2 −6 1 −1 −7
2 4 2 3 8
II −I III+ 2I IV −2I
1 2 0 0 3
0 1 0 1 1
0 −2 1 −1 −1
0 0 2 3 2
III + 2II
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 2 3 2
IV −2III
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 0 1 0
IV 1w = 0 =⇒ w = 0;
III z+w = 1 =⇒ z = 1 II y+w = 1 =⇒ y = 1 I x+ 2y = 3 =⇒ x = 1
Gaussova eliminacija: enoliˇ cna reˇsitev
pivot: spravlja poddiagonalce na 0 poddiagonalni element ˇze urejeno obmoˇcje: ne spreminjamo veˇc zgornjetrikotna oblika
1 2 0 0 3
1 3 0 1 4
−2 −6 1 −1 −7
2 4 2 3 8
II −I III+ 2I IV −2I
1 2 0 0 3
0 1 0 1 1
0 −2 1 −1 −1
0 0 2 3 2
III + 2II
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 2 3 2
IV −2III
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 0 1 0
IV 1w = 0 =⇒ w = 0;
III z+w = 1 =⇒ z = 1 II y+w = 1 =⇒ y = 1 I x+ 2y = 3 =⇒ x = 1
Gaussova eliminacija: enoliˇ cna reˇsitev
pivot: spravlja poddiagonalce na 0 poddiagonalni element ˇze urejeno obmoˇcje: ne spreminjamo veˇc zgornjetrikotna oblika
1 2 0 0 3
1 3 0 1 4
−2 −6 1 −1 −7
2 4 2 3 8
II −I III+ 2I IV −2I
1 2 0 0 3
0 1 0 1 1
0 −2 1 −1 −1
0 0 2 3 2
III + 2II
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 2 3 2
IV −2III
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 0 1 0
IV 1w = 0 =⇒ w = 0;
III z+w = 1 =⇒ z = 1 II y+w = 1 =⇒ y = 1 I x+ 2y = 3 =⇒ x = 1
Gaussova eliminacija: enoliˇ cna reˇsitev
pivot: spravlja poddiagonalce na 0 poddiagonalni element ˇze urejeno obmoˇcje: ne spreminjamo veˇc zgornjetrikotna oblika
1 2 0 0 3
1 3 0 1 4
−2 −6 1 −1 −7
2 4 2 3 8
II −I III+ 2I IV −2I
1 2 0 0 3
0 1 0 1 1
0 −2 1 −1 −1
0 0 2 3 2
III + 2II
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 2 3 2
IV −2III
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 0 1 0
IV 1w = 0 =⇒ w = 0;
III z+w = 1 =⇒ z = 1 II y+w = 1 =⇒ y = 1 I x+ 2y = 3 =⇒ x = 1
Gaussova eliminacija: enoliˇ cna reˇsitev
pivot: spravlja poddiagonalce na 0 poddiagonalni element ˇze urejeno obmoˇcje: ne spreminjamo veˇc zgornjetrikotna oblika
1 2 0 0 3
1 3 0 1 4
−2 −6 1 −1 −7
2 4 2 3 8
II −I III+ 2I IV −2I
1 2 0 0 3
0 1 0 1 1
0 −2 1 −1 −1
0 0 2 3 2
III + 2II
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 2 3 2
IV −2III
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 0 1 0
IV 1w = 0 =⇒ w = 0;
III z+w = 1 =⇒ z = 1 II y+w = 1 =⇒ y= 1 I x+ 2y = 3 =⇒ x= 1
Gaussova eliminacija: enoliˇ cna reˇsitev
pivot: spravlja poddiagonalce na 0 poddiagonalni element ˇze urejeno obmoˇcje: ne spreminjamo veˇc zgornjetrikotna oblika
1 2 0 0 3
1 3 0 1 4
−2 −6 1 −1 −7
2 4 2 3 8
II −I III+ 2I IV −2I
1 2 0 0 3
0 1 0 1 1
0 −2 1 −1 −1
0 0 2 3 2
III + 2II
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 2 3 2
IV −2III
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 0 1 0
IV 1w = 0 =⇒ w = 0;
III z+w = 1 =⇒ z = 1
II y+w = 1 =⇒ y= 1 I x+ 2y = 3 =⇒ x= 1
Gaussova eliminacija: enoliˇ cna reˇsitev
pivot: spravlja poddiagonalce na 0 poddiagonalni element ˇze urejeno obmoˇcje: ne spreminjamo veˇc zgornjetrikotna oblika
1 2 0 0 3
1 3 0 1 4
−2 −6 1 −1 −7
2 4 2 3 8
II −I III+ 2I IV −2I
1 2 0 0 3
0 1 0 1 1
0 −2 1 −1 −1
0 0 2 3 2
III + 2II
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 2 3 2
IV −2III
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 0 1 0
IV 1w = 0 =⇒ w = 0;
III z+w = 1 =⇒ z = 1 II y+w = 1 =⇒ y= 1
I x+ 2y = 3 =⇒ x= 1
Gaussova eliminacija: enoliˇ cna reˇsitev
pivot: spravlja poddiagonalce na 0 poddiagonalni element ˇze urejeno obmoˇcje: ne spreminjamo veˇc zgornjetrikotna oblika
1 2 0 0 3
1 3 0 1 4
−2 −6 1 −1 −7
2 4 2 3 8
II −I III+ 2I IV −2I
1 2 0 0 3
0 1 0 1 1
0 −2 1 −1 −1
0 0 2 3 2
III + 2II
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 2 3 2
IV −2III
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 0 1 0
IV 1w = 0 =⇒ w = 0;
III z+w = 1 =⇒ z = 1 II y+w = 1 =⇒ y= 1 I x+ 2y = 3 =⇒ x= 1
Gaussova-Jordanova eliminacija: alternativa vstavljanju
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 0 1 0
II−IV III −IV
1 2 0 0 3 0 1 0 0 1 0 0 1 0 1 0 0 0 1 0
I −2II
1 0 0 0 1 0 1 0 0 1 0 0 1 0 1 0 0 0 1 0
I x= 1 II y = 1 III z = 1 IV w = 0
Gaussova-Jordanova eliminacija: alternativa vstavljanju
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 0 1 0
II−IV III −IV
1 2 0 0 3 0 1 0 0 1 0 0 1 0 1 0 0 0 1 0
I −2II
1 0 0 0 1 0 1 0 0 1 0 0 1 0 1 0 0 0 1 0
I x= 1 II y = 1 III z = 1 IV w = 0
Gaussova-Jordanova eliminacija: alternativa vstavljanju
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 0 1 0
II−IV III −IV
1 2 0 0 3 0 1 0 0 1 0 0 1 0 1 0 0 0 1 0
I −2II
1 0 0 0 1 0 1 0 0 1 0 0 1 0 1 0 0 0 1 0
I x= 1 II y = 1 III z = 1 IV w = 0
Gaussova-Jordanova eliminacija: alternativa vstavljanju
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 0 1 0
II−IV III −IV
1 2 0 0 3 0 1 0 0 1 0 0 1 0 1 0 0 0 1 0
I −2II
1 0 0 0 1 0 1 0 0 1 0 0 1 0 1 0 0 0 1 0
I x= 1 II y = 1 III z = 1 IV w = 0
Gaussova-Jordanova eliminacija: alternativa vstavljanju
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 0 1 0
II−IV III −IV
1 2 0 0 3 0 1 0 0 1 0 0 1 0 1 0 0 0 1 0
I −2II
1 0 0 0 1 0 1 0 0 1 0 0 1 0 1 0 0 0 1 0
I x= 1 II y = 1 III z = 1 IV w = 0
Gaussova-Jordanova eliminacija: alternativa vstavljanju
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 0 1 0
II−IV III −IV
1 2 0 0 3 0 1 0 0 1 0 0 1 0 1 0 0 0 1 0
I −2II
1 0 0 0 1 0 1 0 0 1 0 0 1 0 1 0 0 0 1 0
I x= 1 II y = 1 III z = 1 IV w = 0
Gaussova-Jordanova eliminacija: alternativa vstavljanju
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 0 1 0
II−IV III −IV
1 2 0 0 3 0 1 0 0 1 0 0 1 0 1 0 0 0 1 0
I −2II
1 0 0 0 1 0 1 0 0 1 0 0 1 0 1 0 0 0 1 0
I x= 1 II y = 1 III z = 1 IV w = 0
Gaussova-Jordanova eliminacija: alternativa vstavljanju
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 0 1 0
II−IV III −IV
1 2 0 0 3 0 1 0 0 1 0 0 1 0 1 0 0 0 1 0
I −2II
1 0 0 0 1 0 1 0 0 1 0 0 1 0 1 0 0 0 1 0
I x= 1 II y = 1 III z = 1 IV w = 0
Gaussova-Jordanova eliminacija: alternativa vstavljanju
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 0 1 0
II−IV III −IV
1 2 0 0 3 0 1 0 0 1 0 0 1 0 1 0 0 0 1 0
I −2II
1 0 0 0 1 0 1 0 0 1 0 0 1 0 1 0 0 0 1 0
I x= 1 II y = 1 III z = 1 IV w = 0
Gaussova-Jordanova eliminacija: alternativa vstavljanju
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 0 1 0
II−IV III −IV
1 2 0 0 3 0 1 0 0 1 0 0 1 0 1 0 0 0 1 0
I −2II
1 0 0 0 1 0 1 0 0 1 0 0 1 0 1 0 0 0 1 0
I x= 1 II y = 1 III z = 1 IV w = 0
Gaussova-Jordanova eliminacija: alternativa vstavljanju
1 2 0 0 3 0 1 0 1 1 0 0 1 1 1 0 0 0 1 0
II−IV III −IV
1 2 0 0 3 0 1 0 0 1 0 0 1 0 1 0 0 0 1 0
I −2II
1 0 0 0 1 0 1 0 0 1 0 0 1 0 1 0 0 0 1 0
I x= 1 II y = 1 III z = 1 IV w = 0