Лабораторная № 1
.docx
>> A=[2 -1 3 -5; 1 4 5 -1; 1 -5 -2 -4; 3 -6 1 -9]
A =
2 -1 3 -5
1 4 5 -1
1 -5 -2 -4
3 -6 1 -9
>> B=[7; 8; -1; 6]
B =
7
8
-1
6
>> C=A*B
C =
-27
28
-55
-82
>> X=A\B
Warning: Matrix is singular to working precision.
X =
Inf
Inf
Inf
Inf
>>
>> d=det(A)
d =
0
>> A=[2 -1 5 -5; 1 4 5 -1; 1 -5 -2 -4; 3 -6 1 -9]
A =
2 -1 5 -5
1 4 5 -1
1 -5 -2 -4
3 -6 1 -9
>> d=det(A)
d =
0
>> A=[2 -1 5 -5; 3 4 5 -1; 1 -5 -2 -4; 3 -6 1 -9]
A =
2 -1 5 -5
3 4 5 -1
1 -5 -2 -4
3 -6 1 -9
>> d=det(A)
d =
84
>> X=A\B
X =
-0.0000
1.5714
0.0000
-1.7143
>> A*X
ans =
7.0000
8.0000
-1.0000
6.0000
>> A=[2 -1 5 -5; 3 4 5 -1; 1 -5 -2 -4; 3 -6 1 -9]
A =
2 -1 5 -5
3 4 5 -1
1 -5 -2 -4
3 -6 1 -9
>> D=inv(A)
D =
0 0.5000 1.0000 -0.5000
-0.5238 -0.0714 -1.0952 0.7857
0.5000 0 0.5000 -0.5000
0.4048 0.2143 1.1190 -0.8571
>> A*D
ans =
1.0000 -0.0000 -0.0000 0.0000
0 1.0000 -0.0000 0.0000
0 0 1.0000 0
-0.0000 0 0 1.0000
>> inv(A)*B
ans =
0
1.5714
0.0000
-1.7143
>> A(1:2, 1:3)=0
A =
0 0 0 -5
0 0 0 -1
1 -5 -2 -4
3 -6 1 -9
>> A=[2 -1 5 -5; 3 4 5 -1; 1 -5 -2 -4; 3 -6 1 -9]
A =
2 -1 5 -5
3 4 5 -1
1 -5 -2 -4
3 -6 1 -9
>> C=A*D
C =
1.0000 -0.0000 -0.0000 0.0000
0 1.0000 -0.0000 0.0000
0 0 1.0000 0
-0.0000 0 0 1.0000
>> E=eye(4,4)
E =
1 0 0 0
0 1 0 0
0 0 1 0
0 0 0 1
>> C>D
ans =
1 0 0 1
1 1 1 0
0 0 1 1
0 0 0 1
>> C>E
ans =
0 0 0 1
0 0 0 1
0 0 0 0
0 0 0 0
>> C<=D
ans =
0 1 1 0
0 0 0 1
1 1 0 0
1 1 1 0
>> C&E
ans =
1 0 0 0
0 1 0 0
0 0 1 0
0 0 0 1
>> C==E
ans =
0 0 0 0
1 0 0 0
1 1 1 1
0 1 1 1