|
6 . MatLab.
1. MatLab
.
.
A. , - , - , , :
= [3 1 -1; 2 4 3] = 3 1 -1 2 4 3
. . , :
.
= [4 3 -1
<Enter>. , . . , <Enter>. , :
2 7 0 -5 1 2] B = 4 3 -1 2 7 0 -5 1 2
, -, -. ,
:
= [[3; 4] [-1; 2] [7; 0]] = 3 -1 7 4 2 0
, whos:
2x3 48 double array 3x3 72 double array 2x3 48 double array
, , .
2. MatLab
- , ,
(2, 3) ans = 0
:
(1, 1) + (2, 2) + (2, 3) ans = 5
. m n mn,
[(1,1) (2,1)... (m,1)... (1,n) (2,n)... (m,n)].
, . , ,
[C(1,1) C(2,1) C(1,2) (2,2) (1,3) (2,3)],
. :
(1) ans = 3 (5) ans = 7
3. MatLab: , , ,
, , . , , . , :
S = + S = 6 0 6 6 6 3 R = - R = 0 -2 8 2 -2 -3
, :
S = +??? Error using ==> Matrix dimensions must agree.
:
= * P = -25 9 11 20 26 -4
, , :
= *3 = 9 3 -3 6 12 -3 = 3* = 9 3 -3 6 12 9
, , .', ' . :
' ans = 4 2 -5 3 7 1 -1 0 2
.' ans = 4 2 -5 3 7 1 -1 0 2
1
n m, , , m n: , , . - : , -.
, , :
K= [l-i, 2+3i; 3-5i, l-9i] = 1.0000 1.0000i 2.0000 + 3.0000i 3.0000 5.0000i 1.0000 9.0000iK' ans = 1.0000 + 1.0000i 3.0000 + 5.0000i 2.0000 3.0000i 1.0000 + 9.0000i
K.' ans = 1.0000 - 1.0000i 3.0000 - 5.0000i 2.0000 + 3.0000i 1.0000 - 9.0000i
2
- , . .
^:
2 = ^2 B2 = 27 32 -6 22 55 -2 -28 -6 9
, . , MatLab.
(A + ) 3 (A-).
, , , , .
(+)*^3*(-)' ans = 1848 1914 10290 3612
4.
- - MatLab , , - - . ,
:
a = [1 3 -2]; B = [2 0 1; -4 8 -1; 0 9 2]; c = [-8; 3; 4]; a*B*c ans = 74
5.
, .. , (). . : , , , . , , B, - D, :
= [ ; D] K = -1 4 2 0 -1 4 0 5 3 -3 8 9 -3 3 1 10
, , , - , - D:
= [[; ] [; D]]
. .
, :
1 = (2:3,2:3) 1 = 10 12 11 10
( , ) , . ,
p = P(2,:) p = 4 10 12 5
, end:
p = (2, 2:end) p = 10 12 5
6.
MatLab [ ] , , , . . , , :
= [2 0 3 1 1 4 6 1 3]; M(1,:)=[]; M M = 1 1 4 6 1 3
, size:
size(M) ans = 2 3
. ( ) . M
(:, 2:3) = [] M = 1 6
, .
7.
MatLab. , , . :
.
: 1. T , . 2. . 3. . MatLab .
A(1:5, 1:5) = 0 A= 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 A(1,:) = 1 A= 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 A(end, 3:end) = -1 A= 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 -1 -1 -1
MatLab .
8.
zeros, :
A = zeros(3, 6) A = 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
zeros :
A = zeros(3) A = 0 0 0 0 0 0 0 0 0
eye:
I = eye(4) I= 1 0 0 0 0 1 0 0 0 0 1 0 0 0 0 1
eye , , :
I = eye(4, 8) I = 1 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 1 0 0 0 0
, , ones:
E = ones(3, 7) E = 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
ones , .
MatLab . rand , , randn , :
R = rand(3, 5) R = 0.9501 0.4860 0.4565 0.4447 0.9218 0.2311 0.8913 0.0185 0.6154 0.7382 0.6068 0.7621 0.8214 0.7919 0.1763
rand randn : , .. , . diag - -, :
d = [1; 2; 3; 4]; D = diag(d) D = 1 0 0 0 0 2 0 0 0 0 3 0 0 0 0 4
diag ,
A = [10 1 2; 1 20 3; 2 3 30]; d = diag(A) d = 10 20 30
9.
, , .
, .
.*:
= .* = -2 10 -8 21 -12 -45
./, .\:
R1 = ./1 R1 = -2.0000 2.5000 -0.1250 0.4286 -1.3333 -1.8000 R2 = .\1 R2 = -0.5000 0.4000 -8.0000 2.3333 -0.7500 -0.5556
.^. , , . , .
10.
. , , .. . MatLab spy. G .
spy(G)
spy Figure No. 1. . , (nz = 19). imagesc, . , . colorbar, (Insert ( Figure No. 1), colorbar). , , colormap(gray) (Edit ( Figure No. 1), Colormap, Colormap Editor, Tools, gray). G. , , :
imagesc(G) colorbar colormap(gray)
.
|
: 2016-12-18; !; : 1487 | :
:
. ==> ... 1558 - | 1431 -
© 2015-2024 lektsii.org - - |