C=a*b, a= [2;3;4] b=[1;2;3] d=a.*b
C=[2;3;4]*[1;2;3]=[2*1;3*2;4*3]=[2;6;12] d=[2;6;12]
a.*b, a./b, a.^b ooeeeoepa! ! , , ,
22. // / /
. .
C=A*B= * =
23. Y = inv(A) , A.
Inv(A)=inv =
24. eig(A).
= eig (), eig (), -, , [u, D] = eig () , , D .
25. max(A) min(A).
:
Y = max(X)
[Y, I] = max(X)
C = max(A, B)
:
Y= max(X) ; - -, . , max(max(X)) - .
[Y, I] = max(X) - .
C = max(A, B) C , A B, .
, max(abs(X)). NaN, NaN.
:
M = magic(3).
M = | 8 | 1 | 6 | |
3 | 5 | 7 | ||
4 | 9 | 2 |
y = max(M) | [y, I] = max(M) | max(max(M)) |
y = 8 9 7 | y = 8 9 7 I = 1 3 2 |
26. dot(a,b) sum(a.*b)
:
sx = sum(X)
csx = cumsum(X)
:
sx = sum(X) ; - -, .
csx = cumsum(X), , .
:
M = magic(3): M = magic(3)
M = | 8 | 1 | 6 | |
3 | 5 | 7 | ||
4 | 9 | 2 |
cumsum(M) | sum(M) | |||||||||
|
v = dot(a, b); ,
|
|
27. for.
Syntax
for =
End
. , (), 1 N 1, N . , a b step. . , , for, .
for :
for <> = < >:<>:< >
< >
end
:
a = [3 6 5 3 6 9 5 3 1 0];
m = a(1); %
for i=1:length(a) % 1
% 1 ( )
if m < a(i) % a(i) > m,
m = a(i); % m = a(i)
end
end % for
disp(m);
for i 1 10 1.
28. while
:
while <>
<>
end
<> , if, while , .
, , , , .
while :
S = 0; %
i=1; %
while i <= 20 % ( i <= 20)
S=S+i; %
i=i+1; % 1
end %
disp(S); % 210
29.
MATLAB 6 :
<
<=
>
> =
==
~ =
. , , . MATLAB . , , 1, - 0.
, , . if, for, while, switch.
.
.
, <B:
A = [2 7 6; 9 0 -1; 3 0.5 6];
B = [8 0.2 0; -3 2 5; 4 -1 7];
< B
ans =
1 | 0 | 0 |
0 | 1 | 1 |
1 | 0 | 1 |
30. .
MATLAB :
& | |
| | |
~ |
, bitfun , .
|
|
. , , . MATLAB . , , 1, - 0.
, :
AND (&) , - . , , .
:
u = [1 0 2 3 0 5];
v = [5 6 1 0 0 7];
AND (&):
U & v
ans =
1 | 0 | 1 | 0 | 0 | 1 |
OR (|) , . , .
, , .
u v, , OR (|):
U | v
ans =
1 | 1 | 1 | 1 | 0 | 1 |
NOT (~) . , , , . , , , , .
u, NOT (~):
~ u
ans =
0 | 1 | 0 | 0 | 1 | 0 |
31. if .
if :
if <>
<>
end
, , . , , . . 2.1 if.
2.1.
if a < b | , a b . |
if a > b | , a b . |
if a == b | , a b . |
if a <= b | , a b . |
if a >= b | , a b . |
if a ~= b | , a b . |
32. switch.
. , . , . switch, :
switch expr
case case_expr,
<1>
case {case_expr1, case_expr2, case_expr3,...}
<2>
otherwise,
<>
end
:
ch='c';
switch ch
case 'a', ch='A';
case 'b', ch='B';
case 'c', ch='C';
case 'd', ch='D';
case 'e', ch='E';
case 'z', ch='Z';
end
disp(ch);
33. plot()
, plot() :
x = 0:0.01:pi;
y1 = sin(x);
y2 = cos(x);
plot(x,y1,x,y2);
34. plot(y) y ; y , plot(real(y), imag(y)). Y - , ; .
|
|
plot(x, y) , x , y - . X Y , :
Y , x , Y x;
X, y , X y;
X Y , Y X.
35. - . get, . .
, , 2. , 2 LineWidth:
W = get(hL, 'LineWidth')
set(hL, 'LineWidth', W+2)
36. set, , '' - :
set(h, '', )
:
set(h, '1', 1, '2', 2,:)
: (5) , plot:
hL = plot(x,y)
hL LineWidth :
set(hL, 'LineWidth',5)
37. , . subplot(), :
subplot(< >, < >, < >)
38. title()
xlabel , ylabel -
:
x=-3*pi:pi/100:3*pi;
y=-3*sin(x+pi/3);
plot(x,y), grid
title( y=3sin(x+π/3));
xlabel(x); ylabel(y)
39. text
Text(x, y, text)
40. fopen() . - , . fopen(). " File ". , :
" r " - ,
" w " - ,
" a " - .
, . " r " . , , . "w" , , .
.
|
|
FILE *in;
in=fopen("File","r");
in " File ". in, File
41 fscanf . , . - , .
fscanf:
fscanf(f, "%d", &n); //
fscanf(f, "%lf", &a); //
fscanf(f, "%c", &c); //
fscanf(f, "%s", str); // (
// )
fscanf(f, "%d%d", &n, &m); //
42. fprintf() . , :
str = 'Hello';
y = 10;
count = fprintf(fid, '%d %s ', y, str);
:
10
Hello
fprintf
. fprintf :
fprintf(_,A1,..., An)
_ , . , . , (A1,..., An). \ %. .
fprintf().
43.
fscanf . (.. , , ). fscanf . , . - , .
fprintf . . , fscanf, , , , . , fscanf, "%". , fscanf. , fprintf , , , , .
44,45,46 d, f, e
.
%d | ( ) |
% | "" , 3.1415 + 00 |
%f |
. . 19.3.
19.3. .
"" (-) | %-5.2d | |
"" (+) | (+ ) | %+5.2d |
(0) | %05.2d | |
, | %6f | |
( ) | , | %6.2f |
47.
.
|
|
\n | |
\t | |
\b | ( ) |
\r | |
\f | |
\\ | ( ) |
\" " | |
%% |