Đồ họa1
1. clc
2. clear
3. x=[2:0.1:6];
4. y=sin(x);
5. plot(x,y,'gp',x,y,'cs',x,y,'r-*') %c la mau xanh
xam p la hinh da giac polygon
6. xlabel('Truc hoanh')
7. ylabel('Truc ttung')
8. grid
9. text(4,0,'Quang Vuong')
10. gtext('dep trai') %matlab se dua ra toa do ngam de
dat xau vao
11. legend('hoc dot','gia nua')
% them chu thich vao
doo thi, co the di chuyen di khap do thi
a. %'hoc dot':se chu thich cho do thi 1
b. %'gia nua': se chu thich cho do thi 2
12. title('Do thi vi du cho Do Hoa Matlab')
Đồ họa2
1. clc
2. clear
3. x=linspace(0,2*pi,30);
4. y=sin(x);
5. z=cos(x);
6. subplot(1,3,1)
7. plot(x,y);
8. subplot(1,3,3)
9. plot(x,z,'m')
10. subplot(1,3,2)
11. plot3(y,x,y)
Đồ họa 3:
clc
clear
t=linspace(5,15);
subplot(1,2,1);
plot3(sin(t),cos(t),t,'pr')
view([100,70])
*Cac phep toan co ban
clc
clear
%CacPhepToanCoBanTrongMatlab
5/4 %Chia phai kq=1,25
5\4 %Chia trai kq=0,8
2^3 %luy thua
,
%chuyen vi ma tran hay so phuc lien hop
%Cac toan tu quan he:
%< <= > >= == bang ~= khong bang
%Cac toann tu logic:
% & va | or ~ not
%Cac hang so:
%pi 3,14159265
% i
so ao
% j tuong tu i
% eps sai so 2^-52
% realmin
:sothuc nho nhat 2^-1022
%realmax
:sothuc lon nhat 2^1023
%inf
:vo cung lon
%NaN
:not a number
Giai ax +b =0
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%Giai phuong trinh ax+b=0
clc
a=input('a=');
b=input('b=');
if a==0
if b==0
disp('phuong trinh vo so nghiem')
else
disp('phuong trinh vo nghiem')
end
else
x=-b/a;
disp(x)
end
*Giai phuong trinh 2 an:
clc
a=input('a=');
b=input('b=');
c=input('c=');
if(a==0)
if b==0
if c==0
disp('phuong trinh vo so nghiem')
else
disp('phuong trinh vo nghiem')
end
else
x=-c/b;
disp(x)
end
else
delta=b*b-4*a*c;
if((delta)>0)
disp('Phuong trinh da cho co 2 nghiem:')
x1=(-b+sqrt(delta))/(2*a);
x2=(-b-sqrt(delta))/(2*a);
disp(x1)
disp(x2)
else
if((delta)<0)
disp('\nPhuong trinh da cho vo nghiem vi delta <0')
else((delta)==0)
disp('\nPhuong trinh co nghiem kep:')
x=-b/(2*a);
disp(x)
end
end
end
*Giai he
%Giai he phuong trinh bac nhat 2 an:
%a1X + b1Y = c1
%a2X + b2Y = c2
clc
fprintf('Giai phuong he phuong trinh 2 an: \na1X + b1Y = c1\na2X + b2Y = c2')
fprintf('\nNhap vao he phuong trinh bac nhat 2 an:\n')
a1=input('a1=');
b1=input('b1=');
c1=input('c1=');
a2=input('a2=');
b2=input('b2=');
c2=input('c2=');
d=a1*b2-a2*b1;
d1=c1*b2-c2*b1;
d2=a1*c2-a2*c1;
if (d==0 & d1==0 & d2==0)
disp('He phuong trinh vo so nghiem')
else
if(d==0 & (d1==0 | d2==0))
disp('He phuong trinh vo nghiem')
else
disp('He phuong trinh da cho co nghiem:')
x=d1/d;
y=d2/d;
fprintf('\nX = %d',x)
fprintf('\nY = %d\n',y)
end
end
Khai bao ma tran
clc
clear
a=[1 2 4; 5 7 23]
%Matran 2 hang 3 cot
a(1)
%lay ra phan tu thu 1 trong ma tran
a(3)
%lay tra phan tu thu 3 cua ma tran, chu y matlab dem tu tren xung roi
sang hang khac
length(a)
%ham length chi ra kich thuoc lon nhat cua hang hoac cot
%neu hang hoac cot dai hon thi chi ra kich thuoc lon hon
size(a) %chi ra kich thuoc ma tran a dang 2*3
5>4
%Dung nen matlab tra ve ket qua 1
5>4 & 6>7
%sai o 6>7 nen matlab tra ve ket qua 0 AND
5>4 | 6>7
%chi can 1 trong hai dung thi cho ket qua dung 1 OR
Khai báo véc tơ
clc
clear
b=[7:1:20]
i=[1:10]
b=[i:1:20]
c=[i 2 1]
d=length(c)
%[phantudau : khoangcach : phantucuoi]
%Neu ta khong ghi khoang cach may mac dinh khoang cach bang 1
%May se cong tiep day i den 20
%May se them hai phan tu 2 va 1 vao mang i
%Cho biet so phan tu cua mang c
Săp xếp mảng
%Sap xep mang theo thu tu giam dan
clc
clear
disp('So gia tri n ban se nhap la:')
n=input('n=');
for i=[1:n]
a(i)=input('Gia tri thu i =');
end
for i=[1:n-1]
for j=[i+1:n]
if a(i)
tg=a(i);
a(i)=a(j);
a(j)=tg;
end
end
end
disp('Day duoc sap xep lai:' )
for j=[1:n]
disp(a(j))
end
>0 và chia het 3
clc
clear
disp('Nhap vao gia tri:')
n=input('n=');
for i=[1:n]
fprintf('gia tri thu %d ',i)
a(i)=input('la:');
end
dem=0;
s=0;
for i=[1:n]
if a(i)>10 & rem(a(i),3)==0
s=s+a(i);
dem=dem+1;
end
end
tbc=s/dem
Tìm max
%VD8.Nhap vao mang, dua ra gia tri lon nhat va vi tri cua no
clc
clear
disp('Ban se nhap n gia tri:');
n=input('n=');
for i=[1:n]
fprintf('Gia tri thu %d ',i);
a(i)=input('la: ');
end
max=a(1);
vitri=0;
for i=[2:n]
if a(i)>max
max=a(i);
vitri=i;
end
end
disp('Gia tri lon nhat cua mang la:')
max
disp('O vi tri:')
vitri
TBC của ma trận
%VD9: Nhap vao so nguyen kich thuoc [n:m] voi n, m nhap tu ban phim
%a, tinh trung binh cua ma tran
%b,Dem xem o cot 1 co bao nhieu phan tu chi het cho 3
%c,Nhap k tu ban phim voi 0
clc
clear
disp('Ma tran n*m ban se nhap tu ban phim co:');
n=input('n=');
m=input('m=');
for i=[1:n]
for j=[1:m]
fprintf('\nGia tri thu %d*%d',i,j)
a(i,j)=input(' la: ');
end
end
tong=0;
for i=[1:n]
for j=[1:m]
tong=tong+a(i,j);
end
end
tbc=tong/(m*n);
disp('Trung binh cong:')
tbc
% phan b)
dem=0;
for i=[1:n]
if rem(a(i,1),3)==0
dem=dem+1;
end
end
disp('So phan tu chia het cho 3 la:')
dem
%phan c)
disp('nhap so hang can sap xep')
k=input('k=');
for i1=[1:n-1]
%i va j o day khong phai la hang va cot nua ma la..
for j1=[i1+1:m]
if a(k,i1)>a(k,j1)
tg=a(k,i1);
a(k,i1)=a(k,j1);
a(k,j1)=tg;
end
end
end
for j1=[1:m]
disp(a(k,j1));
end
XYZ
clc
clear
x=[-20:0.1:20];
y=x;
[x,y]=meshgrid(x,y);
a=sqrt(x.^2+y.^2);
z=sin(a)./a;
mesh(x,y,z)