基础运算
a = 1/2; //0.5
b = 1-2; //-1
c = 2*pi; //6.2832
d = 2^3;//8
常见数学函数
- exp: exponentiation (e^)
- abs: absolute value
- cos, sin, tan :cosine, sine and tangent
- acos,asin,atan :inverse of cosine, sine and tangent
- cosh,sinh,tanh: hyperbolic functions (also inverses)
- sqrt :square root
- conj :complex conjugate
- fix round :toward zero
- round :round toward nearest integer
- log :natural logarithm
- log10 :base 10 logarithm
- real :real part of complex number
- imag :imaginary part of complex number
矩阵表示
a=[1 2 3;4 5 6];
//1 2 3
//4 5 6
b=[1:1:3] //b = 1 2 3
c=[0:2:10] //c = 0 2 4 6 8 10
d=linspace(-3,3,100); // 返回100个-3~3之间的数
[x,y] = meshgrid(x,y);
a = a.*3; //a中每个数值都 *3
A(2,3) 第二行第三列
A(2,:) 第二行
A(:,3) 第三列
A(1:3,3:4) 1~3行,3~4列
数据传入,保存
可以使用 importdata(‘a.txt’)
或者load上传数据
使用 save 将workplace数据保存到mat文件。
>> A=importdata('Temp.txt')
A =
data: [4x4 double]
textdata: {'R1' 'R2' 'R3' 'R4'}
colheaders: {'R1' 'R2' 'R3' 'R4'}
>> A.data
ans =
88.4000 91.5000 89.2000 77.3000
83.2000 88.0000 67.8000 91.0000
77.8000 76.3000 90.3000 92.5000
92.1000 96.4000 81.2000 84.6000
>> A.textdata
ans =
'R1' 'R2' 'R3' 'R4'
条件语句 if else,switch
if condition1
statements executed if
condition1 is true
elseif condition2
statements executed if
condition2 is true
else
statements executed if
neither condition1 or
condition2 is true
end
switch switch_expression
case case_expression
statements
case case_expression
statements
:
otherwise
statements
end
循环语句 for, while
for count=0:2:20
statement;
end
while (isempty(userString) ||userString=='Y' || userString=='y')
userString = input('Do you want to repeat the loop? y/n :','s');
if (isempty(userString))
userString='Y';
end;
end
函数
自定义函数
function [c] = add(a,b)
c = a+b;
end
图像
>> t=[0:0.01:10];
>> p1=cos(t);
>> p2=sin(t);
>> p3=p1.*p2;
>> plot(t,p1,t,p2,t,p3)
>> title('Example Plot')
>> xlabel('t (seconds)')
>> legend('cos', 'sin','cos(t)*sin(t)')