MATLAB编程练习（含答案很好的）

001双峰曲线图： z=peaks(40); mesh(z); surf(z)

002解方程：

A=[3,4,-2;6,2,-3;45,5,4]; >> B=[14;4;23]; >> root=inv(A)*B

003傅里叶变换 load mtlb ;

subplot(2,1,1); plot(mtlb);

>> title('原始语音信息'); >> y=fft(mtlb); >> subplot(2,1,2); >> yy=abs(y); >> plot(yy);

>> title('傅里叶变换')

004输入函数：

a=input('How many apples\\n','s')

005输出函数

a=[1 2 3 4 ;5 6 7 8;12 23 34 45;34 435 23 34] a =

1 2 3 4 5 6 7 8 12 23 34 45 34 435 23 34 disp(a) a =

1 2 3 4 5 6 7 8 12 23 34 45

34 435 23 34

b=input('how many people\\n' ,'s')

1

how many people two people b =

two people

>> disp(b) two people >>

006求一元二次方程的根 a=1;b=2;c=3; d=sqrt(b^2-4*a*c); x1=(-b+d)/(2*a) x1 =

-1.0000 + 1.4142i

>> x2=(-b-d)/(2*a) x2 =

-1.0000 - 1.4142i

007求矩阵的相乘、转置、存盘、读入数据A=[1 3 5 ;2 4 6;-1 0 -2;-3 0 0]; >> B=[-1 3;-2 2;2 1]; >> C=A*B C =

3 14 2 20 -3 -5 3 -9 >> C=C' C =

2

3 2 -3 3 14 20 -5 -9

>> save mydat C >> clear >> load mydat C

008编写数学计算公式： A=2.1;B=-4.5;C=6;D=3.5;E=-5; K=atan(((2*pi*A)+E/(2*pi*B*C))/D) K =

1.3121

009

A=[1 0 -1;2 4 1;-2 0 5]; >> B=[0 -1 0;2 1 3;1 1 2]; >> H=2*A+B H =

2 -1 -2 6 9 5 -3 1 12

>> M=A^2-3*B M =

3 3 -6 2 13 -2 -15 -3 21

>> Y=A*B Y =

-1 -2 -2 9 3 14 5 7 10

3

>> R=B*A

R =

-2 -4 -1 -2 4 14 -1 4 10

>> E=A.*B E =

0 0 0 4 4 3 -2 0 10

>> W=A\\B W =

0.3333 -1.3333 0.6667 0.2500 1.0000 0.2500 0.3333 -0.3333 0.6667

>> P=A/B P =

-2.0000 3.0000 -5.0000 -5.0000 3.0000 -4.0000 7.0000 -9.0000 16.0000

>> Z=A.\\B

Warning: Divide by zero. Z =

0 -Inf 0 1.0000 0.2500 3.0000 -0.5000 Inf 0.4000

>> D=A./B

Warning: Divide by zero.

4

D =

Inf 0 -Inf 1.0000 4.0000 0.3333 -2.0000 0 2.5000 010

a=4.96;b=8.11;

>> M=exp(a+b)/log10(a+b) M =

4.2507e+005

011求三角形面积： a=9.6;b=13.7;c=19.4; >> s=(a+b+c)/2;

>> area=sqrt(s*(s-a)*(s-b)*(s-c))

area =

61.1739

012逻辑运算

A=[-1 0 -6 8;-9 4 0 12.3;0 0 -5.1 -2;0 -23 0 -7]; >> B=A(:,1:2) B =

-1 0 -9 4 0 0 0 -23

>> C=A(1:2,:) C =

-1.0000 0 -6.0000 8.0000 -9.0000 4.0000 0 12.3000

5