目录
1 数据分析函数库
%例1.1
data=[49 99 100 63 63 55 56 89 96 60]';
a=max(data)
b=min(data)
m=mean(data)
s=sum(data)
c=std(data) 
%例1.2
y= 5*(randn(1,10)-.5)
plot(y) 
%例1.3
x= rand(1,10)
y= rand(1,10)
corrcoef(x,y) %结果
x =
0.7060 0.0318 0.2769 0.0462 0.0971 0.8235 0.6948 0.3171 0.9502 0.0344
y =
0.4387 0.3816 0.7655 0.7952 0.1869 0.4898 0.4456 0.6463 0.7094 0.7547
ans =
1.0000 -0.0403
-0.0403 1.0000
2 多项式函数库
%例2.1
a=[2, 4, 6, 8]
b=[3, 6, 9]
c=a+[0, b]
d=conv(a,b) [q,r]=deconv(d,a) [q,r]=deconv(a,b)%结果
c =
2 7 12 17
d =
6 24 60 96 102 72
q =
3 6 9
r =
0 0 0 0 0 0
q =
0.6667 0
r =
0 0 0 8%例2.2
a=[2, 4, 6, 8]
a1=polyder(a)
a2=roots(a)
a3=poly(a2)
a4=polyval(a,1)
%结果
a =
2 4 6 8
a1 =
6 8 6
a2 =
-1.6506 + 0.0000i
-0.1747 + 1.5469i
-0.1747 - 1.5469i
a3 =
1.0000 2.0000 3.0000 4.0000
a4 =
20%例2.3
x=(0:0.1:1)
y=[0.447,1.978,3.28,6.16,7.01,7.32,7.66,9.56,9.48,9.30,11.2]
a1=polyfit(x,y,1);
xi=x
yi1=polyval(a1,xi);
plot(x,y,'o',xi,yi1,'b') 
3 非线性函数分析及函数的数值积分
function y=humps(x)
y= 1./((x-0.3).^2+0.01)+1./((x-.9).^2+.04)-6;
fplot('humps',[0, 2]),grid
z=fzero('humps',1)
s=quad('humps',1,2) 
%结果
z =
1.2995
s =
-0.5321
