形成的曲面网线图。
16、请在同一窗口画出两条曲线,y1=sin(x),y2=cos(x),要求添加网格线,x轴标注IndependentVariableX,y轴标注DependentVariableY1&Y2,标注标题SineandCosineCurve,在(1.5,0.3)处标注cos(x),坐标轴设定在x轴[0,2Π],y轴[-0.9,0.9]。
答案
1、>>A=[234;541;132];
>>U=[123]';
>>X=A\U
X=
-0.8148
1.6667
-0.5926
2、
>>t=[00.30.81.11.62.3]';
>>y=[0.820.720.630.600.550.50]';
>>E=[ones(size(t))exp(-t)];
>>C=E\y
C=
0.4760
0.3413
>>x=0:
0.01:
2.5;
>>z=0.4760+0.3413*exp(-x);
>>plot(t,y,'O',x,z,'r:
')
3、
>>A=[3105;0-673;0430;2-126];
>>Y=[2478]';
>>X=A\Y
X=
-4.8247
1.3944
0.4741
3.0159
4、
>>t=[12345678910]';
>>y=[4.8424.3623.7543.3683.1693.0833.0343.0163.0123.005]';
>>E1=[ones(size(t))exp(-t)];
>>C=E1\y
C=
3.1621
5.1961
>>E2=[ones(size(t))t.*exp(-t)];
>>D=E2\y
D=
3.0039
5.0046
>>x=1:
0.01:
10;
>>y1=3.1621+5.1961*exp(-x);
>>y2=3.0039+5.0046*x.*exp(-x);
>>plot(t,y,'O',x,y1,'r:
',x,y2,'b-')
>>p1=polyfit(t,y,2)
p1=
0.0411-0.63835.3937
>>p2=polyfit(t,y,3)
p2=
-0.00410.1085-0.94935.7443
>>y3=polyval(p1,x);
>>y4=polyval(p2,x);
>>plot(t,y,'O',x,y3,'r:
',x,y4,'b-')
6、
>>t=[00.20.40.60.81.02.05.0]';
>>y=[1.01.511.882.132.292.402.60-4.00]';
>>p=polyfit(t,y,4)
p=
-0.09930.7935-2.28412.98820.9995
>>E=[ones(size(t))exp(-t)];
>>C=E\y
C=
-0.0565
2.5674
>>x=0:
0.001:
5;
>>y1=-0.0565+2.5674*exp(-x);
>>y2=polyval(p,x);
>>plot(t,y,'O',x,y1,'r:
',x,y2,'b-')
7、
•001functioncompare_interp()
•002%COMPARE_INTERP不同插值运算的比较
•003
•004%原始数据
•005[x,y]=meshgrid(?
3:
1:
3);
•006z=peaks(x,y);
•007figure
(1);clf
•008surfc(x,y,z);
•009title('原始数据')
•010%进行插值运算
•011[xi,yi]=meshgrid(?
3:
0.25:
3);
•012zi1=interp2(x,y,z,xi,yi,'nearest');
•013zi2=interp2(x,y,z,xi,yi,'linear');
•014zi3=interp2(x,y,z,xi,yi,'cubic');
•015zi4=interp2(x,y,z,xi,yi,'spline');
•016%通过可视化结果比较
•017figure
(2)
•018subplot(2,2,1);surf(xi,yi,zi1);
•019title('二维插值-''nearest''')
•020subplot(2,2,2);surf(xi,yi,zi2);
•021title('二维插值-''linear''')
•022subplot(2,2,3);surf(xi,yi,zi3)
•023title('二维插值-''cubic''')
•024subplot(2,2,4);surf(xi,yi,zi4)
•025title('二维插值-''spline''')
•026%可视化结果
•027figure(3)
•028subplot(2,2,1);contour(xi,yi,zi1)
•029title('二维插值-''nearest''')
•030subplot(2,2,2);contour(xi,yi,zi2)
•031title('二维插值-''linear''')
•032subplot(2,2,3);contour(xi,yi,zi3)
•033title('二维插值-''cubic''')
•034subplot(2,2,4);contour(xi,yi,zi4)
•035title('二维插值-''spline'''')
•
8、
>>x=-pi:
pi/4:
pi;
>>y1=sin(x);
>>y2=cos(x);
>>y3=sinh(x);
>>y4=cosh(x);
>>plot(x,y1,'rO:
',x,y2,'b*-',x,y3,'gs--',x,y4,'k^-.')
9、
>>X=[19.322.151.6;34.270.382.4;61.482.990.8;50.554.959.1;29.439.347];
>>x=sum(X)
x=
194.8000269.5000330.9000
>>explode=[001];
>>pie(x,explode)
10、
>>t=[00.30.81.11.62.3]';
>>y=[0.50.821.141.251.351.40]';
>>E=[ones(size(t))exp(-t)t.*exp(-t)]
E=
1.00001.00000
1.00000.74080.2222
1.00000.44930.3595
1.00000.33290.3662
1.00000.20190.3230
1.00000.10030.2306
>>A=E\y
A=
1.3974
-0.8988
0.4097
>>x=0:
0.01:
2.5;
>>Y=1.3974-0.8988*exp(-x)+0.4097*x.*exp(-x);
>>plot(t,y,'O',x,Y,'r-')
11、
A=struct('name',{'江明顺','于越忠','邓拓'},'NO',{'071023','060134','050839'});
A
(1).level=struct('height','176','weight','82')
A=
1x3structarraywithfields:
name
NO
level
>>A
(2).level=struct('height','168','weight','74')
A=
1x3structarraywithfields:
name
NO
level
>>A(3).level=struct('height','182','weight','77')
A=
1x3structarraywithfields:
name
NO
level
12、
>>B=cell(1,2);
>>B{1,1}=struct('date','2007/06/04','billing',[125.7389.3;254.9538.5])
B=
[1x1struct][]
>>B{1,2}=struct('name','maggie','profession','teacher','hobby','dance')
B=
[1x1struct][1x1struct]
>>cellplot(B)
13、
>>year=1990:
2:
2010;
>>product=[75.99591.972105.711123.203131.669150.697179.323203.212226.505249.633256.344];
>>p1999=interp1(year,product,1999,’spline’)
>>x=1990:
1:
2010;
>>y=interp1(year,product,x,'spline');
>>plot(year,product,'*',x,y)
14、
>>X=[2.55.07.510.013.017.020.030.040.050.060.070.0];
>>Y=[0.290.560.771.051.361.522.002.272.813.053.253.56];(
>>P=polyfit(X,Y,3);
>>x=2.5:
0.1:
70;
>>y=polyval(P,x)
>>plot(X,Y,’O’,x,y)
>>girdon
15、
>>clear
>>x=-2:
0.2:
2;
>>y=-2:
0.2:
2;
>>[X,Y]=meshgrid(x,y);
>>Z=X.*exp(-X.^2-Y.^2);
>>mesh(X,Y,Z)
16、
》x=0:
pi/10:
2*pi;
》y1=sin(x);
》y2=cos(x);
》plot(x,y1,x,y2) ;
》gridon
》xlabel(‘IndependentVariableX’);
》ylabel(‘DependentVariableY1&Y2’);
》title(‘SineandCosineCurve’)
》text(1.5,0.3,’cos(x)’);
》axis([02*pi-0.90.9])