Question

matlab contour 标注问题

kb=1.38e-23;
T=300;
pi=3.1415926;
w0=2*pi*743;
M=37.25e-6;
g=9.8;
Q=[0.1:0.01:100];
Cmin=[1:1:10].*1e-18;
[X,Y]=meshgrid(Q,Cmin);
BNEA=sqrt(4*kb*T*w0/M./X)/g;
e0=8.85e-12;
A=13.69e-6;
d0=1.5e-6;
Scd=2*e0*A*g/d0^2/w0^2;
CNEA=Y./Scd;
TNEA=(CNEA.^2+BNEA.^2).^0.5;
%surf(X,Y,TNEA)
%meshc(X,Y,TNEA);

[C,h] = contour(X,Y,TNEA,8);
clabel(C,h,'FontSize',10,'Color','r')

。。。。。。。。。。。。。。

不知道怎么控制消暑点的位数，这个标注出来的有效数字太多。想改为小数点后两位。另外科学计数法后面的e-007能否缩短为e-7

Answer 1

'属性可以调整标注的疏密，加入参数'manual'可以手动指定标注的位置。

>> help clabel
CLABEL Contour plot elevation labels.
CLABEL(CS,H) adds height labels to the contour plot specified by H.
The labels are rotated and inserted within the contour lines. CS and H
are the contour matrix output and object handle outputs from CONTOUR,
CONTOUR3, or CONTOURF.

CLABEL(CS,H,V) labels just those contour levels given in
vector V. The default action is to label all known contours.
The label positions are selected randomly.

CLABEL(CS,H,'manual') places contour labels at the locations
clicked on with a mouse. Pressing the return key terminates
labeling. Use the space bar to enter contours and the arrow
keys to move the crosshair if no mouse is available.

CLABEL(CS) or CLABEL(CS,V) or CLABEL(CS,'manual') places
contour labels as above, except that the labels are drawn as
plus signs on the contour with a nearby height value.

H = CLABEL(...) returns handles to the TEXT (and possibly LINE)
objects in H. The UserData property of the TEXT objects contain
the height value for each label.

CLABEL(...,'text property',property_value,...) allows arbitrary
TEXT property/value pairs to specified for the label strings.

One special property ('LabelSpacing') is also available to specify
the spacing between labels (in points). This defaults to 144, or
2 inches.

Uses code by R. Pawlowicz to handle inline contour labels.

Example
subplot(1,3,1), [cs,h] = contour(peaks); clabel(cs,h,'labelspacing',72)
subplot(1,3,2), cs = contour(peaks); clabel(cs)
subplot(1,3,3), [cs,h] = contour(peaks);
clabel(cs,h,'fontsize',15,'color','r','rotation',0)

See also contour, contour3, contourf.

Reference page in Help browser
doc clabel

Answer 2

直接用

[s,h]=contour(X,Y,Z,20);
h_clabel=clabel(s,h)

得到

如果改为

v=[-40:20:160]
[s,h]=contour(X,Y,Z,v
h_clabel=clabel(s,h);  

则变成