【求助】关于等值线一问 - MATLAB爱好者论坛-LabFans.com

bbflying · 2008-03-17, 16:26

我想画z=1/x+1/y。，然后想知道x和y落入哪个区域时，z>=1；也就是说画等值线的时候，我想只画两条，对Z值做个判断，大于等于1还是小于1。这个应该怎么实现啊？谢谢大家了

zhiwei · 2008-03-19, 00:48

>> clear all
>> [X,Y] = meshgrid(-2:.01:2,-2:.01:2);
>> Z=1./X+1./Y;
Warning: Divide by zero.
Warning: Divide by zero.
>> figure(1),mesh(X,Y,Z)
>> figure(2),contour(Z,1)
??? Error using ==> contourc
Contour levels must be finite.

Error in ==> specgraph.contourgroup.schema>LdoDirtyAction at 256
refresh(h);

??? Error occurred while evaluating listener callback.

>> figure(2),contour(Z,.99)

2008-03-17, 16:26	#1
bbflying 初级会员注册日期: 2008-02-19 年龄: 41 帖子: 1 声望力: 0	【求助】关于等值线一问我想画z=1/x+1/y。，然后想知道x和y落入哪个区域时，z>=1；也就是说画等值线的时候，我想只画两条，对Z值做个判断，大于等于1还是小于1。这个应该怎么实现啊？谢谢大家了

相似的主题
主题	主题作者	版面	回复	最后发表
[求助]神经网络的错误	wangzhenhua0419	MATLAB论坛	2	2009-06-15 19:40
哪位高手搞过matlab 仿真拉杆天线啊	ghost1861	MATLAB论坛	0	2008-04-27 17:30
华南虎研究者通过模拟实验证明虎照作假	labfans	MATLAB新闻聚合	0	2007-11-20 15:15
【资料】CDMA2000 Downlink Simulink Models CDMA2000下行链路仿真模块	yesman	MATLAB论坛	2	2007-06-28 15:38
【求助】请教用dsolve求解符号微分方程中的参数传递问题	frcarpin	MATLAB论坛	0	2007-06-21 14:33

2008-03-19, 00:48	#2
zhiwei 初级会员注册日期: 2008-03-15 年龄: 43 帖子: 7 声望力: 0	>> clear all >> [X,Y] = meshgrid(-2:.01:2,-2:.01:2); >> Z=1./X+1./Y; Warning: Divide by zero. Warning: Divide by zero. >> figure(1),mesh(X,Y,Z) >> figure(2),contour(Z,1) ??? Error using ==> contourc Contour levels must be finite. Error in ==> specgraph.contourgroup.schema>LdoDirtyAction at 256 refresh(h); ??? Error occurred while evaluating listener callback. >> figure(2),contour(Z,.99)