Enveloping multiple plots into one

I have multiple logarithmic plots in a graph that I'd like to envelope them into one consolidated plot. Does anyone know how this task is possible? These plots are representing behavior of a part when exposed to different structural load environments; therefore it's needed to envelope these behavior into one consolidated plot in order to determine the best suitable loading environment for this part? Hope this brief description provides enough information to determine what needs to be done.

Answer 1

[Walter Roberson]

Over the last few weeks, several different people have asked about enveloping. The response that appears to show the most promise is in http://www.mathworks.com/matlabcentral/answers/19817-how-to-create-an-envelope-on-a-tone-burst-signal

[Walter Roberson]

Hmmm... your comment was there for a moment and disappeared.

Please see this list of sites to post images:

http://www.mathworks.com/matlabcentral/answers/7924-where-can-i-upload-images-and-files-for-use-on-matlab-answers

[Aviator]

Thanks!!

However, none of the presented enveloping approaches can be applied to my specific problem. I have multiple plots that may or may not create junction points and they're not of the sinusoidal/periodic nature. I have a sample picture of one the graphs I generated but don't have an option here to upload it for further clarification.

[Walter Roberson]

Upload it to one of the sites listed above, and then post the link to it here.

[Aviator]

http://imgur.com/QRbLl

[Walter Roberson]

In that particular image, it appears that the upper line would make an acceptable upper envelope -- but could you describe what you would like the lower envelope to look like? Are you looking for an envelope that just follows the max() of all of the plots on top, and the min() of all of the plots on bottom? Is every line defined over the whole range of X, or is would it be necessary to interpolate sparse (x,y) pairs into straight lines ?