Finding mimum of a function with 2 local mins

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The discussion revolves around finding the minimum of a non-analytic function with two local minima. The steepest descent method with numerical gradients is suggested for optimization, but the choice of starting point significantly affects the outcome. If the starting point is near one local minimum, it will lead to that minimum rather than the global one. The challenge lies in not knowing the location of the tall peak, complicating the selection of an appropriate starting point. A consistent method to identify the actual lowest point remains a key concern.
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I have a function that looks like this:
http://rpi.edu/~doriad/view1.jpg The function is non analytic, so I have to use something like the steepest descent method with numerical gradients to find the minimum. However, if my starting point is on the left of the tall peak, the min I find is on the left side (clearly) and if I choose the starting point to be on the right side I find the low point on the right. Clearly in this case I could just do both and take the smaller one, but if I'm not sure about the location of the tall peak to start with, I can't simply choose a starting point on either side. Is there a way to find the actual lowest point consistently?

Thanks,

David
 
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Hi David,

I think it would be a lot better if you could provide an image of the function to make it all much more clear.
 
The image has been posted.
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