Given y, how do I find the value for x?

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I plotted the function:
x = 0:0.01:2;
y=(1.96./x).*(1-exp(-0.83.*x));
I want to know the x value when y=1. I want to use an interp1 function, but that will only give me y values. Is there a function to find x values?
Also, I can't get my x-axis correct. I want it to span 0-2 (the value I'm looking for is around 1.3) with step sizes of 0.001 (for more precision). Currently, it goes 0 to 200 and I'm at a loss of what to do.
Thanks for the help.

Accepted Answer

Andrei Bobrov
Andrei Bobrov on 18 Sep 2013
>> f2 = @(y)arrayfun(@(y)fzero(@(x)1.96./x.*(1-exp(-0.83.*x))-y,1),y);
>> f2([.03 1 12])
ans =
65.333 1.2859 -3.8605
  1 Comment
Will
Will on 18 Sep 2013
Thanks! That gets me the correct answer. However, my matlab understanding is very limited, could you explain a little more how the fzero function and the arrayfun work?
Also, I still have the issue with my x axis being on the wrong order of magnitude.

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