While Loop Problem Displaying NaN
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So I am trying to make a while loop which finds the value of log(x+1) using a taylor series. I am having the series run until the answer comes into a certain precision. When I run the function with x=1 I get the correct out for both y and i. However if I try it with any greater number the y value displays as NaN. Can anyone help me figure out how to fix this.
function logoneplusx(x)
format long
y=0;i=1;Err=1;
while Err>0.001
y=((-1)^(i-1))*((x^i)/i)+y;
i=i+1;
Err=abs(y-log(x+1));
end
disp(y)
disp(i)
回答（2 个）
Azzi Abdelmalek
2014-7-15
编辑：Azzi Abdelmalek
2014-7-15
0 个投票
When x is bigger, y becomes infinite, and after you have Err=(inf-inf)=NaN. Matlab or another software has its limits.
James Tursa
2014-7-15
0 个投票
If you check this link, you will see that the series you are using only converges for abs(x) <= 1 and x not equal to -1:
If you want to use an x value outside this convergence range, use a different series. On this same link there is another series you can use for other values of x.
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2014-7-15
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