MATLAB: Log of a vector

log

I need a help with taking the log of vector C, however when I do it I get some complex numbers. I understand this happens for the negative element but why all the answers are complex. When I take the log for each element individually I do not see that. Can any help please.
if true
  % code
c = [1.5906       1.4191       1.1537      0.97438       1.6484     -0.29514       1.2085      0.69238]
log (c)
end
This is what I see after taking the log; is there away to show it with out the i for the non-complex case: 0.464128588916044 + 0.00000000000000i 0.349995805662481 + 0.00000000000000i 0.142979230072927 + 0.00000000000000i -0.0259551554779898 + 0.00000000000000i 0.499827232077424 + 0.00000000000000i -1.22030026884339 + 3.14159265358979i 0.189366422721591 + 0.00000000000000i -0.367624437313319 + 0.00000000000000i

Best Answer

A real number is a complex number with an imaginary part equal to 0. If you look at the result of your log you'll see that the complex numbers corresponding to the positive values all have imaginary part of 0.
When an array has at least one complex value (with non-zero imaginary part) matlab will display all numbers in complex notation. There is nothing you can do about that but always remember to look at the imaginary part.
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