problem graphing a stat plot....

#1
I tried to graph x^x on my TI 84 and for some reason the positive number came out all right but the negative ones were all messed up. I decided to try and put it in a stat plot, so I filled in numbers from -10 to 10 (not including 0) for L1 and then put in L1^L1 for L2. I ended up getting nonreal ans. After setting the mode to a+bi, L2 came out all right, but when i tried to graph it, i got the error message STAT PLOT. looking in the manual, it says that one of the lists is undefined. I don't think this is possible. Is it? and if not, Why can't I graph the plot?:confused: