I am trying to plot 5 different lines on one graph. Each line is consists of about 500 points. Each point is a temperature value and a resistance value. The X axis is temperature and the Y axis is resistance. Every time I make an XY scatter plot, the range on the x axis is from 0 to 180 even though the data only goes from 77 to 120. If I do a line graph, then the x axis is nicely chosen to be about 77 to 120 but is completely non-uniform. The spacing is completely erratic. I need to have a correct range so I can see the plot and I need even spacing. Why is this so hard?