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GRAPHING
Scientific Data on a Line Graph

You want to use as much of the graph as possible so that you can see any patterns.

Let's do the x-axis first.

  1. Count the number of lines the axis has: count like moving on a board game, don't count the first line. On this graph there are 20 lines on the x-axis.
  2. Determine the maximum value to be plotted on the x-axis. For this data the maximum temperature was 80 oC.
  3. Set up a ratio of maximum data value to number of lines:
   this reduces to 4 oC for every 1 line
  1. You probably do not want to label every line and there is really no use. So let's label every 4 lines, that would be 16 oC for every 4 lines. But our data for temperature is every 20 oC, so we probably want to label every 20 oC. In order to do this you would label every 5 lines. The idea is to label the axis quickly and conveniently without trial and error.
    1. NOTE: The data used here is designed to work out in a nice reducible fraction. If your ratio was not reducible to whole numbers simply divide out to get a value, maybe it was 4.4274 oC for every 1 line. Simply round up till you find something easy to use in scaling your axis. I would choose 4.5 oC for every line here, or 9 oC for every 2 lines. I should be able to label fairly easily with those values.
  2. Back to our example. Scale the axis:

Now do the same for the y-axis.