9

I want to make a scatterplot with Gnuplot of these data (1st column as x-coordinates):

2015.493379 5 
2015.505479 5 
2015.513699 25 
2015.530137 25 
2015.532877 20 
2015.543836 5 
2015.552055 5 
2015.554795 10 
2015.563014 15 
2015.565753 15 
2015.582192 10

I'm using this command:

plot "file.txt" u 1:2

The problem is the x-axis precision: when I hover over my points between 2015.53 and 2015.54, the x-value displayed is 2015.53 for both points, instead of 2015.530137 and 2015.532877. gnuplot truncates the first column numbers at the first two decimals (2015.49, 2015.50, etc). I tried to change the x format (format x %.6f for ex) but it does not change the precision: x-tics just become 2015.490000, etc instead of 2015.49, whereas I want 2015.493379, etc, and the mouse pointer does not give extra information (in the bottom-left corner, the coordinates of the point pointed by the mouse have the same precision).

Do you know how to tell gnuplot to take the entire number into account ?

scjorge
  • 361
JoVe
  • 145

1 Answers1

11

Instead of changing the format of tics, change the format of the axis

set format x "%.6f"

You might then need to set the xtics format to a different one

set xtics format "%.4f"

If you want to change where xtics start and how often they tic, use the following syntax:

set xtics 2015.49337, 0.01

To change the format of the coordinates shown for the mouse pointer, use the mouse option:

set mouse format '%.6f'
choroba
  • 47,233
  • I used this command to change the format of tics, and it does what I've described in the first post – JoVe Jul 28 '15 at 12:41
  • @JoVe: Oh, you mean you want to change where xtics start? Check the update. – choroba Jul 28 '15 at 12:47
  • No that's not what I meant. I want to change the precision of the numbers displayed. When I move the mouse pointer on the graph, the (x,y) coordinates are displayed in the bottom left corner: they are truncated at the 2nd decimal (2015.xx instead of the 2015.xxxxxx I want). And the same is done with the tics (2015.xx0000 when I force gnuplot to display more digits). I need a higher precision to know which point corresponds to what. Am i clearer ? – JoVe Jul 28 '15 at 13:03
  • @JoVe: I still don't get it. If a tic corresponds to 2015.51, why should it display any non-zero digits after the 1 at the end? – choroba Jul 28 '15 at 13:11
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    Okay, the value of the tic is not important. Let's assume the tics are 2015.49, 2015.50 etc. I have two points between 2015.53 and 2015.54: I want to know the exact value (as wirtten in my data file) of the x-coordinate of one point when I hoover my mouse over it. Gnuplot displays the coordinates of the mouse pointer in the bottom-left corner, but the precision is the same as the x-tics. Thus, when I hover over my points between 2015.53 and 2015.54, the x-value displayed is 2015.53 for both points, instead of 2015.530137 and 2015.532877. – JoVe Jul 28 '15 at 13:20
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    @JoVe: Oh, I understand now. Check the edit. – choroba Jul 28 '15 at 13:28
  • Ok many thanks, that is exactly what I need, sorry I was not clear enough. – JoVe Jul 28 '15 at 13:35