I try to plot contour with only one cntrlabel per line but I do not succeed. I tried
set cntrlabel onecolor start 50 interval 10000000
and
set cntrlabel onecolor start 50 interval -1
but it does not work. Is there a mean to force 1 label per line ?
Moreover, I would like to shift the cntrlabel in order to prevent them to be overlayed (as observed on the top-left of the graph with the label 45, 50, 55, and 60). How should I do ?
The code used to obtain this graph is the following:
FILE = "data_sensibilite_correlation_phiFR_Tpfr_fusion_ordre"
set contour base
set cntrparam level discrete 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 25, 30, 35, 40, 45, 50, 55, 60
#set cntrparam level incremental 2, 4, 60
set cntrlabel onecolor start 50 interval 10000000
set xrange [-10:10]
set yrange [0.55:0.95]
#set cbrange [0:20]
set style textbox opaque
unset key
set view map
set xlabel "{/Symbol e}_{/Symbol q} [%]"
set ylabel "T_b / T_{c} uncertainties on T_c"
set cblabel "{/Symbol e}_{{/Symbol F} cs} [%]"
set pm3d noborder
splot FILE u 1:2:3 w pm3d, \
FILE u 1:2:3 w l lc "black" nosurface, \
FILE with labels boxed
The data is available here: https://filesender.renater.fr/?s=download&token=c718b69b-1496-47db-9da4-21d48cf08aa4
Some time ago, I experienced the same issue.
Since your data is not accessible anymore, I am creating some test data in the script itself.
The problem is that you see too many labels although you are trying to limit them via
set cntrlabel {start <int>} {interval <int>}.
Let me try to explain: If you plot the contour line into a datablock you will notice that although some contour lines in the graph look like continuous lines, however, in fact, they are interrupted by empty lines in the data.
I guess this comes from the algorithm how gnuplot determines the contour lines. It seems, the more data points you have, the higher the probability that some contour lines are interrupted.
In the first graph below I made the interruptions visible by setting variable line color depending on pseudocolumn -1 (check help pseudocolumns). For the time being ignore the yellow line.
For example, the contour line for the level 8 consists of 5 pieces (i.e. 5 different colors).
This means when plotting the contour labels even if you set every 200 (or interval 10000000) you will get at least as many labels per contour line as many "broken" parts you have for that line.
Test Graph:
So, you could try to merge these interrupted lines which might be feasible, however, is not so easy because:
you have contour lines which should not be merged, e.g. level 15 on the left side and on the right side of the graph
you cannot easily connect the interrupted lines by simply removing the empty lines because the data points of the line parts are not in the right order
A different approach:
Hence, here is another "simple" idea, but not so simple to realize:
Define a parametric curve (yellow line in the above graph) which will intersect all the contour lines which you want to have labeled.
The script will determine the intersection points and will place a label at these positions.
The determination of the intersections is somewhat lengthy and the code is taken from here.
This procedure is certainly slow and not very efficient because it checks each yellow segment against all other segments.
Currently, the sampling of the yellow line needs to be high enough (here: N=21) such that each yellow segment will intersect with one contour line segment. The calculation time for the intersections can probably be shortened considerably if one yellow segment can intersect several contour line segments. Alternatively, the intersection lines could be filtered by level and then intersected. I will try these options asap.
If anyone has a more ideas to improve, please let me know.
Script:
### add contour labels nicely aligned
reset session
# create some test data
f(x,y) = ((4*x)**2 + (-y-5)**2)/10.
set samples 200
set isosamples 200
set table $Data
splot '++' u (x):(y):(f(x,y))
set table $Contours
unset surface
set contour
set cntrparam levels discrete 2,4,6,8,10,15,20,25,30,40
splot $Data u 1:2:3
unset table
set colorsequence classic
set style textbox opaque
set key noautotitle
set view map
# define parametric function for "line of labels"
xmin = -5.5
xmax = 5.5
N = 21
g(x) = 0.25*x**2 - 2
gx(t) = xmin + t*(xmax-xmin)/N
gy(t) = g(gx(t))
set table $LabelLine
plot '+' u (gx($0)):(gy($0)) every ::::N w table
unset table
set xrange [:] noextend
set yrange [:] noextend
# this plotting part can be skipped, it's just for illustration purpose
plot $Contours u 1:2:-1 w l lc var, \
'' u 1:2:3 every 200 w labels boxed, \
$LabelLine u 1:2 w lp pt 7 lc "yellow" noautoscale
pause -1
# some necessary functions
# orientation of 3 points a,b,c: -1=clockwise, 0=linear, +1=counterclockwise
Orientation(a,b,c) = sgn((word(b,1)-word(a,1))*(word(c,2)-word(a,2)) - \
(word(c,1)-word(a,1))*(word(b,2)-word(a,2)))
# check for intersection of segment a-b with segment c-d,
# 0=no intersection, 1=intersection
IntersectionCheck(a,b,c,d) = \
(Orientation(a,c,b)==Orientation(a,d,b)) || (Orientation(c,a,d)==Orientation(c,b,d)) ? 0 : 1
# calculate coordinates of intersection point, "" if identical points
M(a,b) = real(word(a,1)*word(b,2) - word(a,2)*word(b,1))
N(a,b,c,d) = (word(a,1)-word(b,1))*(word(c,2)-word(d,2)) - \
(word(a,2)-word(b,2))*(word(c,1)-word(d,1))
Intersection(a,b,c,d) = N(a,b,c,d) !=0 ? sprintf("%g %g", \
(M(a,b)*(word(c,1)-word(d,1)) - (word(a,1)-word(b,1))*M(c,d))/N(a,b,c,d), \
(M(a,b)*(word(c,2)-word(d,2)) - (word(a,2)-word(b,2))*M(c,d))/N(a,b,c,d)) : ""
# looping data segments for finding intersections
set print $Intersections
do for [i=1:|$LabelLine|-1] {
a = sprintf("%s %s", word($LabelLine[i], 1),word($LabelLine[i], 2))
b = sprintf("%s %s", word($LabelLine[i+1],1),word($LabelLine[i+1],2))
Line = ''
Intersection0 = ''
do for [j=1:|$Contours|-1] {
c = $Contours[j]
d = $Contours[j+1]
if (strlen(c)!=0 && strlen(d)!=0 && c[1:1] ne '#' && c[1:1] ne '#') {
if (IntersectionCheck(a,b,c,d)) {
Intersection1 = Intersection(a,b,c,d)
if ((Intersection0 ne Intersection1)) {
Level = word($Contours[j],3)
print sprintf("%s %s %s",Intersection0, Intersection1, Level)
}
Intersection0 = Intersection1
}
}
else {Intersection0 = ''}
}
}
set print
set palette rgb 33,13,10
plot $Data u 1:2:3 w image, \
$Contours u 1:2 w l lc "black", \
$Intersections u 1:2:3 w labels boxed
### end of script
Result:
Here is a much simpler solution resulting in only one label per level, however, depending on your data you won't know where exactly the labels will be positioned.
The contour lines per level are separated by two empty lines. The different pieces within a contour line of one specific level might be separated into (sub-)blocks separated by a single empty line.
Now, you can address specific rows and sub-blocks via every (check help every). For example, if you only want to plot each second row of each first sub-block you can specify every ::1:0:1:0 (indices are zero-based). You need to play with these numbers, depending on your data and how many contour line breaks you have. However, most likely the labels will not be nicely aligned as in my other (much more complicated) answer. Furthermore, the labeling will be only once per level, i.e. no labels on the left side of the plot in the example below.
Script:
### add contour labels, only one per level
reset session
# create some test data
f(x,y) = ((4*x)**2 + (-y-5)**2)/10.
set samples 200
set isosamples 200
set table $Data
splot '++' u (x):(y):(f(x,y))
set table $Contours
unset surface
set contour
set cntrparam levels discrete 2,4,6,8,10,15,20,25,30,40
splot $Data u 1:2:3
unset table
set colorsequence classic
set style textbox opaque
set key noautotitle
set view map
set xrange [:] noextend
set yrange [:] noextend
set tics out
set palette rgb 33,13,10
plot $Data u 1:2:3 w image, \
$Contours u 1:2 w l lc "black", \
$Contours u 1:2:3 every ::1:1:1:1 w labels boxed
### end of script
Result:
I have a script which takes data (formatted in 3 columns x,y,z) and gives a heat map:
set logscale x 10
set yrange [1e-9:2e-8]
set xlabel "x"
set ylabel "y"
set multiplot
plot 'filetest.dat' u 1:2:9 with image
This is a 2D heat map, shown below:
All I want to do is add contours to this plot, at some z values such as -20 to -8 in in intervals of 2. Unfortunately, none of the answers I've found have been able to help me with this. Any help would be greatly appreciated.
Although there are a lot of examples about contour on www.gnuplot.info, I couldn't find your exact case, because the examples are with functions, not with datablocks or data files (well, it should be similar).
The following code does what you're asking for, but the construct '' u 1:2:3:("") w labels for adding labels still looks strange to me and doesn't allow for plotting boxed labels.
In gnuplot console check help contour and help cntrparam.
Code:
### pm3d with contour lines
reset session
set view equal xyz
# create some test data
set samples 40
set isosamples 40
set table $Data
splot '++' u 1:2:($1*$2/2-9)
unset table
set view map
set contour base
set cntrparam levels incremental -20,2,-8
set cntrlabel font ",10"
set xrange[-5:5]
set yrange[-5:5]
splot $Data u 1:2:3 w pm3d notitle, '' u 1:2:3:("") w labels notitle
### end of code
Result:
Addition:
Here is another approach with plot w image instead of splot w pm3d.
Although still not fully satisfying with the white label boxes on top of the contour lines. Adding an offset to the labels will not work for all labels at the same time. I'm not sure whether there is a way to just interrupt the contour lines for the labels.
Code:
### heatmap with contour lines
reset session
set view equal xyz
# create some test data
set samples 40
set isosamples 40
set table $Data
splot '++' u 1:2:($1*$2/2-9)
unset table
set view map
set contour base
set cntrparam levels incremental -20,2,-8
set cntrlabel font ",10"
set xrange[-5:5]
set yrange[-5:5]
set style textbox noborder opaque
# put contour lines in a separate datablock
unset surface
set table $Contour
splot $Data u 1:2:3
unset table
plot $Data u 1:2:3 w image notitle, \
$Contour u 1:2 w l lw 2 lc "black" not, \
'' u 1:2:3 every 40::3 w labels boxed notitle
### end of code
Result:
Addition 2:
Another variation with colored contour lines and key instead of labels. This seems to be a bit cumbersome, I hope there is a simpler solution for this.
Code:
### heatmap with colored contour lines
reset session
set view equal xyz
# create some test data
set samples 40
set isosamples 40
set table $Data
splot '++' u 1:2:($1*$2/2-9)
unset table
set view map
set contour base
set cntrparam levels incremental -20,2,-8
set xrange[-5:5]
set yrange[-5:5]
set style textbox noborder
# put contour lines in a separate datablock
unset surface
set table $Contour
splot $Data u 1:2:3
unset table
# get contour levels unique and in sorted order
set table $Dummy
plot $Contour u 3 w table
unset table
set table $ContourSorted
plot $Dummy u 1 smooth freq
unset table
print $ContourSorted
set key out right Left
plot $Data u 1:2:3 w image notitle, \
for [i=0:*] $Contour u 1:2:3 index i w l lw 2 lc i+1 not, \
for [i=|$ContourSorted|-2:5:-1] $ContourSorted u (NaN):1 w l lw 2 lc |$ContourSorted|-i-1 ti word($ContourSorted[i],1)
### end of code
Result:
I try to plot two horizontal lines in a coordinate system using GNUPlot. The two lines represent average values in two datasets. Each dataset has the following constants: max, min and average. The same logic is to be applied to both datasets, so we can simply focus at one of them.
The output should be a 800 x 800 PNG image. They share the X axis, but their Y axis is different from each other in terms of the ranges' values and unit of measurement. Naturally, the numerical values of the two lines can vary arbitrarily. More precisely, I need to plot the two lines at, say, y = 300 and y = 500 in pixel coordinates, regardless of the value of average.
As far I as can tell, there is no way to tell GNUPlot to plot something at a specific pixel coordinate. However, I do believe it is possible to to it indirectly by adjusting the ranges to appropriate values. After poking around in GNUPlot, I managed to find proper values. When the proper range values are set, I think the datapoints in the set should be plotted nicely such that they fit into the graph. Now I need a general approach for any values.
I have the following GNUPlot script with arbitrary values for two horizontal lines:
set term png size 800, 800
set multiplot layout 1, 1
# Green line
min_green = 0
max_green = 50
set size 1,1
set ytics 20
set yrange [min_green : max_green]
avg_green = 22
plot avg_green linecolor rgb "green"
# Blue line
min_blue = 10
max_blue = 70
set size 1,1
set ytics 20
set yrange [min_blue : max_blue]
avg_blue = 14
plot avg_blue linecolor rgb "blue"
Use it like this: gnuplot -p script > plot.png
I need two procedure that looks something like this:
range_min = get_new_min_range(pixel_target_y, min, max, avg)
range_max = get_new_max_range(pixel_target_y, min, max, avg)
The ranges is put into set yrange in GNUPlot. The green line must be at y = 500 and the blue line must be at y = 300 (this is the pixel_target_y patameter). Any help is greatly appreciated!
Let me try to repeat in my words if I understood your question correctly:
You want to plot two datasets where the average (or mean) of each datasets have a fixed y-pixel-(or screen) position within the output graph (independent of data values and graph margins), correct?
For this you need the gnuplot variables GPVAL_TERM_YMIN and GPVAL_TERM_YMAX. In order to get these values you have to plot a dummy graph first. Then you need to do some calculations to get the proper range.
As you can see in the result from 3 different plots: the green and blue lines are independent of x-labels or graph titles.
Code:
### have average lines at fixed pixel position within the plot
reset session
myTermSizeX = 800
myTermSizeY = 800
set term pngcairo size myTermSizeX, myTermSizeY
myOutputFile = "Output.png"
set output myOutputFile
myFixY1 = 500
myFixY2 = 300
set title "Some graph title"
set xlabel "x-Axis title"
# create some test data
set table $Data1
plot '+' u 1:(rand(0)*50+40) smooth bezier
unset table
set table $Data2
plot '+' u 1:(rand(0)*40+10) smooth bezier
unset table
stats $Data1 u 2 name 'Data1' nooutput
stats $Data2 u 2 name 'Data2' nooutput
print Data1_min, Data1_mean, Data1_max
print Data2_min, Data2_mean, Data2_max
# dummy plot to get GPVAL_TERM_YMIN, GPVAL_TERM_YMAX
plot x
R_grph1 = real(myFixY1 - GPVAL_TERM_YMIN)/(GPVAL_TERM_YMAX - GPVAL_TERM_YMIN)
R_grph2 = real(myFixY2 - GPVAL_TERM_YMIN)/(GPVAL_TERM_YMAX - GPVAL_TERM_YMIN)
R_data1 = (Data1_mean - Data1_min)/(Data1_max-Data1_min)
R_data2 = (Data2_mean - Data2_min)/(Data2_max-Data2_min)
if (R_data1 > R_grph1) {
Y1min = Data1_min
Y1max = (Data1_mean - Data1_min)/R_grph1 + Data1_min
}
else {
Y1max = Data1_max
Y1min = Data1_max - (Data1_max - Data1_mean)/(1-R_grph1)
}
print Y1min,Y1max
if (R_data2 > R_grph2) {
Y2min = Data2_min
Y2max = (Data2_mean - Data2_min)/R_grph2 + Data2_min}
else {
Y2max = Data2_max
Y2min = Data2_max - (Data2_max - Data2_mean)/(1-R_grph2)
}
print Y2min,Y2max
set yrange [Y1min:Y1max]
set ytics nomirror
set y2range [Y2min:Y2max]
set y2tics nomirror
set output myOutputFile # it seems you have to specify the output again
set key top center
plot \
$Data1 u 1:2 axes x1y1 w lp pt 7 lc rgb "red" ti "Data1", \
Data1_mean axes x1y1 w l lw 2 lc rgb "green" ti "Data1 mean", \
Data1_min axes x1y1 lt 0 not, \
Data1_max axes x1y1 lt 0 not, \
$Data2 u 1:2 axes x1y2 w lp pt 7 lc rgb "orange" ti "Data2", \
Data2_mean axes x1y2 w l lw 2 lc rgb "blue" ti "Data2 mean", \
Data2_min axes x1y2 lt 0 not, \
Data2_max axes x1y2 lt 0 not
set output
### end of code
Result:
I have generated this picture with Gnuplot, shortly by means the flags below for the palette and plot:
set palette defined ( 0 "green", 1 "blue", 2 "blue", 3 "orange" )
plot "10steps_500" u 1:2:3 w p pt 7 ps 2.0 lt pal, "10steps_500-300" u 1:2:3 w p pt 7 ps 2.0 lt pal
However, I wanna bring the blue point to front. Someone knows how can we do it in gnuplot?
You need to first plot the green points, and then the others afterwards. It looks like you get the color information from the third column in your data files, so something like this should work:
plot "10steps_500" u 1:($3 == 0 ? $2 : 1/0):3 w p pt 7 ps 2.0 lt pal, \
"" u 1:($3 != 0 ? $2 : 1/0):3 w p pt 7 ps 2.0 lt pal
This first line plots all the points for which the value in the third column is 0, and the second line plots all the other points.
I am usually using smooth bezier when plotting my data. It makes then easier to understand and also nicer to see. However, I would also like to plot circles, triangles and squares in the right place i.e. where I've got real data. How could I do that?
I'll give an example of what I do:
p "times" u 1:2 w lp smooth bezier title "Time 1", "" u 1:3 w lp smooth bezier title "Time 2"
set xtics("0" 0,"1" 1, "2" 2,"4" 4 ,"8" 8)
getting:
Now I want to set triangles in the green line to the right point corresponding to x=1, x=2,x=4 and x=8. Same for the red line, but instead triangles, circles, for example.
You can just plot the data again without smoothing:
CIRCLEPT = 6
TRIANGLEPT = 9
set xtics("0" 0,"1" 1, "2" 2,"4" 4 ,"8" 8)
plot "times" u 1:2 w lp lt 1 smooth bezier title "Time 1", \
"" u 1:2 w p lt 1 pt CIRCLEPT notitle , \
"" u 1:3 w lp lt 2 smooth bezier title "Time 2", \
"" u 1:3 w p lt 2 pt TRIANGLEPT notitle
As far as getting triangles and circles, you'll need to select the proper point type for your terminal. To figure out which point type to use, you'll need to do something like:
set terminal <whatever>
set output <whatever> #only for non-interactive terminals
test
Now you can look at whatever output was generated by test and along the right side will be a bunch of points of different types. Just pick the type you want (e.g. 7 is often a circle) and put it in the script