Goodday, Everyone.
I am writing a classical scientific paper comparing MODIS-retrieved data with ground measured data. I found several papers on this. Almost all of those papers have figures with 1:1 diagonal lines, and I want to draw this with IDL.
First, I tried this with a simple data file. First column is ground- measured air temperature, second column is MODIS-retrieved/processed air temperature.
dat.txt
-4.2 -1.4
0 2.7
2.8 6.9
5.3 4.1
3.8 2.7
5.4 2.9
3.3 1.9
4.6 3
1.6 3.6
5.2 3.2
5.4 5.9
7.9 6.1
4.3 7.8
9.2 6.6
I tried this way.
pro OneOne ; Display 1:1 line
device, decomposed=0, set_font='arial*24*bold'
loadct, 30
window, xsize=700, ysize=700
readcol, 'dat.txt', nws, mod07, format='F, F'
n=n_elements(nws)
vsym, 24
plot, nws, mod07, psym =2, title ='1:1 line - NWS vs MOD07', xtitle = 'NWS', ytitle = 'MOD07', xrange = [-5, 10], yrange = [-5, 10]
end
Now I got a plot with several dots. However, still I don't know how to add the diagonal 1:1 line. Please give me a suggestion. Thanks.
Harry
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