Hi, I am using 5.0rc2 and am trying to fit a line to a data file with x, y, and x_err columns. I do:
f(x)=m*x+b
fit f(x) 'data.txt' u 1:2:3 xerror via m,b
and gnuplot outputs "xerror requires exactly 2 columns". How can I make this work? Thanks!
Last edit: gnutron 2014-09-23
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Gnuplot does not support fitting [x,y] data with x errors.
The "xerror" keyword was a mistake, and has been removed.
Sorry about that.
The fit command is one of the remaining areas still under revision leading up to version 5. As it stands right now, neither the "xerror" or "noerror" keywords will be used in the final 5.0 release.
If you really mean that the 3rd column contains y errors, that's another story.
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
Ok, good to know. I just made up realistic (small) yerr bars in a fourth column and used the xyerror option. I assume this takes into account both the x- and y-error bars. Thanks!
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
Hi, I am using 5.0rc2 and am trying to fit a line to a data file with x, y, and x_err columns. I do:
f(x)=m*x+b
fit f(x) 'data.txt' u 1:2:3 xerror via m,b
and gnuplot outputs "xerror requires exactly 2 columns". How can I make this work? Thanks!
Last edit: gnutron 2014-09-23
Gnuplot does not support fitting [x,y] data with x errors.
The "xerror" keyword was a mistake, and has been removed.
Sorry about that.
The fit command is one of the remaining areas still under revision leading up to version 5. As it stands right now, neither the "xerror" or "noerror" keywords will be used in the final 5.0 release.
If you really mean that the 3rd column contains y errors, that's another story.
Ok, good to know. I just made up realistic (small) yerr bars in a fourth column and used the xyerror option. I assume this takes into account both the x- and y-error bars. Thanks!