Full_Name: Johannes Prix Version: 2.1.1 OS: WinXP, SuSE Linux Submission from: (NULL) (137.208.41.195)
The seq-command produces unnescessary inaccurate results, which can be extremely annoying. I absolutely do not see the nescessity of numerical garbage to appear in the following simple case. E.g. try this: > seq ( 61.55 , 62.00 , by=0.01 ) - round ( seq ( 61.55 , 62.00 , by=0.01 ) , digits=2 ) Output looks like: [1] 0.000000e+00 -7.105427e-15 0.000000e+00 0.000000e+00 -7.105427e-15 -7.105427e-15 0.000000e+00 0.000000e+00 [9] -7.105427e-15 0.000000e+00 0.000000e+00 0.000000e+00 -7.105427e-15 0.000000e+00 0.000000e+00 -7.105427e-15 [17] -7.105427e-15 0.000000e+00 0.000000e+00 -7.105427e-15 0.000000e+00 0.000000e+00 -7.105427e-15 -7.105427e-15 [25] 0.000000e+00 0.000000e+00 -7.105427e-15 0.000000e+00 0.000000e+00 -7.105427e-15 -7.105427e-15 0.000000e+00 [33] 0.000000e+00 -7.105427e-15 0.000000e+00 0.000000e+00 0.000000e+00 -7.105427e-15 0.000000e+00 0.000000e+00 [41] -7.105427e-15 -7.105427e-15 0.000000e+00 0.000000e+00 -7.105427e-15 0.000000e+00 > It is particularly dangerous to use such seq()-contructed lists (without rounding) when e.g. trying to find the first time a given number appears in the list and the number is given without numerical garbage. ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
