Function meandist() should do this. Its name is kind of hint. Cheers, Jari Oksanen On 16/12/2013, at 21:16 PM, Andres Mellado Diaz wrote:
> Dear list memnbers, > > I would greatly appreciate any suggestion on how to get averaged distance > values (and errors) between groups of samples using vegan (vegdist, dist,...). > > As an example, I have a faunal table (samples by taxa, "mMCINVmmh") and some > grouping factors (for example: "gradreg_mmh") that I want to test, like this: > > >> vegdist(mMCINVmmh, method="bray", binary=FALSE, diag=F, upper=F)->vegdist1 > >> vegdist1 > > TR_1_2 TR_1_3 TR_2_2 TR_2_3 TR_3_1 TR_3_2 > TR_1_3 0.7361704 > TR_2_2 0.1509007 0.7785157 > TR_2_3 0.6465259 0.4095644 0.6832353 > TR_3_1 0.8717468 0.9572968 0.8551546 0.9373980 > TR_3_2 0.6925163 0.7197110 0.7428020 0.4742819 0.7800620 > TR_3_3 0.8166542 0.7199418 0.8365397 0.6215122 0.8582932 0.5364242 > >> gradreg_mmh > > [1] 0 0 3 3 5 5 5 > > Levels: 0 3 5 > >> > > So I want to get the pairwise mean distances and errors between groups 0, 3 > and 5... > > > many thanks in advance, > > Andrés > > -- > Andrés Mellado Díaz > > Centre for Hydrological Studies CEH-CEDEX > Water Quality Department > Pº bajo de la Virgen del Puerto, 3 > 28005, Madrid > SPAIN > > > -- > Andrés Mellado Díaz > > Centre for Hydrological Studies CEH-CEDEX > Water Quality Department > Pº bajo de la Virgen del Puerto, 3 > 28005, Madrid > SPAIN > > _______________________________________________ > R-sig-ecology mailing list > R-sig-ecology@r-project.org > https://stat.ethz.ch/mailman/listinfo/r-sig-ecology _______________________________________________ R-sig-ecology mailing list R-sig-ecology@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-ecology