[R] ordered matrix question

[Gavin Simpson]

On Tue, 2007-02-27 at 14:46 -0300, Juan Pablo Fededa wrote:
> Hi all,
> 
> Is there an easy way to generate an object wich will be the same matrix, but
> ordered by de cfp value?
> The data frame consists of numeric columns:
> "Block"    "X"    "Y"    "cfp"    "yfp"    "ID"
> 0    524    244    213.41795    7.18482109    1
> 0    556    270    65.383904    9.568372661    2
> 0    528    316    40.789474    5.573732175    3
> 0    642    432    135.81734    12.40134427    4
> 0    716    430    34.359135    3.944923077    5
> 0    894    362    109.63158    3.197160316    6
> 0    958    130    63.98452    3.396452004    7
> 0    506    92    83.513931    9.105496856    8
> 0    476    464    91.674919    9.178089414    9
> 0    364    426    44.13932    2.068334364    10
> 
> Thanks in advance,

Yes, see ?order. E.g.:

mat <- scan()
0    524    244    213.41795    7.18482109    1
0    556    270    65.383904    9.568372661    2
0    528    316    40.789474    5.573732175    3
0    642    432    135.81734    12.40134427    4
0    716    430    34.359135    3.944923077    5
0    894    362    109.63158    3.197160316    6
0    958    130    63.98452    3.396452004    7
0    506    92    83.513931    9.105496856    8
0    476    464    91.674919    9.178089414    9
0    364    426    44.13932    2.068334364    10


mat <- data.frame(matrix(mat, ncol = 6, byrow = TRUE))
names(mat) <- c("Block", "X", "Y", "cfp", "yfp", "ID")
mat
mat[order(mat$cfp), ]

HTH

G
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