[R] merge multiple data frames
Massimo Bressan
mbressan at arpa.veneto.it
Mon Jan 30 13:47:10 CET 2012
thanks michael
it's working like a charm: that's exaclty what I was looking for
bye
max
----- Original Message -----
From: "R. Michael Weylandt" <michael.weylandt at gmail.com>
To: "Massimo Bressan" <mbressan at arpa.veneto.it>
Cc: <r-help at r-project.org>
Sent: Friday, January 27, 2012 4:16 PM
Subject: Re: [R] merge multiple data frames
Oh, sorry -- I assumed that was intentional since my code passed the
identical() test with what you said you wanted.
Perhaps this gets what you meant you wanted instead (though the
treatment of the names is far from elegant)
mergeAll <- function(..., by = "date", all = TRUE) {
dotArgs <- list(...)
dotNames <- lapply(dotArgs, names)
repNames <- Reduce(intersect, dotNames)
repNames <- repNames[repNames != by]
for(i in seq_along(dotArgs)){
wn <- which( (names(dotArgs[[i]]) %in% repNames) &
(names(dotArgs[[i]]) != by))
names(dotArgs[[i]])[wn] <- paste(names(dotArgs[[i]])[wn],
names(dotArgs)[[i]], sep = ".")
}
Reduce(function(x, y) merge(x, y, by = by, all = all), dotArgs)
}
print(str(mergeAll(a=a,b=b,c=c)))
Is that what you were going for?
Michael
On Fri, Jan 27, 2012 at 3:19 AM, Massimo Bressan
<mbressan at arpa.veneto.it> wrote:
> I tested your code: it's OK but there is still the problem of the suffixes
> for the last dataframe....
> thank you for the support
>
>
> ----- Original Message ----- From: "R. Michael Weylandt"
> <michael.weylandt at gmail.com>
> To: "maxbre" <mbressan at arpa.veneto.it>
> Cc: <r-help at r-project.org>
> Sent: Thursday, January 26, 2012 8:19 PM
> Subject: Re: [R] merge multiple data frames
>
>
> I might do something like this:
>
> mergeAll <- function(..., by = "date", all = TRUE) {
> dotArgs <- list(...)
> Reduce(function(x, y)
> merge(x, y, by = by, all = all, suffixes=paste(".", names(dotArgs),
> sep = "")),
> dotArgs)}
>
> mergeAll(a = a, b = b, c = c)
>
> str(.Last.value)
>
> You also might be able to set it up to capture names without you
> having to put "a = a" etc. using substitute.
>
> On Thu, Jan 26, 2012 at 12:29 PM, maxbre <mbressan at arpa.veneto.it> wrote:
>>
>> This is my reproducible example (three data frames: a, b, c)
>>
>> a<-structure(list(date = structure(1:6, .Label = c("2012-01-03",
>> "2012-01-04", "2012-01-05", "2012-01-06", "2012-01-07", "2012-01-08",
>> "2012-01-09", "2012-01-10", "2012-01-11", "2012-01-12", "2012-01-13",
>> "2012-01-14", "2012-01-15", "2012-01-16", "2012-01-17", "2012-01-18",
>> "2012-01-19", "2012-01-20", "2012-01-21", "2012-01-22", "2012-01-23"
>> ), class = "factor"), so2 = c(0.799401398190476, 0, 0,
>> 0.0100453950434783,
>> 0.200154920565217, 0.473866969181818), nox = c(111.716109973913,
>> 178.077239330435, 191.257829021739, 50.6799951473913, 115.284643540435,
>> 110.425185027727), no = c(48.8543691516522, 88.7197448817391,
>> 93.9931932472609, 13.9759949817391, 43.1395266865217, 41.7280296016364
>> ), no2 = c(36.8673432865217, 42.37150668, 47.53311701, 29.3026882474783,
>> 49.2986070321739, 46.5978461731818), co = c(0.618856168125,
>> 0.996593475083333,
>> 0.666987416083333, 0.383437311166667, 0.281604928875, 0.155383408913043
>> ), o3 = c(12.1393100029167, 12.3522739816522, 10.9908791203043,
>> 26.9122200013043, 13.8421695947826, 12.3788847045455), ipa =
>> c(167.541954974667,
>> 252.7196257875, 231.802370709167, 83.4850259595833, 174.394613581667,
>> 173.868599272609), ws = c(1.47191016429167, 0.765781205208333,
>> 0.937053086791667, 1.581022406625, 0.909756802125, 0.959252831695652
>> ), wd = c(45.2650019737732, 28.2493544114369, 171.049080544214,
>> 319.753674830936, 33.8713897347193, 228.368119533759), temp =
>> c(7.91972825883333,
>> 3.79434291520833, 2.1287644735, 6.733854600625, 3.136579722,
>> 3.09864120704348), umr = c(86.11566638875, 94.5034087491667,
>> 94.14451249375, 53.1016709004167, 65.63420423, 74.955669236087
>> )), .Names = c("date", "so2", "nox", "no", "no2", "co", "o3",
>> "ipa", "ws", "wd", "temp", "umr"), row.names = c(NA, 6L), class =
>> "data.frame")
>>
>>
>> b<-structure(list(date = structure(1:6, .Label = c("2012-01-03",
>> "2012-01-04", "2012-01-05", "2012-01-06", "2012-01-07", "2012-01-08",
>> "2012-01-09", "2012-01-10", "2012-01-11", "2012-01-12", "2012-01-13",
>> "2012-01-14", "2012-01-15", "2012-01-16", "2012-01-17", "2012-01-18",
>> "2012-01-19", "2012-01-20", "2012-01-21", "2012-01-22", "2012-01-23"
>> ), class = "factor"), so2 = c(0, 0, 0, 0, 0, 0), nox = c(13.74758511,
>> 105.8060582, 61.22720599, 11.45280354, 56.86804174, 39.17917222
>> ), no = c(0.882593766, 48.97037506, 9.732937217, 1.794549972,
>> 16.32300019, 8.883637786), no2 = c(11.80447753, 25.35235381,
>> 28.72990261, 8.590004034, 31.9003796, 25.50512403), co = c(0.113954917,
>> 0.305985964, 0.064001839, 0, 1.86e-05, 0), o3 = c(5.570499897,
>> 9.802379608, 5.729360104, 11.91304016, 12.13407993, 10.00961971
>> ), ipa = c(6.065110207, 116.9079971, 93.21240234, 10.5777998,
>> 66.40740204, 34.47359848), ws = c(0.122115001, 0.367668003, 0.494913995,
>> 0.627124012, 0.473895013, 0.593913019), wd = c(238.485119317031,
>> 221.645073036776, 220.372076815032, 237.868340917096, 209.532933617465,
>> 215.752030286564), temp = c(4.044159889, 1.176810026, 0.142934993,
>> 0.184606999, -0.935989976, -2.015399933), umr = c(72.29229736,
>> 88.69879913, 87.49530029, 24.00079918, 44.8852005, 49.47729874
>> )), .Names = c("date", "so2", "nox", "no", "no2", "co", "o3",
>> "ipa", "ws", "wd", "temp", "umr"), row.names = c(NA, 6L), class =
>> "data.frame")
>>
>>
>> c<-structure(list(date = structure(1:6, .Label = c("2012-01-03",
>> "2012-01-04", "2012-01-05", "2012-01-06", "2012-01-07", "2012-01-08",
>> "2012-01-09", "2012-01-10", "2012-01-11", "2012-01-12", "2012-01-13",
>> "2012-01-14", "2012-01-15", "2012-01-16", "2012-01-17", "2012-01-18",
>> "2012-01-19", "2012-01-20", "2012-01-21", "2012-01-22", "2012-01-23"
>> ), class = "factor"), so2 = c(2.617839247, 0, 0, 0.231044086,
>> 0.944608887, 2.12400444), nox = c(308.9046313, 275.6778849, 390.0824142,
>> 178.7429364, 238.655832, 251.892601), no = c(156.0262489, 151.4412498,
>> 221.0725021, 65.96049786, 106.541748, 119.3471241), no2 = c(74.80145447,
>> 59.29991481, 66.5897975, 77.84267978, 75.68422569, 85.43044816
>> ), co = c(1.628431197, 1.716231492, 1.264678366, 1.693460745,
>> 0.780637084, 0.892724398), o3 = c(26.1473999, 15.91584015, 22.46199989,
>> 37.39400101, 15.63426018, 17.51494026), ipa = c(538.414978, 406.4620056,
>> 432.6459961, 275.2820129, 435.7909851, 436.8039856), ws = c(4.995530128,
>> 1.355309963, 1.708899975, 3.131690025, 1.546270013, 1.571320057
>> ), wd = c(58.15639877, 64.5657153143848, 39.9754269501381,
>> 24.0739884380921,
>> 55.9453098437477, 56.7648829092446), temp = c(10.24740028, 7.052690029,
>> 4.33258009, 13.91609955, 8.762220383, 11.04300022), umr = c(97.60900116,
>> 96.91899872, 96.20649719, 94.74620056, 82.04550171, 89.41320038
>> )), .Names = c("date", "so2", "nox", "no", "no2", "co", "o3",
>> "ipa", "ws", "wd", "temp", "umr"), row.names = c(NA, 6L), class =
>> "data.frame")
>>
>>
>> Given the three data frames “a”, “b” and “c”, I need to merge them all by
>> the common field “date”.
>> The following attempt is working fine but…
>>
>> # code start
>> all<-merge(a,b,by="date",suffixes=c(".a",".b"),all=T)
>> all<-merge(all,c,by="date",all=T)
>> # code end
>>
>> …I would like to possibly do it in just “one shot” (a generalisation of
>> the
>> code for a more complex case of handling many data frames) also by
>> assigning
>> proper suffixes to each variable (not possible with the previous code
>> snippet)
>>
>> Then I also try a different approach with the use of the library reshape
>> and
>> the function “merge_all” but…
>>
>> # code start
>> library("reshape")
>> all.new<-merge_all(a, b, c, by="date", all=T, suffixes=c(".a",".b",".c"))
>> # code end
>>
>> …I got the following error message:
>> error in merge in merge.data.frame(as.data.frame(x), as.data.frame(y),
>> ...)
>> :
>> formal argument "all" associated to different argument passed
>> (a free translation from italian)
>>
>> My question is:
>> how to accomplish the merging of multiple data frames with all the same
>> variable names and by a single id field with the need of “keeping track”
>> of
>> the original data frame by means of the use of suffixes appended to new
>> variables?
>>
>> Any help much appreciated
>>
>> Thank you
>>
>>
>>
>>
>> --
>> View this message in context:
>> http://r.789695.n4.nabble.com/merge-multiple-data-frames-tp4331089p4331089.html
>>
>> Sent from the R help mailing list archive at Nabble.com.
>>
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