[R language] two /n data merge functions

The two data frames are merged

data1=data.frame(
  names = c('AAA',       'CCC', 'DDD', 'EEE',  'FFF' ),
  logFC = c(3, -0.4, 5, 0.4, -3 ),
  bmi = c(' normal ',        ' normal ',' overweight ',' obesity ',' normal ')
)
data2=data.frame(
  names = c('AAA','BBB',  'CCC', 'DDD', 'EEE'          ),
  gender = c(1, 2, 1, 2, 1),    #1= male  2= Woman 
  bmi = c(' normal ',' Low weight ',' normal ',' overweight ',' obesity '          )
)

merge(data1,data2,all=TRUE)
#  Same result , No need to add by
merge(data1,data2,all=TRUE,by = intersect(names(data1), names(data2)))

names	bmi	logFC	gender
AAA	normal	3	1
BBB	Low weight	NA	2
CCC	normal	-0.4	1
DDD	overweight	5	2
EEE	obesity	0.4	1
FFF	normal	-3	NA

dplyr::full_join Function case

dplyr::full_join(data1,data2)

dplyr::full_join Function case , If added by, There will be The duplicate variable name is .x .y

dplyr::full_join(data1,data2,by=c("names"))

> dplyr::full_join(data1,data2)      
Joining, by = c("names", "bmi")
  names logFC    bmi gender
1   AAA   3.0    normal       1
2   CCC  -0.4    normal       1
3   DDD   5.0    overweight       2
4   EEE   0.4    obesity       1
5   FFF  -3.0    normal      NA
6   BBB    NA  Low weight       2

names	logFC	bmi.x	gender	bmi.y
AAA	3	normal	1	normal
CCC	-0.4	normal	1	normal
DDD	5	overweight	2	overweight
EEE	0.4	obesity	1	obesity
FFF	-3	normal	NA	NA
BBB	NA	NA	2	Low weight

R merge() And dplyr join()

dplyr	base
inner_join(df1, df2)	merge(df1, df2)
left_join(df1, df2)	merge(df1, df2, all.x = TRUE)
right_join(df1, df2)	merge(df1, df2, all.y = TRUE)
full_join(df1, df2)	merge(df1, df2, all = TRUE)
semi_join(df1, df2)	df1[df1$x$x, , drop = FALSE]
anti_join(df1, df2)	df1[!df1$x$x, , drop = FALSE]

#  Assume the same variable , The contents are different , Such as AAA-BMI- often 1
data2=data.frame(
  names = c('AAA','BBB',  'CCC', 'DDD', 'EEE'          ),
  gender = c(1, 2, 1, 2, 1),    #1= male  2= Woman 
  bmi = c(' normal 1',' Low weight ',' normal ',' overweight ',' obesity '          )
)

merge(data1,data2,all=TRUE,by = intersect(names(data1), names(data2)))
#  The result will be a new line 

names	bmi	logFC	gender
AAA	normal	3	NA
AAA	normal 1	NA	1
BBB	Low weight	NA	2
CCC	normal	-0.4	1
DDD	overweight	5	2
EEE	obesity	0.4	1
FFF	normal	-3	NA

Merge multiple data frames

data1=data.frame(
  names = c('AAA',       'CCC', 'DDD', 'EEE',  'FFF' ),
  logFC = c(3, -0.4, 5, 0.4, -3 ),
  bmi = c(' normal ',        ' normal ',' overweight ',' obesity ',' normal ')
)
data2=data.frame(
  names = c('AAA','BBB',  'CCC', 'DDD', 'EEE'          ),
  gender = c(1, 2, 1, 2, 1),    #1= male  2= Woman 
  bmi = c(' normal ',' Low weight ',' normal ',' overweight ',' obesity '          )
)

data3=data.frame(
  names = c('GGG'         ),
  gender = c(" male "),    #1= male  2= Woman 
  bmi = c(' normal '      )
)

file=ls(pattern = "data")
ALL1=list(data1,data2,data3)

multimerge<-function(dat=list(),...){
  if(length(dat)<2)return(as.data.frame(dat))
  mergedat<-dat[[1]]
  dat[[1]]<-NULL
  for(i in dat){
    mergedat<-merge(all=TRUE,mergedat,i,...)
  }
  return(mergedat)
}
multimerge(ALL1)