How to Name the "Row Names" Column in R

How do I name the row names column in r

It sounds like you want to convert the rownames to a proper column of the data.frame. eg:

# add the rownames as a proper column
myDF <- cbind(Row.Names = rownames(myDF), myDF)
myDF

#           Row.Names id val vr2
# row_one     row_one  A   1  23
# row_two     row_two  A   2  24
# row_three row_three  B   3  25
# row_four   row_four  C   4  26

If you want to then remove the original rownames:

rownames(myDF) <- NULL
myDF
#   Row.Names id val vr2
# 1   row_one  A   1  23
# 2   row_two  A   2  24
# 3 row_three  B   3  25
# 4  row_four  C   4  26

Alternatively, if all of your data is of the same class (ie, all numeric, or all string), you can convert to Matrix and name the dimnames

myMat <- as.matrix(myDF)
names(dimnames(myMat)) <- c("Names.of.Rows", "")
myMat

# Names.of.Rows id  val vr2 
#   row_one   "A" "1" "23"
#   row_two   "A" "2" "24"
#   row_three "B" "3" "25"
#   row_four  "C" "4" "26"

Putting row names and column names when converting from list to data frame

In LWfunction return a 1-row dataframe with all the required values in it.

library(FSA)
library(FSAdata)
library(dplyr)
library(tidyr)

LWfunction <- function(x) {
  fits <- lm(log(weight) ~ log(length), data = x)
  a <- hoCoef(fits, 2,3)
  b <- confint(fits)
  output <- cbind(a, data.frame(intercept_2.5 = b[1, 1],
                                intercept_97.5 = b[1, 2], 
                                log_length_2.5 = b[2, 1], 
                                log_length_97.5 = b[2, 2]))
  return(output)
}

apply it for each year and month :

result <- data %>%
            group_by(month, year) %>%
            summarise(output = list(LWfunction(cur_data()))) %>%
            ungroup %>%
            unnest(output)

result
# A tibble: 7 x 13
#  month  year  term `Ho Value` Estimate `Std. Error`       T    df
#  <int> <int> <dbl>      <dbl>    <dbl>        <dbl>   <dbl> <dbl>
#1     4  1992     2          3     3.00       0.0396  0.0216    58
#2     5  1992     2          3     2.88       0.0315 -3.78      64
#3     6  1992     2          3     2.86       0.0317 -4.43     152
#4     7  1992     2          3     2.87       0.0189 -7.11     147
#5     8  1992     2          3     2.89       0.0312 -3.40      67
#6     9  1992     2          3     3.02       0.0326  0.680    114
#7    10  1992     2          3     3.00       0.0314 -0.113     64
# … with 5 more variables: `p value` <dbl>, intercept_2.5 <dbl>,
#   intercept_97.5 <dbl>, log_length_2.5 <dbl>,
#   log_length_97.5 <dbl>

Is there a way to name column names or rownames?

To construct an array with named dimnames, pass a named list as the dimnames argument of matrix or array:

x <- array(seq_len(18L), dim = c(3L, 3L, 2L),
           dimnames = list(D1 = letters[1:3], D2 = letters[4:6], D3 = letters[7:8]))
x
## , , D3 = g
## 
##    D2
## D1  d e f
##   a 1 4 7
##   b 2 5 8
##   c 3 6 9
## 
## , , D3 = h
## 
##    D2
## D1   d  e  f
##   a 10 13 16
##   b 11 14 17
##   c 12 15 18

To modify an existing array so that it has named dimnames, set the names attribute of the dimnames attribute:

y <- array(seq_len(18L), dim = c(3L, 3L, 2L),
           dimnames = list(letters[1:3], letters[4:6], letters[7:8]))
names(dimnames(y)) <- c("D1", "D2", "D3")

identical(x, y)
## [1] TRUE

However, note that names(dimnames(y)) <- value will not work if dimnames(y) is NULL:

z <- array(seq_len(18L), dim = c(3L, 3L, 2L))
names(dimnames(z)) <- c("D1", "D2", "D3")
## Error in names(dimnames(z)) <- c("D1", "D2", "D3") : 
##   attempt to set an attribute on NULL

To get named but "empty" dimnames in the above case, you would have to do something like

dimnames(z) <- list(D1 = NULL, D2 = NULL, D3 = NULL)

or equivalently

dimnames(z) <- setNames(vector("list", 3L), c("D1", "D2", "D3"))

Now:

z
## , , 1
## 
##       D2
## D1     [,1] [,2] [,3]
##   [1,]    1    4    7
##   [2,]    2    5    8
##   [3,]    3    6    9
## 
## , , 2
## 
##       D2
## D1     [,1] [,2] [,3]
##   [1,]   10   13   16
##   [2,]   11   14   17
##   [3,]   12   15   18

It is interesting that we don't see D3 = 1 and D3 = 2 in the print output. That might be a bug - I'd have to ask the people upstairs.

Convert row names into first column

Or you can use tibble's rownames_to_column which does the same thing as David's answer:

library(tibble)
df <- tibble::rownames_to_column(df, "VALUE")

Note: The earlier function called add_rownames() has been deprecated and is being replaced by tibble::rownames_to_column()

Get the column name and row name of a specific value in a dataframe

You may use which with arr.ind = TRUE to get row and column number where 5 is present. This can be changed to row and column names.

mat <- which(df == 5, arr.ind = TRUE)
paste('row : ', rownames(df)[mat[, 1]], 'column :', colnames(df)[mat[, 2]])
#[1] "row :  200 column : b"

get value using rowname and column name in R?

It is not a row name attribute, but a column 'A' So, create a logical index with the 'A' column, use that as row index, while specifying the column as the 'columnName'

df[df$A == 'row Name 1', 'columnName']

R: count times per column a condition is met and row names appear in a list

We may do this with rowwise

library(dplyr)
df2 %>% 
   rowwise %>%
    mutate(x = +(sum(df1[[rownames]][df1$rownames %in% x]) >= 5), 
           y = +(sum(df1[[rownames]][df1$rownames %in% y]) >= 5)) %>%
    ungroup

-output

# A tibble: 3 × 5
  rownames batch totalcount     x     y
  <chr>    <chr>      <int> <int> <int>
1 sample1  a             10     1     0
2 sample2  b             15     1     1
3 sample3  a              6     0     1

Or based on the data, a base R option would be

out <- aggregate(. ~ grp, FUN = sum, 
     transform(df1,  grp = c('x', 'y')[1 + (rownames %in% y)] )[-1])
df2[out$grp] <- +(t(out[-1]) >= 5)