R List of Lists to Data.Frame

R list of lists to data.frame

The value of nrow needs to be fixed. I fixed your code as follows:

dd  <-  as.data.frame(matrix(unlist(listHolder), nrow=length(unlist(listHolder[1]))))

Converting a list of lists into a data.frame in R

What about this?

do <- as.data.frame(do.call(rbind, lapply(my.stuff, as.vector)))
do <- cbind(my.var=rownames(do), do)
do[do == "NULL"] <- NA

Result

> do
   my.var my.col1 my.col2 my.col3 my.col4
AA     AA       1       4      NA      NA
BB     BB      NA      NA      NA      NA
CC     CC      13       8       2      10
DD     DD      NA      NA      -5       7

Edit:

If we don't want lists as column objects as @akrun reasonably suggests, we could do it this way:

u <- as.character(unlist(my.stuff, recursive=FALSE))
u[u == "NULL"] <- NA
do <- matrix(as.integer(u), nrow=4, byrow=TRUE, 
             dimnames=list(NULL, names(my.stuff[[1]])))
do <- data.frame(my.var=names(my.stuff), do, stringsAsFactors=FALSE)

Test:

> all.equal(str(do), str(desired.object))
'data.frame':   4 obs. of  5 variables:
 $ my.var : chr  "AA" "BB" "CC" "DD"
 $ my.col1: int  1 NA 13 NA
 $ my.col2: int  4 NA 8 NA
 $ my.col3: int  NA NA 2 -5
 $ my.col4: int  NA NA 10 7
'data.frame':   4 obs. of  5 variables:
 $ my.var : chr  "AA" "BB" "CC" "DD"
 $ my.col1: int  1 NA 13 NA
 $ my.col2: int  4 NA 8 NA
 $ my.col3: int  NA NA 2 -5
 $ my.col4: int  NA NA 10 7
[1] TRUE

Converting a list of lists to a dataframe in R: The Tidyverse-way

You could use

purrr::map_df(list_of_lists, tibble::as_tibble)

# A tibble: 10 x 3
#      a     b   sum
#   <dbl> <dbl> <dbl>
# 1     1     1     2
# 2     2     3     5
# 3     3     5     8
# 4     4     7    11
# 5     5     9    14
# 6     6    11    17
# 7     7    13    20
# 8     8    15    23
# 9     9    17    26
#10    10    19    29

Make dataframe from list of lists but each element a column

If the names are always a match one-by-one, you can simply do,

do.call(rbind, lapply(myList, unlist))
#     L1 L2 L3 a1 a2 a3 b1 b2 b3
#[1,]  1  2  3  1  2  3  1  2  3
#[2,]  4  5  6  4  5  6  4  5  6
#[3,]  7  8  9  7  8  9  7  8  9

How to convert list of lists to dataframe in R

I couldn't reproduce your example, but what you're trying to do is simple. You could use do.call to call the rbind function on the list and what you get at the end is a pretty dataframe.

list <- getOptionChain("AAPL", "2019/2021")

data <- do.call(rbind, list)

Transforming a list of lists into dataframe

For every list in fruits you can create a one row dataframe and bind the data.

dplyr::bind_rows(lapply(fruits, function(x) as.data.frame(t(sapply(x, 
                 function(y) paste0(y, collapse = "+"))))))

#           V1   V2    V3    V4
#1      orange pear  <NA>  <NA>
#2 pear+orange <NA>  <NA>  <NA>
#3 lemon+apple pear grape apple

extract one element/data frame from a list of lists

So after messing around, the answer seems to be very simple: `results1<-cj1["coefficients",]. This creates the list that I want. Akrun, if you read this, thank you for your support.

Convert a list to a data frame

Update July 2020:

The default for the parameter stringsAsFactors is now default.stringsAsFactors() which in turn yields FALSE as its default.

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Assuming your list of lists is called l:

df <- data.frame(matrix(unlist(l), nrow=length(l), byrow=TRUE))

The above will convert all character columns to factors, to avoid this you can add a parameter to the data.frame() call:

df <- data.frame(matrix(unlist(l), nrow=132, byrow=TRUE),stringsAsFactors=FALSE)

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