Can one add a data.frame to itself? - list

I want to append or add a data.frame to itself...
Much in the same way the one adds:
n <- n + t
I have a function that creates a data.frame.
I have been using:
g <- function(compareA,compareB) {
for (i in 1:1000) {
ttr <- t.test(compareA, compareA, var.equal = TRUE)
tt_pvalues[i] <- ttr$p.value
}
name_tag <- paste(nameA, nameB, sep = "_Vs_")
tt_titles <- data.frame(name_tag, tt_titles)
# character vector which I want to add to a list
ALL_pvalues <- data.frame(tt_pvalues, ALL_pvalues)
# adding a numeric vector of values to a larger data.frame
}
Would cbind be better here?

There are two methods that would "add or append" data to a data.frame by columns and one that would append by rows. Assuming tag is the data.frame, and tt_titles is a vector of the same length that 'tag' has rows, then either of these would work:
tag <- cbind(tag, tt_titles)
# tt_titles could also be a data.frame with same number of rows
Or:
tag[["tt_titles"]] <- tt_titles
Now let's assume that we have instead two data.frames with the same column.names:
bigger.df <- rbind(tag, tag2)

Related

Functions dplyr with rlang::last_error() in purrr::map loop in r

I'm using a function to calculate the length of linestring per cell by ID and store in a list, convert each element of the list into a RasterLayer and turn that list into a RasterStack, average all layers and get a single raster.
#function
# build_length_raster <- function(one_df) {
intersect_list <- by(
one_df ,
one_df$sub_id,
function(subid_df) sf::st_intersection(grid2, subid_df) %>%
dplyr::mutate(length = as.numeric(sf::st_length(.))) %>%
sf::st_drop_geometry()
)
list_length_grid <- purrr::map(intersect_list, function(x)
x %>% dplyr::left_join(x=grid2, by="cell", copy=T) %>%
dplyr::mutate(length=length) %>%
dplyr::mutate_if(is.numeric,coalesce,0)
)
list_length_raster <- purrr::map(list_length_grid, function(x)
raster::rasterize(x, r, field="length", na.rm=F, background=0)
)
list_length_raster2 <- unlist(list_length_raster, recursive=F)
raster_stack <- raster::stack(list_length_raster2)
raster_mean <- raster::stackApply(
raster_stack,
indices = rep(1,nlayers(raster_stack)),
fun = "mean", na.rm = TRUE)
#}
The function presents a step where, in order for the resulting grid of st_intersection() to have the same number of cells as it had initially, I use left_join(by="cell" column).Then I use mutate() to replace the NA's with 0. When I run the function steps for one dataframe from the list, it works perfectly, but when I put it inside map() to do this in a list, I get this error, which seems to refer to the dplyr functions:
final_list <- purrr::map(mylist, build_length_raster)
> rlang::last_error()
<error/rlang_error>
Join columns must be present in data.
x Problem with `cell`.
Backtrace:
1. purrr::map(mylist, build_length_raster)
15. dplyr:::left_join.data.frame(., x = grid, by = "cell", copy = T)
16. dplyr:::join_mutate(...)
17. dplyr:::join_cols(...)
18. dplyr:::standardise_join_by(by, x_names = x_names, y_names = y_names)
19. dplyr:::check_join_vars(by$y, y_names)
Run `rlang::last_trace()` to see the full context.
Is there a way to solved this problem?
MYDATA example
library(tidyverse)
library(sf)
library(purrr)
library(raster)
#data example
id <- c("844", "844", "844", "844", "844","844", "844", "844", "844", "844",
"844", "844", "845", "845", "845", "845", "845","845", "845", "845",
"845","845", "845", "845")
sub_id <- c("2017_844_1", "2017_844_1", "2017_844_1", "2017_844_1", "2017_844_2",
"2017_844_2", "2017_844_2", "2017_844_2", "2017_844_3", "2017_844_3",
"2017_844_3", "2017_844_3", "2017_845_1", "2017_845_1", "2017_845_1",
"2017_845_1", "2017_845_2","2017_845_2", "2017_845_2", "2017_845_2",
"2017_845_3","2017_845_3", "2017_845_3", "2017_845_3")
lat <- c(-30.6456, -29.5648, -27.6667, -31.5587, -30.6934, -29.3147, -23.0538,
-26.5877, -26.6923, -23.40865, -23.1143, -23.28331, -31.6456, -24.5648,
-27.6867, -31.4587, -30.6784, -28.3447, -23.0466, -27.5877, -26.8524,
-23.8855, -24.1143, -23.5874)
long <- c(-50.4879, -49.8715, -51.8716, -50.4456, -50.9842, -51.9787, -41.2343,
-40.2859, -40.19599, -41.64302, -41.58042, -41.55057, -50.4576, -48.8715,
-51.4566, -51.4456, -50.4477, -50.9937, -41.4789, -41.3859, -40.2536,
-41.6502, -40.5442, -41.4057)
df <- tibble(id = as.factor(id), sub_id = as.factor(sub_id), lat, long)
#converting ​to sf
df.sf <- df %>%
​sf::st_as_sf(coords = c("long", "lat"), crs = 4326)
#creating grid
xy <- sf::st_coordinates(df.sf)
grid = sf::st_make_grid(sf::st_bbox(df.sf),
​cellsize = .1, square = FALSE) %>%
​sf::st_as_sf()
#creating raster
r <- raster::raster(grid, res=0.1)
#return grid because raster function changes number of cells
grid2 <- rasterToPolygons(r, na.rm=F) %>%
st_as_sf() %>% mutate(cell=1:ncell(r))
#creating linestring to each sub_id
df.line <- df.sf %>%
dplyr::group_by(sub_id, id) %>%
dplyr::summarize() %>%
sf::st_cast("LINESTRING")
#creating ID list
mylist<- split(df.line, df.line$id)
#separating one dataframe of list to test function
one_df <- df.line[df.line$id=="844",]
one_df$id <- droplevels(one_df$id)
one_df$sub_id <- droplevels(one_df$sub_id)
The specific error is caused because intersect_list has empty items in the list, which cannot be joined because they are empty, and hence have no columns to join by. If you modified the map function to only use non-empty items of intersect_list you would not get that error.
As you noted in the comments, removing the empty list entries with keep(intersect_list, ~ !is.null(.)) before mapping left_join onto the list items will fix the error.
However, I don't think this is the most elegant way to solve this problem. I might misunderstand what the goal is, but if it's to produce a raster from the total length of lines within each grid cell, I think a simpler approach without using purrr might work.
This is not the exact same as your product, but I'm keeping it simpler rn to illustrate an alternate approach. Here is a sum of the lengths in each cell as a stars object (similar to raster but plays better with the tidyverse and sf).
I'm starting off from your objects one_df and grid:
# Turn multiple lines into single MULTILINESTRING:
one_df %>%
st_union() ->
union_df
# Intersection of each grid cell with the MULTILINESTRING geometry:
grid %>%
st_intersection(union_df) ->
grid_lines
# Get lengths:
grid_lines %>%
mutate(length = st_length(x)) %>%
st_drop_geometry() ->
grid_lengths
# Join the calculated lengths back with the spatial grid,
# most of which will have NA for length
grid %>%
left_join(grid_lengths, by = "cell") ->
grid_with_lengths
# Rasterize the length field of the grid
grid_with_lengths %>%
dplyr::select(length) %>%
stars::st_rasterize() ->
length_stars
length_stars %>% mapview::mapview()

Save results for each file of a list of files looping through a factor variable in R. Vector does not update

I am using a list of files, and I am trying to create a data frame that contains: for each sample, the percentage of two particular "GT" types by the levels of another factor variable called "chr" (with 1 to 24 levels).
It would have to look like this:
The problem I keep getting is that the vector never gets updated for the ith sample, it only keeps the first vector created. And then I am not sure how to save that updated vector on my data frame (df).
vector_chr <- vector();
for (i in seq_along(list_files)) {
GT <- list_files[[i]][,9]
chr <- list_files[[i]][,3]
GT$chr <- chr$chr # creating one df with both GT and chr
for (j in unique(GT$chr)){
dat_list = split(GT, GT$chr) # split data frames by chr (1 to 24)
table <- table(dat_list[[j]][,1]) # take GT and make a table
sum <- sum(table[3:4]) # sum GTs 3 and 4
perc <- sum/nrow(GT)
vector_chr <- c(vector_chr,perc) # assign the 24 percentages to a vector
}
df <- data.frame(matrix(ncol = 25, nrow = length(files)))
x <- c("Sample", "chr1", "chr2", "chr3",
"chr4", "chr5", "chr6", "chr7", "chr8", "chr9", "chr10",
"chr11", "chr12","chr13", "chr14", "chr15", "chr16",
"chr17", "chr18", "chr19", "chr20", "chr21", "chr22",
"chrX", "chrXY")
colnames(df) <- x
df$Sample <- names(list_files)
df[i,2:25] <- vector_chr # assign the 24 percentages for EACH sample
}

How to use gsub to remove one string from a line in R?

I have a dat file with data like this:
<Avg. Price>$103
<URL>http://www.tripadvisor.com/ShowUserReviews-g60878-d100506-r21086254-
<Author>expressoparking
etc.
Here's the script I've made to identify each row with an
<Author>
tag, delete that tag, and lastly put the rest of that row into a single column in a data frame.
y <- read.delim("hotel_100506.dat")
author <- grep("<Author>*", y$v1)
data_author <- y[author,]
author2 <- gsub("<Author>", "", author)
dataPractice <- data.frame(data_author)
I know that my data_author variable has the correct data, but the data.frame method doesn't bring any of it over. What's going on here?
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++========================================================================
Okey doke - Here's the solution to putting the author tag line's information in a dataframe:
x <- read.delim("hotel_100505.dat", header = F)
Author <- grep("<Author>", x$V1)
data_Author <- x[Author,]
data_Author2 <- gsub("<Author>","",data_Author)
data <- data.frame(data_Author2)
The OP offers this as the solution, in a comment above:
x <- read.delim("hotel_100505.dat", header = F)
Author <- grep("<Author>", x$V1)
data_Author <- x[Author,]
data_Author2 <- gsub("<Author>","",data_Author)
data <- data.frame(data_Author2)

Function to subset dataframe using pattern list argument

I have a pattern list
patternlist <- list('one' = paste(c('a','b','c'),collapse="|"), 'two' = paste(1:5,collapse="|"), 'three' = paste(c('k','l','m'),collapse="|"))
that I want to select from to extract rows from a data frame
dataframez <- data.frame('letters' = c('a','b','c'), 'numbers' = 1:3, 'otherletters' = c('k','l','m'))
with this function
pattern.record <- function(x, column="letters", value="one")
{
if (column %in% names(x))
{
result <- x[grep(patternlist$value, x$column, ignore.case=T),]
}
else
{
result <- NA
}
return(result)
}
oddly enough, I get an error when I run it:
> pattern.record(dataframez)
Error in grep(patternlist$value, x$column, ignore.case = T) :
invalid 'pattern' argument
The problem is your use of the `$` operator.
In your function, it is looking a column \ named element called column
It is far simpler here to use `[[`
Then x[[column]] uses what column is defined as, not column as a name.
The relevant lines in ?`$` are
Both [[ and $ select a single element of the list. The main difference is that $ does not allow computed indices, whereas [[ does. x$name is equivalent to x[["name", exact = FALSE]]. Also, the partial matching behavior of [[ can be controlled using the exact argument.
You are trying to use value and column as computed indices (i.e. computing what value and column are defined as), thus you need `[[`.
The function becomes
pattern.record <- function(x, column="letters", value="one", pattern_list)
{
if (column %in% names(x))
{
result <- x[grep(pattern_list[[value]], x[[column]], ignore.case=T),]
}
else
{
result <- NA
}
return(result)
}
pattern.record(dataframez, patternlist = pattern_list)
## letters numbers otherletters
## 1 a 1 k
## 2 b 2 l
## 3 c 3 m
note that I've also added an argumentpattern_list so it does not depend on an object named patternlist existing somewhere in the parent environments (in your case the global environment.

Text file to list in R

I have a large text file with a variable number of fields in each row. The first entry in each row corresponds to a biological pathway, and each subsequent entry corresponds to a gene in that pathway. The first few lines might look like this
path1 gene1 gene2
path2 gene3 gene4 gene5 gene6
path3 gene7 gene8 gene9
I need to read this file into R as a list, with each element being a character vector, and the name of each element in the list being the first element on the line, for example:
> pathways <- list(
+ path1=c("gene1","gene2"),
+ path2=c("gene3","gene4","gene5","gene6"),
+ path3=c("gene7","gene8","gene9")
+ )
>
> str(pathways)
List of 3
$ path1: chr [1:2] "gene1" "gene2"
$ path2: chr [1:4] "gene3" "gene4" "gene5" "gene6"
$ path3: chr [1:3] "gene7" "gene8" "gene9"
>
> str(pathways$path1)
chr [1:2] "gene1" "gene2"
>
> print(pathways)
$path1
[1] "gene1" "gene2"
$path2
[1] "gene3" "gene4" "gene5" "gene6"
$path3
[1] "gene7" "gene8" "gene9"
...but I need to do this automatically for thousands of lines. I saw a similar question posted here previously, but I couldn't figure out how to do this from that thread.
Thanks in advance.
Here's one way to do it:
# Read in the data
x <- scan("data.txt", what="", sep="\n")
# Separate elements by one or more whitepace
y <- strsplit(x, "[[:space:]]+")
# Extract the first vector element and set it as the list element name
names(y) <- sapply(y, `[[`, 1)
#names(y) <- sapply(y, function(x) x[[1]]) # same as above
# Remove the first vector element from each list element
y <- lapply(y, `[`, -1)
#y <- lapply(y, function(x) x[-1]) # same as above
One solution is to read the data in via read.table(), but use the fill = TRUE argument to pad the rows with fewer "entries", convert the resulting data frame to a list and then clean up the "empty" elements.
First, read your snippet of data in:
con <- textConnection("path1 gene1 gene2
path2 gene3 gene4 gene5 gene6
path3 gene7 gene8 gene9
")
dat <- read.table(con, fill = TRUE, stringsAsFactors = FALSE)
close(con)
Next we drop the first column, first saving it for the names of the list later
nams <- dat[, 1]
dat <- dat[, -1]
Convert the data frame to a list. Here I just split the data frame on the indices 1,2,...,n where n is the number of rows:
ldat <- split(dat, seq_len(nrow(dat)))
Clean up the empty cells:
ldat <- lapply(ldat, function(x) x[x != ""])
Finally, apply the names
names(ldat) <- nams
Giving:
> ldat
$path1
[1] "gene1" "gene2"
$path2
[1] "gene3" "gene4" "gene5" "gene6"
$path3
[1] "gene7" "gene8" "gene9"
A quick solution based on the linked page...
inlist <- strsplit(readLines("file.txt"), "[[:space:]]+")
pathways <- lapply(inlist, tail, n = -1)
names(pathways) <- lapply(inlist, head, n = 1)
One more solution:
sl <- c("path1 gene1 gene2", "path2 gene1 gene2 gene3") # created by readLines
f <- function(l, s) {
v <- strsplit(s, " ")[[1]]
l[[v[1]]] <- v[2:length(v)]
return(l)
}
res <- Reduce(f, sl, list())