Related
Year A B C D E F
1993-Q1 15.3 5.77 437.02 487.68 97 86.9
1993-Q2 13.5 5.74 455.2 504.5 94.7 85.4
1993-Q3 12.9 5.79 469.42 523.37 92.4 82.9
:::
2021-Q1 18.3 6.48 35680.82 29495.92 182.2 220.4
2021-Q2 7.9 6.46 36940.3 30562.03 180.4 218
Dataset1 <- read.csv('C:/Users/s/Desktop/R/intro/data/Dataset1.csv')
class(Dataset1)
[1] "data.frame"
time_series <- ts(Dataset1, start=1993, frequency = 4)
class(time_series)
[1] "mts" "ts" "matrix"
I don't know how to proceed from there to read my Year column as dates (quaterly) instead of numbers!
Date class does not work well with ts class. It is better to use year and quarter. Using the input shown reproducibly in the Note at the end use read.csv.zoo with yearqtr class and then convert it to ts. The strip.white is probably not needed but we added it just in case.
library(zoo)
z <- read.csv.zoo("Dataset1.csv", FUN = as.yearqtr, format = "%Y-Q%q",
strip.white = TRUE)
tt <- as.ts(z)
tt
## A B C D E F
## 1993 Q1 15.3 5.77 437.02 487.68 97.0 86.9
## 1993 Q2 13.5 5.74 455.20 504.50 94.7 85.4
## 1993 Q3 12.9 5.79 469.42 523.37 92.4 82.9
class(tt)
## [1] "mts" "ts" "matrix"
as.integer(time(tt)) # years
## [1] 1993 1993 1993
cycle(tt) # quarters
## Qtr1 Qtr2 Qtr3
## 1993 1 2 3
as.numeric(time(tt)) # time in years
## [1] 1993.00 1993.25 1993.50
If you did want to use Date class it would be better to use a zoo (or xts) series.
zd <- aggregate(z, as.Date, c)
zd
## A B C D E F
## 1993-01-01 15.3 5.77 437.02 487.68 97.0 86.9
## 1993-04-01 13.5 5.74 455.20 504.50 94.7 85.4
## 1993-07-01 12.9 5.79 469.42 523.37 92.4 82.9
If you want a data frame or xts object then fortify.zoo(z), fortify.zoo(zd), as.xts(z) or as.xts(zd) can be used depending on which one you want.
Note
Lines <- "Year,A,B,C,D,E,F
1993-Q1,15.3,5.77,437.02,487.68,97,86.9
1993-Q2,13.5,5.74,455.2,504.5,94.7,85.4
1993-Q3,12.9,5.79,469.42,523.37,92.4,82.9
"
cat(Lines, file = "Dataset1.csv")
lubridate has really nice year-quarter function yq to convert year quarters to dates.
Dataset1<-structure(list(Year = c("1993-Q1", "1993-Q2", "1993-Q3", "1993-Q4", "1994-Q1", "1994-Q2"), ChinaGDP = c(15.3, 13.5, 12.9, 14.1, 14.1, 13.3), Yuan = c(5.77, 5.74, 5.79, 5.81, 8.72, 8.7), totalcredit = c(437.02, 455.2, 469.42, 521.68, 363.42, 389.01), bankcredit = c(487.68, 504.5, 523.37, 581.83, 403.48, 431.06), creditpercGDP = c(97, 94.7, 92.4, 95.6, 91.9, 90), creditGDPratio = c(86.9, 85.4, 82.9, 85.7, 82.8, 81.2)), row.names = c(NA, 6L), class = "data.frame")
library(lubridate)
library(dplyr)
df_quarter <- Dataset1 %>%
mutate(date=yq(Year)) %>%
relocate(date, .after=Year)
df_quarter
#> Year date ChinaGDP Yuan totalcredit bankcredit creditpercGDP
#> 1 1993-Q1 1993-01-01 15.3 5.77 437.02 487.68 97.0
#> 2 1993-Q2 1993-04-01 13.5 5.74 455.20 504.50 94.7
#> 3 1993-Q3 1993-07-01 12.9 5.79 469.42 523.37 92.4
#> 4 1993-Q4 1993-10-01 14.1 5.81 521.68 581.83 95.6
#> 5 1994-Q1 1994-01-01 14.1 8.72 363.42 403.48 91.9
#> 6 1994-Q2 1994-04-01 13.3 8.70 389.01 431.06 90.0
#> creditGDPratio
#> 1 86.9
#> 2 85.4
#> 3 82.9
#> 4 85.7
#> 5 82.8
#> 6 81.2
Created on 2022-01-15 by the reprex package (v2.0.1)
I have the following dataset of weather conditions in 5 different sites observed in 15-minute intervals over a year, and am developing a shiny app based on it.
site_id date_time latitude longitude ambient_air_tem~ relative_humidy barometric_pres~ average_wind_sp~ particulate_den~
<chr> <dttm> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
1 arc1046 2019-11-15 09:15:00 -37.8 145. 14.4 65.4 1007. 7.45 3.9
2 arc1048 2019-11-15 09:15:00 -37.8 145. 14.0 65.5 1006. 6.95 4.4
3 arc1045 2019-11-15 09:15:00 -37.8 145. 14.8 60 1007. 4.93 3.9
4 arc1047 2019-11-15 09:15:00 -37.8 145. 14.4 66.1 1008. 7.85 4.5
5 arc1050 2019-11-15 09:15:00 -37.8 145. 14.1 64.7 1007. 5.8 3.9
6 arc1045 2019-11-15 09:30:00 -37.8 145. 15.4 57.1 1007. 4.43 3.8
7 arc1046 2019-11-15 09:30:00 -37.8 145. 14.8 63.2 1007. 7.6 4.5
8 arc1047 2019-11-15 09:30:00 -37.8 145. 15.2 62.7 1008 7.13 3.6
9 arc1048 2019-11-15 09:30:00 -37.8 145. 14.6 62.2 1007. 7.09 4.7
10 arc1050 2019-11-15 09:30:00 -37.8 145. 14.6 62.5 1007 5.94 3.5
I mapped the 5 sites using leaflet.
leaflet(quarter_hour_readings) %>%
addTiles() %>%
addCircleMarkers(
layerId = ~site_id,
label = ~site_id)
And now want to include radial(spider) plots on each of the markers on the map, upon selecting a single date. For now I have filtered out the data values at a single date, for the following radial plot.
library(fmsb)
dat <- rbind(c(85.00,100.00,2000.00,160.00,999.9,1999.9),
c(-40.00,0.00,10.00,0.00,0.00,0.00),
quarter_hour_readings %>%
filter(date_time == as.POSIXct("2019-11-15 09:15:00",tz="UTC")) %>%
column_to_rownames(var="site_id") %>%
select(c("ambient_air_temperature","relative_humidy","barometric_pressure", "average_wind_speed", "particulate_density_2.5", "particulate_density_10")))
radarchart(dat)
I am however unsure how to include these raidal plots on the respective markers on the map and if there was an easier way to handle this. Although I found this package to insert minicharts on leaflet maps, I wasn't able to find how to add radar plots on a map.
Note. Since you did not provide a reproducible dataset, I take some fake data.
You can follow the approach described here:
m <- leaflet() %>% addTiles()
rand_lng <- function(n = 5) rnorm(n, -93.65, .01)
rand_lat <- function(n = 5) rnorm(n, 42.0285, .01)
rdr_dat <- structure(list(total = c(5, 1, 2.15031008049846, 4.15322054177523,
2.6359076872468),
phys = c(15, 3, 12.3804132539814, 6.6208886719424,
12.4789917719968),
psycho = c(3, 0, 0.5, NA, 3),
social = c(5, 1, 2.82645894121379,
4.82733338139951, 2.81333662476391),
env = c(5, 1, 5, 2.5, 4)),
row.names = c(NA, -5L), class = "data.frame")
makePlotURI <- function(expr, width, height, ...) {
pngFile <- plotPNG(function() { expr }, width = width, height = height, ...)
on.exit(unlink(pngFile))
base64 <- httpuv::rawToBase64(readBin(pngFile, raw(1), file.size(pngFile)))
paste0("data:image/png;base64,", base64)
}
set.seed(1)
plots <- data.frame(lat = rand_lat(),
lng = rand_lng(),
radar = rep(makePlotURI({radarchart(rdr_dat)}, 200, 200, bg = "white"), 5))
m %>% addMarkers(icon = ~ icons(radar), data = plots)
I have some climate data with temperature and humidity as well as a timestamp which is transformed to the time in %H:%M.
When using ggplot2 for visualization, the time gets sorted - screwing the order of measurements as the first measurement was taken at 14:00 (2pm) and the last one at 10:27 (10:27am) the following day.
How do I prevent ggplot2 from sorting the x-values? (see plot)
MVE:
library(tidyverse)
df = read_csv('./climate_stats_incl_time.csv')
colnames(df)[1] <- c('sample')
head(df)
tail(df)
ggplot(data=df, mapping=aes(x=time)) +
geom_line(aes(y=temperature, color='red')) +
geom_line(aes(y=humidity, color='blue'))
> head(df)
# A tibble: 6 x 5
sample timestamp temperature humidity time
<dbl> <dbl> <dbl> <dbl> <drtn>
1 0 1581253210. 21.9 47.6 14:00
2 1 1581253275. 21.7 47.8 14:01
3 2 1581253336. 21.7 47.8 14:02
4 3 1581253397. 21.8 47.8 14:03
5 4 1581253457. 21.7 47.8 14:04
6 5 1581253520. 21.8 47.8 14:05
> tail(df)
# A tibble: 6 x 5
sample timestamp temperature humidity time
<dbl> <dbl> <dbl> <dbl> <drtn>
1 1203 1581326567. 19.1 49.8 10:22
2 1204 1581326628. 19.1 49.7 10:23
3 1205 1581326688. 19.1 49.9 10:24
4 1206 1581326749. 19.1 49.9 10:25
5 1207 1581326812. 19.1 49.7 10:26
6 1208 1581326873. 19.1 49.8 10:27
Format your timestamps to a proper date-time (assuming the origin is 1970):
df$date_time <- as.POSIXct(df$timestamp, origin="1970-01-01", tz = "GMT")
Then use this new date_time variable instead of time for plotting
Edit:
I accidentally submitted a wrong solution (I re-formated the date-time to a date) . Now the solution should work for your problem (i.e. it makes a date-time!)
A workaround
df %>%
mutate(orig_seq = seq(1,nrow(df),1)) %>%
ggplot(mapping=aes(x=reorder(time, orig_seq)) +
geom_line(aes(y=temperature, color='red')) +
geom_line(aes(y=humidity, color='blue'))
Here's the tweak to my previously posted question. Here's my data:
set.seed(3737)
DF2 = data.frame(user_id = c(rep(27, 7), rep(11, 7)),
date = as.Date(rep(c('2016-01-01', '2016-01-03', '2016-01-05', '2016-01-07', '2016-01-10', '2016-01-14', '2016-01-16'), 2)),
value = round(rnorm(14, 15, 5), 1))
user_id date value
27 2016-01-01 15.0
27 2016-01-03 22.4
27 2016-01-05 13.3
27 2016-01-07 21.9
27 2016-01-10 20.6
27 2016-01-14 18.6
27 2016-01-16 16.4
11 2016-01-01 6.8
11 2016-01-03 21.3
11 2016-01-05 19.8
11 2016-01-07 22.0
11 2016-01-10 19.4
11 2016-01-14 17.5
11 2016-01-16 19.3
This time, I'd like to calculate cumulative sum of a value for each user_id for the specified time period'; e.g. last 7, 14 days. The desirable solution would look like this:
user_id date value v_minus7 v_minus14
27 2016-01-01 15.0 15.0 15.0
27 2016-01-03 22.4 37.4 37.4
27 2016-01-05 13.3 50.7 50.7
27 2016-01-07 21.9 72.6 72.6
27 2016-01-10 20.6 78.2 93.2
27 2016-01-14 18.6 61.1 111.8
27 2016-01-16 16.4 55.6 113.2
11 2016-01-01 6.8 6.8 6.8
11 2016-01-03 21.3 28.1 28.1
11 2016-01-05 19.8 47.9 47.9
11 2016-01-07 22.0 69.9 69.9
11 2016-01-10 19.4 82.5 89.3
11 2016-01-14 17.5 58.9 106.8
11 2016-01-16 19.3 56.2 119.3
Ideally, I'd like to use dplyr for this, but other packages would be fine.
logic : first group by user_id, followed by date. Now for each subset of data, we are checking which all dates lie between the current date and 7/14 days back using between() which returns a logical vector.
Based on this logical vector I add the value column
library(data.table)
setDT(DF2)[, `:=`(v_minus7 = sum(DF2$value[DF2$user_id == user_id][between(DF2$date[DF2$user_id == user_id], date-7, date, incbounds = TRUE)]),
v_minus14 = sum(DF2$value[DF2$user_id == user_id][between(DF2$date[DF2$user_id == user_id], date-14, date, incbounds = TRUE)])),
by = c("user_id", "date")][]
# user_id date value v_minus7 v_minus14
#1: 27 2016-01-01 15.0 15.0 15.0
#2: 27 2016-01-03 22.4 37.4 37.4
#3: 27 2016-01-05 13.3 50.7 50.7
#4: 27 2016-01-07 21.9 72.6 72.6
#5: 27 2016-01-10 20.6 78.2 93.2
#6: 27 2016-01-14 18.6 61.1 111.8
#7: 27 2016-01-16 16.4 55.6 113.2
#8: 11 2016-01-01 6.8 6.8 6.8
#9: 11 2016-01-03 21.3 28.1 28.1
#10: 11 2016-01-05 19.8 47.9 47.9
#11: 11 2016-01-07 22.0 69.9 69.9
#12: 11 2016-01-10 19.4 82.5 89.3
#13: 11 2016-01-14 17.5 58.9 106.8
#14: 11 2016-01-16 19.3 56.2 119.3
# from alexis_laz answer.
ff = function(date, value, minus){
cs = cumsum(value)
i = findInterval(date - minus, date, rightmost.closed = TRUE)
w = which(as.logical(i))
i[w] = cs[i[w]]
cs - i
}
setDT(DF2)
DF2[, `:=`( v_minus7 = ff(date, value, 7),
v_minus14 = ff(date, value, 14)), by = c("user_id")]
You can use rollapply from zoo once you fill out the missing dates first:
library(dplyr)
library(zoo)
set.seed(3737)
DF2 = data.frame(user_id = c(rep(27, 7), rep(11, 7)),
date = as.Date(rep(c('2016-01-01', '2016-01-03', '2016-01-05', '2016-01-07', '2016-01-10', '2016-01-14', '2016-01-16'), 2)),
value = round(rnorm(14, 15, 5), 1))
all_combinations <- expand.grid(user_id=unique(DF2$user_id),
date=seq(min(DF2$date), max(DF2$date), by="day"))
res <- DF2 %>%
merge(all_combinations, by=c('user_id','date'), all=TRUE) %>%
group_by(user_id) %>%
arrange(date) %>%
mutate(v_minus7=rollapply(value, width=8, FUN=function(x) sum(x, na.rm=TRUE), partial=TRUE, align='right'),
v_minus14=rollapply(value, width=15, FUN=function(x) sum(x, na.rm=TRUE), partial=TRUE, align='right')) %>%
filter(!is.na(value))
Here is another idea with findInterval to minimize comparisons and operations. First define a function to accomodate the basic part ignoring the grouping. The following function computes the cumulative sum, and subtracts the cumulative sum at each position from the one at its respective past date:
ff = function(date, value, minus)
{
cs = cumsum(value)
i = findInterval(date - minus, date, left.open = TRUE)
w = which(as.logical(i))
i[w] = cs[i[w]]
cs - i
}
And apply it by group:
do.call(rbind,
lapply(split(DF2, DF2$user_id),
function(x) data.frame(x,
minus7 = ff(x$date, x$value, 7),
minus14 = ff(x$date, x$value, 14))))
# user_id date value minus7 minus14
#11.8 11 2016-01-01 6.8 6.8 6.8
#11.9 11 2016-01-03 21.3 28.1 28.1
#11.10 11 2016-01-05 19.8 47.9 47.9
#11.11 11 2016-01-07 22.0 69.9 69.9
#11.12 11 2016-01-10 19.4 82.5 89.3
#11.13 11 2016-01-14 17.5 58.9 106.8
#11.14 11 2016-01-16 19.3 56.2 119.3
#27.1 27 2016-01-01 15.0 15.0 15.0
#27.2 27 2016-01-03 22.4 37.4 37.4
#27.3 27 2016-01-05 13.3 50.7 50.7
#27.4 27 2016-01-07 21.9 72.6 72.6
#27.5 27 2016-01-10 20.6 78.2 93.2
#27.6 27 2016-01-14 18.6 61.1 111.8
#27.7 27 2016-01-16 16.4 55.6 113.2
The above apply-by-group operation can, of course, be replaced by any method prefereable.
Here are some approaches using zoo.
1) Define a function sum_last that given a zoo object takes the sum of the values whose times are within k days of the last day in the series and define a roll function which applies it to an entire series. Then use ave to apply roll to each user_id once for k=7 and once for k=14.
Note that this makes use of the coredata argument to rollapply that was introduced in the most recent version of zoo so be sure you don't have an earlier version.
library(zoo)
# compute sum of values within k time units of last time point
sum_last <- function(z, k) {
tt <- time(z)
sum(z[tt > tail(tt, 1) - k])
}
# given indexes ix run rollapplyr on read.zoo(DF2[ix, -1])
roll <- function(ix, k) {
rollapplyr(read.zoo(DF2[ix, -1]), k, sum_last, coredata = FALSE, partial = TRUE, k = k)
}
nr <- nrow(DF2)
transform(DF2,
v_minus7 = ave(1:nr, user_id, FUN = function(x) roll(x, 7)),
v_minus14 = ave(1:nr, user_id, FUN = function(x) roll(x, 14)))
2) An alternative would be to replace roll with the version shown below. This converts DF2[ix, -1] to "zoo" and merges it with a zero width grid with filled-in gaps. Then rollapply is applied to that and we use window to subset it back to the original times.
roll <- function(ix, k) {
z <- read.zoo(DF2[ix, -1])
g <- zoo(, seq(start(z), end(z), "day"))
m <- merge(z, g, fill = 0)
r <- rollapplyr(m, k, sum, partial = TRUE)
window(r, time(z))
}
Try runner package if you want to calculate on time/date windows. Go to github documentation and check Windows depending on date section.
library(runner)
DF2 %>%
group_by(user_id) %>%
mutate(
v_minus7 = sum_run(value, 7, idx = date),
v_minus14 = sum_run(value, 14, idx = date)
)
Benchmark here
library(data.table)
library(dplyr)
library(zoo)
library(tbrf)
set.seed(3737)
DF2 = data.frame(user_id = c(rep(27, 7), rep(11, 7)),
date = as.Date(rep(c('2016-01-01', '2016-01-03', '2016-01-05', '2016-01-07', '2016-01-10', '2016-01-14', '2016-01-16'), 2)),
value = round(rnorm(14, 15, 5), 1))
# example 1
data_table <- function(DF2) {
setDT(DF2)[, `:=`(v_minus7 = sum(DF2$value[DF2$user_id == user_id][data.table::between(DF2$date[DF2$user_id == user_id], date-7, date, incbounds = TRUE)]),
v_minus14 = sum(DF2$value[DF2$user_id == user_id][data.table::between(DF2$date[DF2$user_id == user_id], date-14, date, incbounds = TRUE)])),
by = c("user_id", "date")][]
}
# example 2
dplyr_grid <- function(DF2) {
all_combinations <- expand.grid(user_id=unique(DF2$user_id),
date=seq(min(DF2$date), max(DF2$date), by="day"))
DF2 %>%
merge(all_combinations, by=c('user_id','date'), all=TRUE) %>%
group_by(user_id) %>%
arrange(date) %>%
mutate(v_minus7=rollapply(value, width=8, FUN=function(x) sum(x, na.rm=TRUE), partial=TRUE, align='right'),
v_minus14=rollapply(value, width=15, FUN=function(x) sum(x, na.rm=TRUE), partial=TRUE, align='right')) %>%
filter(!is.na(value))
}
# example 3
dplyr_tbrf <- function(DF2) {
DF2 %>%
group_by(user_id) %>%
tbrf::tbr_sum(value, date, unit = "days", n = 7) %>%
arrange(user_id, date) %>%
rename(v_minus7 = sum) %>%
tbrf::tbr_sum(value, date, unit = "days", n = 14) %>%
rename(v_minus14 = sum)
}
# example 4
runner <- function(DF2) {
DF2 %>%
group_by(user_id) %>%
mutate(
v_minus7 = sum_run(value, 7, idx = date),
v_minus14 = sum_run(value, 14, idx = date)
)
}
microbenchmark::microbenchmark(
runner = runner(DF2),
data.table = data_table(DF2),
dplyr = dplyr_tbrf(DF2),
dplyr_tbrf = dplyr_tbrf(DF2),
times = 100L
)
# Unit: milliseconds
# expr min lq mean median uq max neval
# runner 1.478331 1.797512 2.350416 2.083680 2.559875 9.181675 100
# data.table 5.432618 5.970619 7.107540 6.424862 7.563405 13.674661 100
# dplyr 63.841710 73.652023 86.228112 79.861760 92.304231 256.841078 100
# dplyr_tbrf 60.582381 72.511075 90.175891 80.435700 92.865997 307.454643 100
Here is a new option using dplyr and tbrf
library(tbrf)
library(dplyr)
set.seed(3737)
DF2 = data.frame(user_id = c(rep(27, 7), rep(11, 7)),
date = as.Date(rep(c('2016-01-01', '2016-01-03', '2016-01-05', '2016-01-07', '2016-01-10', '2016-01-14', '2016-01-16'), 2)),
value = round(rnorm(14, 15, 5), 1))
DF2 %>%
group_by(user_id) %>%
tbrf::tbr_sum(value, date, unit = "days", n = 7) %>%
arrange(user_id, date) %>%
rename(v_minus7 = sum) %>%
tbrf::tbr_sum(value, date, unit = "days", n = 14) %>%
rename(v_minus14 = sum)
Creates a tibble:
# A tibble: 14 x 5
user_id date value v_minus7 v_minus14
<dbl> <date> <dbl> <dbl> <dbl>
1 11 2016-01-01 6.8 6.8 21.8
2 27 2016-01-01 15 15 21.8
3 11 2016-01-03 21.3 28.1 65.5
4 27 2016-01-03 22.4 37.4 65.5
5 11 2016-01-05 19.8 47.9 98.6
6 27 2016-01-05 13.3 50.7 98.6
7 11 2016-01-07 22 69.9 142.
8 27 2016-01-07 21.9 72.6 142.
9 11 2016-01-10 19.4 82.5 182.
10 27 2016-01-10 20.6 78.2 182.
11 11 2016-01-14 17.5 58.9 219.
12 27 2016-01-14 18.6 61.1 219.
13 11 2016-01-16 19.3 56.2 232.
14 27 2016-01-16 16.4 55.6 232.
I suspect this isn't the fastest solution with larger datasets, but it works well in dplyr chains.
I've endlessly looked for this and somehow nothing has solved this simple problem.
I have a dataframe called Prices in which there are 4 columns, one of which is a list of historical dates - the other 3 are lists of prices for products.
1 10/10/2016 53.14 50.366 51.87
2 07/10/2016 51.93 49.207 50.38
3 06/10/2016 52.51 49.655 50.98
4 05/10/2016 51.86 49.076 50.38
5 04/10/2016 50.87 48.186 49.3
6 03/10/2016 50.89 48.075 49.4
7 30/09/2016 50.19 47.384 48.82
8 29/09/2016 49.81 46.924 48.4
9 28/09/2016 49.24 46.062 47.65
10 27/09/2016 46.52 43.599 45.24
The list is 252 prices long. How can I have my output stored with the latest date at the bottom of the list and the corresponding prices listed with the latest prices at the bottom of the list?
Another tidyverse solution and I think the simplest one is:
df %>% map_df(rev)
or using just purrr::map_df we can do map_df(df, rev).
If you just want to reverse the order of the rows in a dataframe, you can do the following:
df<- df[seq(dim(df)[1],1),]
Just for completeness sake. There is actually no need to call seq here. You can just use the :-R-logic:
### Create some sample data
n=252
sampledata<-data.frame(a=sample(letters,n,replace=TRUE),b=rnorm(n,1,0.7),
c=rnorm(n,1,0.6),d=runif(n))
### Compare some different ways to reorder the dataframe
myfun1<-function(df=sampledata){df<-df[seq(nrow(df),1),]}
myfun2<-function(df=sampledata){df<-df[seq(dim(df)[1],1),]}
myfun3<-function(df=sampledata){df<-df[dim(df)[1]:1,]}
myfun4<-function(df=sampledata){df<-df[nrow(df):1,]}
### Microbenchmark the functions
microbenchmark::microbenchmark(myfun1(),myfun2(),myfun3(),myfun4(),times=1000L)
Unit: microseconds
expr min lq mean median uq max neval
myfun1() 63.994 67.686 117.61797 71.3780 87.3765 5818.494 1000
myfun2() 63.173 67.686 99.29120 70.9680 87.7865 2299.258 1000
myfun3() 56.610 60.302 92.18913 62.7635 76.9155 3241.522 1000
myfun4() 56.610 60.302 99.52666 63.1740 77.5310 4440.582 1000
The fastest way in my trial here was to use df<-df[dim(df)[1]:1,]. However using nrow instead of dim is only slightly slower. Making this a question of personal preference.
Using seq here definitely slows the process down.
UPDATE September 2018:
From a speed view there is little reason to use dplyr here. For maybe 90% of users the basic R functionality should suffice. The other 10% need to use dplyr for querying a database or need code translation into another language.
## hmhensen's function
dplyr_fun<-function(df=sampledata){df %>% arrange(rev(rownames(.)))}
microbenchmark::microbenchmark(myfun3(),myfun4(),dplyr_fun(),times=1000L)
Unit: microseconds
expr min lq mean median uq max neval
myfun3() 55.8 69.75 132.8178 103.85 139.95 8949.3 1000
myfun4() 55.9 68.40 115.6418 100.05 135.00 2409.1 1000
dplyr_fun() 1364.8 1541.15 2173.0717 1786.10 2757.80 8434.8 1000
Yet another tidyverse solution is:
df %>% arrange(desc(row_number()))
Another option is to order the list by the vector you want to sort it by,
> data[order(data$Date), ]
# A tibble: 10 x 4
Date priceA priceB priceC
<dttm> <dbl> <dbl> <dbl>
1 2016-09-27 00:00:00 46.5 43.6 45.2
2 2016-09-28 00:00:00 49.2 46.1 47.6
3 2016-09-29 00:00:00 49.8 46.9 48.4
4 2016-09-30 00:00:00 50.2 47.4 48.8
5 2016-10-03 00:00:00 50.9 48.1 49.4
6 2016-10-04 00:00:00 50.9 48.2 49.3
7 2016-10-05 00:00:00 51.9 49.1 50.4
8 2016-10-06 00:00:00 52.5 49.7 51.0
9 2016-10-07 00:00:00 51.9 49.2 50.4
10 2016-10-10 00:00:00 53.1 50.4 51.9
Then if you are so inclined, you want to flip the order, reverse it,
> data[rev(order(data$Date)), ]
# A tibble: 10 x 4
Date priceA priceB priceC
<dttm> <dbl> <dbl> <dbl>
1 2016-10-10 00:00:00 53.1 50.4 51.9
2 2016-10-07 00:00:00 51.9 49.2 50.4
3 2016-10-06 00:00:00 52.5 49.7 51.0
4 2016-10-05 00:00:00 51.9 49.1 50.4
5 2016-10-04 00:00:00 50.9 48.2 49.3
6 2016-10-03 00:00:00 50.9 48.1 49.4
7 2016-09-30 00:00:00 50.2 47.4 48.8
8 2016-09-29 00:00:00 49.8 46.9 48.4
9 2016-09-28 00:00:00 49.2 46.1 47.6
10 2016-09-27 00:00:00 46.5 43.6 45.2
If you wanted to do this in base R use:
df <- df[rev(seq_len(nrow(df))), , drop = FALSE]
All other base R solutions posted here will have problems in the edge cases of zero row data frames (seq(0,1) == c(0, 1), that's why we use seq_len) or single column data frames (data.frame(a=7:9)[3:1,] == 9:7, that's why we use , drop = FALSE).
If you want to stick with base R, you could also use lapply().
do.call(cbind, lapply(df, rev))