Value <- c(2,3,5,2,5,8,17,3,5)
Event <- c(1,1,2,2,2,1,1,2,2)
group <- data.frame(pt=Value, Event=Event)
I have data like above and I would like to group events in a way that would result into following.
Event Value
1 2.5
2 4
1 12.5
2 4
Thank you in advance.
We can create a grouping variable with rleid from data.table, use that to get the mean of 'pt' as well as return the first value of 'Event'
library(dplyr)
library(data.table)
group %>%
group_by(grp = rleid(Event)) %>%
summarise(Event = first(Event), Value = mean(pt)) %>%
select(-grp)
# A tibble: 4 x 2
# Event Value
# <dbl> <dbl>
#1 1 2.5
#2 2 4
#3 1 12.5
#4 2 4
Or using tapply/rle in base R
with(group, tapply(pt, with(rle(Event),
rep(seq_along(values), lengths)), FUN = mean))
# 1 2 3 4
# 2.5 4.0 12.5 4.0
Another option is using cumsum:
dfs %>%
mutate(gr = cumsum(Event != lag(Event, default = 0))) %>%
group_by(gr, Event) %>% summarise(mean_Value = mean(Value)) %>%
ungroup()
Related
I am trying to figure out a fast way to calculate the number of "first times" a specified character appears in a dataframe column, by groups. In this example, I am trying to summarize (sum) the number of first times, for each Period, the State of "X" appears, grouped by ID. I am looking for a fast way to process this because it is to be run against a database of several million rows. Maybe there is a good solution using the data.table package?
Immediately below I illustrate what I am trying to achieve, and at the bottom I post the code for the dataframe called testDF.
Code:
testDF <-
data.frame(
ID = c(rep(10,5),rep(50,5),rep(60,5)),
Period = c(1:5,1:5,1:5),
State = c("A","B","X","X","X",
"A","A","A","A","A",
"A","X","A","X","B")
)
Maybe we can group by 'ID' first and then create the column and then do a group by 'period' and summarise
library(dplyr)
testDF %>%
group_by(ID) %>%
mutate(`1stStateX` = row_number() == which(State == "X")[1]) %>%
group_by(Period) %>%
summarise(`1stStateX` = sum(`1stStateX`, na.rm = TRUE), .groups = 'drop')
-output
# A tibble: 5 × 2
Period `1stStateX`
<int> <int>
1 1 0
2 2 1
3 3 1
4 4 0
5 5 0
Another option will be to slice after grouping by 'ID', get the count and use complete to fill the 'Period' not available
library(tidyr)
testDF %>%
group_by(ID) %>%
slice(match('X', State)) %>%
ungroup %>%
count(Period, sort = TRUE ,name = "1stStateX") %>%
complete(Period = unique(testDF$Period),
fill = list(`1stStateX` = 0))
-output
# A tibble: 5 × 2
Period `1stStateX`
<int> <int>
1 1 0
2 2 1
3 3 1
4 4 0
5 5 0
Or similar option in data.table
library(data.table)
setDT(testDF)[, `1stStateX` := .I == .I[State == 'X'][1],
ID][, .(`1stStateX` = sum(`1stStateX`, na.rm = TRUE)), by = Period]
-output
Period 1stStateX
<int> <int>
1: 1 0
2: 2 1
3: 3 1
4: 4 0
5: 5 0
I have some groups of data and in each group there is one number that is a multiple of 7.
For each group, I want to subtract the first value from that multiple.
Reproducible example:
temp.df <- data.frame("temp" = c(48:55, 70:72, 93:99))
temp.df$group <- cumsum(c(TRUE, diff(temp.df$temp) > 1))
Expected result:
group 1: 49-48 = 1
group 2: 70-70 = 0
group 3: 98-93 = 5
Can you suggest me a way that do not require using any loop?
You can get the number divisible by 7 in each group and subtract it with first value.
This can be done in base R using aggregate.
aggregate(temp~group, temp.df, function(x) x[x %% 7 == 0] - x[1])
# group temp
#1 1 1
#2 2 0
#3 3 5
You can also do this using dplyr
library(dplyr)
temp.df %>%
group_by(group) %>%
summarise(temp = temp[temp %% 7 == 0] - first(temp))
and data.table
library(data.table)
setDT(temp.df)[, .(temp = temp[temp %% 7 == 0] - first(temp)), group]
We can also do
library(dplyr)
temp.df %>%
group_by(group) %>%
summarise(temp = temp[which.max(!temp %% 7)] - first(temp))
# A tibble: 3 x 2
# group temp
# <int> <int>
#1 1 1
#2 2 0
#3 3 5
thank you in advance for your response! I am working in Rstudio, trying to create a specific table format that my customer is looking for. Specifically, I would like to show each metric as a row and the group_by variable, in this case application type, as a column. I'm using group_by to consolidate all my data by application type, and I'm using the summarise function to create the new variables.
subs <- data.frame(
App_type = c('A','A','A','B','B','B','C','C','C','C'),
Has_error = c(1,1,1,0,0,1,1,0,1,1),
Has_critical_error = c(1,0,1,0,0,1,0,0,1,1)
)
I'm able to group the submissions together by application type to see total submissions with errors and total with critical errors. Here's what I've done -
subs %>%
group_by(App_type) %>%
summarise(
total_sub = n(),
total_error = sum(Has_error),
total_critical_error = sum(Has_critical_error)
)
# A tibble: 3 x 4
App_type total_sub total_error total_critical_error
<fct> <int> <dbl> <dbl>
1 A 3 3 2
2 B 3 1 1
3 C 4 3 2
However, my customer would like to see it this way with application totals.
A B C TOTAL
1 total_sub 3 3 4 10
2 total_error 3 1 3 7
3 total_critical_error 2 1 2 5
We can pivot to 'wide' format after reshaping to 'long' and then change the column name 'name' to rowname
library(dplyr)
library(tidyr)
library(tibble)
subs %>%
group_by(App_type) %>%
summarise(
total_sub = n(),
total_error = sum(Has_error),
total_critical_error = sum(Has_critical_error)) %>%
pivot_longer(cols = -App_type) %>%
pivot_wider(names_from = App_type, values_from = value) %>%
mutate(TOTAL = A + B + C) %>%
column_to_rownames("name")
# A B C TOTAL
#total_sub 3 3 4 10
#total_error 3 1 3 7
#total_critical_error 2 1 2 5
Or another option is transpose from data.table
library(data.table)
data.table::transpose(setDT(out), make.names = 'App_type',
keep.names = 'name')[, TOTAL := A + B + C][]
where out is the OP's summarised output
out <- subs %>%
group_by(App_type) %>%
summarise(
total_sub = n(),
total_error = sum(Has_error),
total_critical_error = sum(Has_critical_error)
)
Or with base R
addmargins(t(cbind(total_sub = as.integer(table(subs$App_type)),
rowsum(subs[-1], subs$App_type))), 2)
# A B C Sum
#total_sub 3 3 4 10
#Has_error 3 1 3 7
#Has_critical_error 2 1 2 5
data=data.frame("StudentID"=c(1,2,3,4,5),
"Class"=c(1,2,2,3,3),
"Type"=c('A','A','B','B','B'))
Say you have data as shown above and you wish for summaries like this,
What is the effective solution to do this and output to a csv in organized way such as shown above?
Example data if there is weights involved and you wanted weighted counts and porporitons.portions.
data1=data.frame("StudentID"=c(1,2,3,4,5),
"Class"=c(1,2,2,3,3),
"Type"=c('A','A','B','B','B'),
"Weighting"=c(10,6,13,12,2))
One option is map
library(dplyr)
library(purrr)
map_dfr(names(data)[2:3], ~
data %>%
select(.x) %>%
group_by_at(.x) %>%
summarise(COUNT = n()) %>%
mutate(PROP = COUNT/sum(COUNT)))
# A tibble: 5 x 4
# Class COUNT PROP Type
#* <dbl> <int> <dbl> <fct>
#1 1 1 0.2 <NA>
#2 2 2 0.4 <NA>
#3 3 2 0.4 <NA>
#4 NA 2 0.4 A
#5 NA 3 0.6 B
Or with data.table by melting into 'long' format
library(data.table)
melt(setDT(data), id.var = 'StudentID')[, .(COUNT = .N),
.(variable, value)][, PROP := COUNT/sum(COUNT),.(variable)][]
Or with base R using table and prop.table
lapply(data[-1], function(x) {x1 <- table(x); x2 <- prop.table(x1); cbind(COUNT = x1, PROP = x2)})
Both summaries are simple, here I use dplyr. To combine them in the way you want, it's going to need to be slapped together in a somewhat inelegant way. You can remove the name col1 if you want
library(dplyr)
df1 <- data %>% group_by(Class) %>%
summarise(Count = n(), Prop = n() / nrow(data))
df2 <- data %>% group_by(Type) %>%
summarise(Count = n(), Prop = n() / nrow(data))
names(df1)[1] <- 'col1'
names(df2)[1] <- 'col1'
rbind(
c('Class', '', ''),
df1,
c('Type', '', ''),
df2
)
# A tibble: 7 x 3
col1 Count Prop
<chr> <chr> <chr>
1 Class "" ""
2 1 1 0.2
3 2 2 0.4
4 3 2 0.4
5 Type "" ""
6 A 2 0.4
7 B 3 0.6
My data frame looks something like the first two columns of the following
I want to add a third column, equal to the sum of the ID-group's last three observations for VAL.
Using the following command, I managed to get the output below:
df %>%
group_by(ID) %>%
mutate(SUM=rollsumr(VAL, k=3)) %>%
ungroup()
ID VAL SUM
1 2 NA
1 1 NA
1 3 6
1 4 8
...
I am now hoping to be able to fill the NAs that result for the group's cells in the first two rows.
ID VAL SUM
1 2 2
1 1 3
1 3 6
1 4 8
...
How do I do that?
I have tried doing the following
df %>%
group_by(ID) %>%
mutate(SUM=rollsumr(VAL, k=min(3, row_number())) %>%
ungroup()
and
df %>%
group_by(ID) %>%
mutate(SUM=rollsumr(VAL, k=3), fill = "extend") %>%
ungroup()
But both give me the same error, because I have groups of sizes <= 2.
Evaluation error: need at least two non-NA values to interpolate.
What do I do?
Alternatively, you can use rollapply() from the same package:
df %>%
group_by(ID) %>%
mutate(SUM = rollapply(VAL, width = 3, FUN = sum, partial = TRUE, align = "right"))
ID VAL SUM
<int> <int> <int>
1 1 2 2
2 1 1 3
3 1 3 6
4 1 4 8
Due to argument partial = TRUE, also the rows that are below the desired window of length three are summed.
Not a direct answer but one way would be to replace the values which are NAs with cumsum of VAL
library(dplyr)
library(zoo)
df %>%
group_by(ID) %>%
mutate(SUM = rollsumr(VAL, k=3, fill = NA),
SUM = ifelse(is.na(SUM), cumsum(VAL), SUM))
# ID VAL SUM
# <int> <int> <int>
#1 1 2 2
#2 1 1 3
#3 1 3 6
#4 1 4 8
Or since you know the window size before hand, you could check with row_number() as well
df %>%
group_by(ID) %>%
mutate(SUM = rollsumr(VAL, k=3, fill = NA),
SUM = ifelse(row_number() < 3, cumsum(VAL), SUM))