Static variable next to a dynamic variable in R - r

I posted yesterday another question but I feel I need to clarify it.
Let's say I have this code
md.NAME <- (subset(MyData, HotelName=="ALAMEDA"))
md.NAME.fc <- (subset(md.ALAMEDA, TIPO=="FORECAST"))
md.NAME.fc.bar <- (subset(md.ALAMEDA.fc, Market.Segment=="BAR"))
What I want is that NAME changes according to a variable set before those 3 lines are run,
So NAME is just dynamic in the sense that before these 3 lines I could say, ok, NAME now is equal to JOHN, but then, I could say that NAME is now equal to PATRIC.
So after running those 3 lines, twice (once for John and once for Patric) somehow in the environment I will get something like this:
6 dataframes, 3 for JOHN and 3 for PATRIC
DATAFRAME 1 WILL BE md.JOHN
DATAFRAME 2 WILL BE md.JOHN.fc
DATAFRAME 3 WILL BE md.JOHN.fc.bar
DATAFRAME 1 WILL BE md.PATRIC
DATAFRAME 2 WILL BE md.PATRIC.fc
DATAFRAME 3 WILL BE md.PATRIC.fc.bar
All the answers I had so far would help me only if "md" and "fc" or "fc.bar" are always the same. But I will have several variables like this, which will change a lot as far as the naming goes. So, it is the center part (NAME) the only one that should change.
I could even have something like:
md.test$NAME <- ...

Related

Merge columns with the same name R

I'm fairly new to R. I'm working with a data set that is incredibly redundant with a lot of columns (~400). There are several duplicate column names, however the data is not duplicate, so I need to sum the columns when collapsing them.
The columns all have a similar name that allows easy identification, so I'm hoping I can use that to my advantage.
I attempted to perform the following:
ColNames <- unique(colnames(df))
CombinedDf <- data.frame(sapply(ColNames, function(i)rowSums(Test[,ColNames==i, drop=FALSE])))
This works if I sum over the range of columns that only contain integers, but the issue is that other columns have strings and such in them, so rowSums throws a fit.
Assuming that the identifier is "XXX", how can I aggregate all the columns that are of the same name leaving the other columns as is?
Thank you for your time.
Edit: Sample data has been asked for, I cannot give the exact data as it is sensitive, but I will give an example:
Name COL1XXX COL2XXX COL1XXX COL3XXX COL2XXX Type
Henry 5 15 25 31 1 Orange
Tom 8 16 12 4 3 Green
Should return
Name COL1XXX COL2XXX COL3XXX Type
Henry 30 16 31 Orange
Tom 20 19 4 Green
I'm not really sure, but you may try transposing the data and then aggregating by unique names.
t_df=as.data.frame(t(df))
new_df=aggregate(t_df, by=list(rownames(t_df)),sum)
Again, without sample data I'm unsure if it'll work, but based on what you said, that might work.

R: Subsetting rows by group based on time difference

I have the following data frame:
group_id date_show date_med
1 1976-02-07 1971-04-14
1 1976-02-09 1976-12-11
1 2011-03-02 1970-03-22
2 1993-08-04 1997-06-13
2 2008-07-25 2006-09-01
2 2009-06-18 2005-11-12
3 2009-06-18 1999-11-03
I want to subset my data frame in such a way that the new data frame only shows the rows in which the values of date_show are further than 10 days apart but this condition should only be applied per group. I.e. if the values in the date_show column are less than 10 days apart but the group_ids are different, I need to keep both entries. What I want my result to look like based on the above table is:
group_id date_show date_med
1 1976-02-07 1971-04-14
1 2011-03-02 1970-03-22
2 1993-08-04 1997-06-13
2 2008-07-25 2006-09-01
2 2009-06-18 2005-11-12
3 2009-06-18 1999-11-03
Which row gets deleted isn't important because the reason why I'm subsetting in the first place is to calculate the number of rows I am left with after applying this criteria.
I've tried playing around with the diff function but I'm not sure how to go about it in the simplest possible way because this problem is already within another sapply function so I'm trying to avoid any kind of additional loop (in this case by group_id).
The df I'm working with has around 100 000 rows. Ideally, I would like to do this with base R because I have no rights to install any additional packages on the machine I'm working on but if this is not possible (or if solving this with an additional package would be significantly better), I can try and ask my admin to install it.
Any tips would be appreciated!

R Refer to (part of) data frame using string in R

I have a large data set in which I have to search for specific codes depending on what i want. For example, chemotherapy is coded by ~40 codes, that can appear in any of 40 columns called (diag1, diag2, etc).
I am in the process of writing a function that produces plots depending on what I want to show. I thought it would be good to specify what I want to plot in a input data frame. Thus, for example, in case I only want to plot chemotherapy events for patients, I would have a data frame like this:
Dataframe name: Style
Name SearchIn codes PlotAs PlotColour
Chemo data[substr(names(data),1,4)=="diag"] 1,2,3,4,5,6 | red
I already have a function that searches for codes in specific parts of the data frame and flags the events of interest. What i cannot do, and need your help with, is referring to a data frame (Style$SearchIn[1]) using codes in a data frame as above.
> Style$SearchIn[1]
[1] data[substr(names(data),1,4)=="diag"]
Levels: data[substr(names(data),1,4)=="diag"]
I thought perhaps get() would work, but I cant get it to work:
> get(Style$SearchIn[1])
Error in get(vars$SearchIn[1]) : invalid first argument
enter code here
or
> get(as.character(Style$SearchIn[1]))
Error in get(as.character(Style$SearchIn[1])) :
object 'data[substr(names(data),1,5)=="TDIAG"]' not found
Obviously, running data[substr(names(data),1,5)=="TDIAG"] works.
Example:
library(survival)
ex <- data.frame(SearchIn="lung[substr(names(lung),1,2) == 'ph']")
lung[substr(names(lung),1,2) == 'ph'] #works
get(ex$SearchIn[1]) # does not work
It is not a good idea to store R code in strings and then try to eval them when needed; there are nearly always better solutions for dynamic logic, such as lambdas.
I would recommend using a list to store the plot specification, rather than a data.frame. This would allow you to include a function as one of the list's components which could take the input data and return a subset of it for plotting.
For example:
library(survival);
plotFromSpec <- function(data,spec) {
filteredData <- spec$filter(data);
## ... draw a plot from filteredData and other stuff in spec ...
};
spec <- list(
Name='Chemo',
filter=function(data) data[,substr(names(data),1,2)=='ph'],
Codes=c(1,2,3,4,5,6),
PlotAs='|',
PlotColour='red'
);
plotFromSpec(lung,spec);
If you want to store multiple specifications, you could create a list of lists.
Have you tried using quote()
I'm not entirely sure what you want but maybe you could store the things you're trying to get() like
quote(data[substr(names(data),1,4)=="diag"])
and then use eval()
eval(quote(data[substr(names(data),1,4)=="diag"]), list(data=data))
For example,
dat <- data.frame("diag1"=1:10, "diag2"=1:10, "other"=1:10)
Style <- list(SearchIn=c(quote(data[substr(names(data),1,4)=="diag"]), quote("Other stuff")))
> head(eval(Style$SearchIn[[1]], list(data=dat)))
diag1 diag2
1 1 1
2 2 2
3 3 3
4 4 4
5 5 5
6 6 6

R: iterating through unique values of a vector in for loop

I'm new to R and I am having some trouble iterating through the unique element of a vector. I have a dataframe "School" with 700 different teachers. Each teacher has around 40 students.
I want to be able to loop through each teacher, create a graphs for the mean score of his/her students' over time, save the graphs in a folder and automatically email that folder to that teacher.
I'm just getting started and am having trouble setting up the for-loop. In Stata, I know how to loop through each unique element in a list, but am having trouble doing that in R. Any help would be appreciated.
School$Teacher School$Student School$ScoreNovember School$ScoreDec School$TeacherEmail
A 1 35 45 A#school.org
A 2 43 65 A#school.org
B 1 66 54 B#school.org
A 3 97 99 A#school.org
C 1 23 45 C#school.org
Your question seems a bit vague and it looks like you want us to write your whole project. Could you share what you have done so far and where exactly you are struggling?
see ?subset
School=data.frame(Teacher=c("A","B"), ScoreNovember=10:11, ScoreDec=13:14)
for (teacher in unique(School$Teacher)) {
teacher_df=subset(School, Teacher==teacher)
MeanScoreNovember=mean(teacher_df$ScoreNovember)
MeanScoreDec =mean(teacher_df$ScoreDec)
# do your plot
# send your email
}
I think you have 3 questions, which will need separate questions, how do I:
Create graphs
Automatically email output
Compute a subset mean based on group
For the 3rd one, I like using the plyr package, other people will recommend data.table or dplyrpackages. You can also use aggregate from base. To get a teacher's mean:
library(plyr)
ddply(School,.(Teacher),summarise,Nov_m=mean(ScoreNovember))
If you want per student per teacher, etc. just add between the columns, like:
library(plyr)
ddply(School,.(Teacher,Student),summarise,Nov_m=mean(ScoreNovember))
You could do that for each score column (and then chart it) if your data was long rather than wide you could also add the date ('November', 'Dec') as a group in the brackets, or:
library(plyr)
ddply(School,.(Teacher,Student),summarise,Nov_m=mean(ScoreNovember),Dec_m=mean(ScoreDec))
See if that helps with the 3rd, but look at splitting your questions up too.

R: Data transfer between two lists (source list smaller than target list)

I searched, but I couldn't find a similar question, so I apologize if I may have missed it.
My problem is actually pretty simple. I have two lists, a large one and a smaller one.
The smaller one consists of the averages of the data in the large list (ten lines have
been aggregated to form the small list -> it has one tenth the size of the larger one). All I want now, is to add a new column in the large list (which is no problem) and showing the averages next
to the original data. I am aware that I will see the average ten times, but that's fine.
I tried to solve this "problem" with simple list comparisons, e.g. (the relevant averages, as well as the original data have identical identifiers in the first column):
Large_List$Average_column[ Large_List$identifier == Small_List$identifier ] <- Small_List$Average[ Large_List$identifier == Small_List$identifier ];
Yet for some reason, it doesn't work. Probably because the target vector is larger than the source vector. I really tried a lot, and the only thing that seems to work is a loop structure. But that is no option because my list is way too large... I am sure there must be a smart solution to this simple issue.
UPDATE & SPECIFICATION
Thank you for your suggestions. But it seems I need to be more specific. The problem is that in most, but not in all cases, the average is formed out of ten consecutive datapoints. It may occur that less is used because of holes in the sample. Therefore, a replication will unfortunately not do the job.
Here’s an example (1_Ident is the minute identifier, 10_Ident being the ten minute identifier) :
Original_List:
1_Ident | 10_Ident|Minute_value|
July1-0| July1-0d| 1
July1-2| July1-0d| 1
(..)
July1-10| July1-0d| 1
July1-11| July1-1d| 1
July1-12| July1-1d| 2
July1-21| July1-21| 3
July1-31| July1-31| 2
Resulting Small_list:
10_Ident|Minute_average|
July1-0d| 1
July1-1d| 1.5
July1-2d| 3
July1-3d| 2
Desired outcome:
Large_List:
1_Ident |10_Ident|Minute_value|Minute_average|
July1-0| July1-0d| 1 1
July1-2| July1-0d| 1 1
(..)
July1-10| July1-0d| 1 1
July1-11| July1-1d| 1 1.5
July1-12| July1-1d| 2 1.5
July1-21| July1-21| 3 3
July1-31| July1-31| 2 2
I think the main problem is that the Small_list$Minute_average vector is not the same size as the Large_list$Minute_value vector. As said, one could compare the two lists line by line, doing a loop, but the size of the tables is >1M lines, so that won't work.
What I want to do is basically the following:
1) Look in the Large_List$10_Ident and compare it Small_List$10_Ident
2) Where the values match, transfer the corresponding Small_List$Minute_average value to Large_List$Minute_average
Thanks!
You could use match or merge to do that but why not just calculate the averages off the groupings?
Large_List$Average_column <- ave(Large_List$col_to_be_avgd,
Large_List$group_var,
FUN=mean, na.rm=TRUE)
The merge code might look like
merge( Large_List, Small_List[c('identifier', "Average"], by='identifier' , all.x=TRUE)

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