I have a .csv dataset that gets dumped everyday which I use to generate a daily list for tracking participants using a R script. I would like to automate this R script, however in order to do so, I need to read in the .csv using Sys.Date().
The .csv dataset is named: DumpedList_2013-11-27 (The date will always be today's date).
I would like to import this into the script, like I would for .Rdata file.
load(paste('/srv/Data/Baseline2/baseline2_', Sys.Date(), '.Rdata',sep=''))
What is the equivalent of the command above for reading in .csv files?
I have tried load and read.csv commands, but get error messages:
data=read.csv('P:/DirectoryPath/DumpedList_',Sys.Date(),'.csv')
I also attempted to create todaydate=Sys.Date() and then used it to load the data, but error messages again. a=load(paste("P:/DirectoryPath/DumpedList_",todaydate,".csv"))
Any insight?
By default paste will separate with spaces, use paste0 to join strings together seamlessly:
read.csv(paste0('P:/DirectoryPath/DumpedList_',Sys.Date(),'.csv'))
Related
I have a code that generates several very large dataframes in a loop. Each one has around 300 million rows so I run out of memory before the loop is over. I am trying to export each dataframe once it is constructed within the loop and then remove it to free up space in my R environment before I start constructing the next.
The issue is how to export these very large datasets. I tried using fwrite from the data.table package but when I open the csv file I get an empty csv file called Book1 instead. I also tried saving it as a dta file using write.dta from the foreign package but Stata tells me it is corrupted when I try opening it.
When saving it as .csv with fwrite and opening it with Stata it worked perfectly!
I do not have any expertise on R and I have to convert RData files to CSV to analyze the data. I followed the following links to do this: Converting Rdata files to CSV and "filename.rdata" file Exploring and Converting to CSV. The second option seemed to be a simpler as I failed to understand the first one. This is what I have tried till now and the results along with it:
>ddata <- load("input_data.RData")
>print(ddata)
[1] "input_data"
> print(ddata[[1]])
[1] "input_data"
> write.csv(ddata,"test.csv")
From the first link I learnt that we can see the RData type and when I did str(ddata) I found out that it is a List of size 1. Hence, I checked to see if print(ddata[[1]]) would print anything apart from just "input_data". With the write.csv I was able to write it to a csv without any errors but it has just the following 2 lines inside the CSV file:
"","x"
"1","input_data"
Can you please help me understand what am I doing wrong and show a way to get all the details in a csv?
The object ddata contains the name of the object(s) that load() created. Try typing the command ls(). That should give you the names of the objects in your environment. One of them should be input_data. That is the object. If it is a data frame (str(input_data)), you can create the csv file with
write.csv(input_data, "test.csv")
This is more of a curiosity.
Sometimes I modify csv files from Excel rather than R (suppose I manage to find a missing piece of info and I type it in the csv file), of course maintaining commas and quotes as they were.
Every time I do this, R becomes unable to read the csv file, i.e. it imports a single column as it appears on Excel, rather than separating the values (no options like sep= or quote= change this).
Does anyone know why this happens?
Thanks a lot
An example
This was readable:
state,"city","county"
AK,"Anchorage",""
AK,"Haines",""
AK,"Juneau","Juneau"
After adding the missing info under "county", R fails to import it as a data frame, reading it instead as a single vector.
state,"city","county"
AK,"Anchorage","Anchorage"
AK,"Haines","Haines"
AK,"Juneau","Juneau"
Edit:
I'm just running the basic read.csv
df <- read.csv("C:/directory/df.csv")
I have multiple excel files in multiple directories that I am reading into R. However, I don't want to read in EVERY excel file; I only want to read in the most recent ones (for example, only the ones created in the last month). Is there a way to do this?
Currently I am using this to read in all of the excel files, which is working just fine:
filenames <- Sys.glob(file.path('(name of dir)', "19*", "Electrode*02.xlsx")) <br>
elecsheet <- do.call("cbind", lapply(filenames, read_excel))
Somewhere in this second line of code (I think), I need to tell R to look at the metadata and only read in the excel files that have been created since a certain date.
Thank you!
I am wondering is it possible to read an excel file that is currently open, and capture things you manually test into R?
I have an excel file opened (in Windows). In my excel, I have connected to a SSAS cube. And I do some manipulations using PivotTable Fields (like changing columns, rows, and filters) to understand the data. I would like to import some of the results I see in excel into R to create a report. (I mean without manually copy/paste the results into R or saving excel sheets to read them later). Is this a possible thing to do in R?
UPDATE
I was able to find an answer. Thanks to awesome package created by Andri Signorell.
library(DescTools)
fxls<-GetCurrXL()
tttt<-XLGetRange(header=TRUE)
I was able to find an answer. Thanks to awesome package created by Andri Signorell.
library(DescTools)
fxls<-GetCurrXL()
tttt<-XLGetRange(header=TRUE)
Copy the values you are interested in (in a single spread sheet at a time) to clipboard.
Then
dat = read.table('clipboard', header = TRUE, sep = "\t")
You can save the final excel spreadsheet as a csv file (comma separated).
Then use read.csv("filename") in R and go from there. Alternatively, you can use read.table("filename",sep=",") which is the more general version of read.csv(). For tab separated files, use sep="\t" and so forth.
I will assume this blog post will be useful: http://www.r-bloggers.com/a-million-ways-to-connect-r-and-excel/
In the R console, you can type
?read.table
for more information on the arguments and uses of this function. You can just repeat the same call in R after Excel sheet changes have been saved.