Why is R adding empty factors to my data? - r

I have a simple data set in R -- 2 conditions called "COND", and within those conditions adults chose between one of 2 pictures, we call house or car. This variable is called "SAW"
I have 69 people, and 69 rows of data
FOR SOME Reason -- R is adding an empty factor to both, How do I get rid of it?
When I type table to see how many are in each-- this is the output
table(MazeData$SAW)
car house
2 9 59
table(MazeData$COND)
Apples No_Apples
2 35 33
Where the heck are these 2 mystery rows coming from? it wont let me make my simple box plots and bar plots or run t.test because of this error - can someone help? thanks!!

Related

Cluster analysis in R on large data set

I have a data set with rankings as the column names and about 15,000 contestants. My data looks like:
contestant
1
2
3
4
101
13
0
5
12
14
0
1
34
6
...
...
...
...
...
500
0
2
23
3
I've been working on doing cluster analysis on this dataset. The dendrograms are obviously not very helpful with this dataset--it produces a thick block line because of the large number of entries.
I'm wondering if there is a better way to do cluster analysis with this type of data. I've tried
fviz_cluster()
and similar commands, as well as went through multiple tutorials. Many tutorials guided me through making dendograms. The data all seems to be different than mine (comparing two variables, etc) and much smaller. Essentially, I'm asking which types of cluster analysis may work well with this type of data.

R - Using Stringr to identify a string across hundreds of rows

I have a database where some people have multiple diagnoses. I posted a similar question in the past, but now have some more nuances I need to work through:
R- How to test multiple 100s of similar variables against a condition
I have this dataset (which was an import of a SAS file)
ID dx1 dx2 dx3 dx4 dx5 dx6 .... dx200
1 343 432 873 129 12 123 3445
2 34 12 44
3 12
4 34 56
Initially, I wanted to be able to create a new variable if any of the "dxs" equals a certain number without using hundreds of if statements? All the different variables have the same format (dx#). So I used the following code:
Ex:
dataset$highbloodpressure <- rowSums(screen[0:832] == "410") > 0
This worked great. However, there are many different codes for the same diagnosis. For example, a heart attack can be defined as:
410.1,
410.71,
410.62,
410.42,
...this goes on for 20 additional codes. BUT! They all start with 410.
I thought about using stringr (the variable is a string), to identify the common code components (410, for the example above), but am not sure how to use it in the context of rowsums.
If anyone has any suggestions for this, please let me know!
Thanks for all the help!
You can use the grepl() function that returns TRUE if a value is present. In order to check all columns simultaneously, just collapse all of them to one character per row:
df$dx.410 = NA
for(i in 1:dim(df)[1]){
if(grepl('410',paste(df[i,2:200],collapse=' '))){
df$dx.410[i]="Present"
}
}
This will loop through all lines, create one large character containing all diagnoses for this case and write "Present" in column dx.410 if any column contains a 410-diagnosis.
(The solution expects the data structure you have here with the dx-variables in columns 2 to 200. If there are some other columns, just adjust these numbers)

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: 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.

Excel: Select data for graph

To put it simple, I have three columns in excel like the ones below:
Vehicle x y
1 10 10
1 15 12
1 12 9
2 8 7
2 11 6
3 7 12
x and y are the coordinates of customers assigned to the corresponding vehicle. This file is the output of a program I run in advance. The list will always be sorted by vehicle, but the number of customers assigned to vehicle "k" may change from one experiment to the next.
I would like to plot a graph containing 3 series, one for each vehicle, where the customers of each vehicle would appear (as dots in 2D based on their x- and y- values) in different color.
In my real file, I have 12 vehicles and 3200 customers, and the ranges change from one experiment to the next, so I would like to automate the process, i.e copy-paste the list on my excel and see the graph appear automatically (if this is possible).
Thanks in advance for your time and effort.
EDIT: There is a similar post here: Use formulas to select chart data but requires the use of VB. Moreover, I am not sure whether it has been indeed answered.
you should try this free online tool - www.cloudyexcel.com/excel-to-graph/

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