How to sort column names of dataframe in R - r

I need to use R to print dataset of a dataframe so that columns are in alphabetical order. It sounds sorting column name is required. I tried sort (data.frame$) but it didn't work. Can anybody help me?

You can use the code below
df[order(names(df))]
or
df[sort(names(df))]

Related

For and if loop in R

I am trying to get the following done: I have two columns (lets say codeA and codeB) in a dataframe A and want to compare these characters to a column (codeC) of another dataframe B. The codeA and codeB are the same in most cases, if they are not the same, the code (A/B) that matches codeC should be written in a new column.
So far I did not manage to achieve this result in combining if and for loops in R. Can someone help me?
Gretly appreciated!
I tried to code it using if and for loop but did not get the result needed.

How can I exclude partial duplications of a dataframe?

I am a beginner in R and I have a question about dataframes.
In my case, I have this data.frame as a example:
I just want one ENSEMBL_ID Per SYMBOL, so I'd like to get rid of one of these. Can someone tell me how could I do this? In this case unique(data.frame) does not work as there is a difference in the third column.

How to index when using colnames to create a list with all colnames in R(data frames)

I have a problem regarding the following issue:
I need all columnames aport from V1 till the end V200 in a list, but I don't know how and where to insert the index into these lines of code.
Like this, it gives me a list of all columnames but I don't need the first two. Please help, thank you!
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Update, once more, thanks to akrun for a better/shorter solution:
names(df)[3:ncol(df)]
For dataframes there is no need to use colnames, it's the same like names. The difference is only in case you're dealing with matrices

R function for identifying values from one column in another?

I have two different data frames, each of them consisting of a list of "genes" and a list of "interactors" (other genes). Is it possible with R to check if there any "genes" from one list that are also present in any of the columns of "interactors" from the other data frame, and vice-versa?
I am quite new in R, so perhaps there is an easy way to perform this, but I don't even know how to look for it.
Thanks in advance!
Guillermo.
please can you show a sample of your data?
In any case, I guess the following is what you need:
df_common<-data.frame(df[which(df$genes %in% df$interactors),])
it is checking which elements in the column "genes" in the data frame df are also present %in% the column "interactors" in the same data frame
Is it this what you are looking for? if not, please paste input and desired output

Indicating over letters in R

Assume there's a list in R with a variable which contains character fields. I want to output all values which begin with certain letters like "ab". How can I do this? Thanks for help.
As the OP didn't provide any reproducible example, based on the description, it seems to be a data.frame, we can use grep to subset the elements in the column that begin with 'ab'.
grep('^ab',yourdata$yourcol, value=TRUE)

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