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Is there a reason why R won't allow me to have a number as the column name of my dataframe?
Also noticed that if i do data.frame(XX) it adds an X to all the column headers that have numbers at the front.
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Names in MySQL can start with a digit, but cannot be entirely digits — they cannot be confusable with an integer. So, no.
Yes, because R won't allow names of objects to start with numbers.
To access the names of a Pandas dataframe, we can the method columns(). For example, if our dataframe is called df we just type print(df. columns) to get all the columns of the Pandas dataframe. After this, we can work with the columns to access certain columns, rename a column, and so on.
To access a specific column in a dataframe by name, you use the $ operator in the form df$name where df is the name of the dataframe, and name is the name of the column you are interested in. This operation will then return the column you want as a vector.
Works for me
data.frame(`1`=rnorm(3), `2`=head(letters,3), check.names=FALSE) # 1 2 # 1 0.5019 a # 2 1.1148 b # 3 0.4787 c Yes, because R won't allow names of objects to start with numbers. If you were to call attach() with the data.frame, this would cause some issues.
data.frame (and read.table) function has the check.names parameter (default is TRUE)
If
TRUEthen the names of the variables in the data frame are checked to ensure that they are syntactically valid variable names and are not duplicated. If necessary they are adjusted (bymake.names) so that they are.
From ?make.names:
A syntactically valid name consists of letters, numbers and the dot or underline characters and starts with a letter or the dot not followed by a number. [...] The character "
X" is prepended if necessary.
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