[R] determining the column index and grabbing only variables with a certain string in them

[Xiaohui]

1. which("Exat Name" == names(Data)   ## Assuming Data is your data.frame

2. grep("Variable", names(Data))

Xiaohui

Dimitri Liakhovitski wrote:
> Hello!
>
> I have a data set with almost 2,000 variables (called 'Data').
> I want to select only a set of variables that have a certain string in
> them (e.g., "Variable") - 'Variable.1', 'Variable.2', etc. until
> 'Variable.20'.
>
> 2 questions:
>
> 1. How can I determine the exact column index of a variable in the
> data frame if I know its exact name? (I am asking because names(Data)
> allows me to see only the last 1,348 variables)
> 2. How can I grab only variables that have a string "Variable" in
> their name using grep?
>
> Thank you!
> Dimitri
>
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