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| − | ==Importing and exporting data in '''R'''==
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| − | '''R''' allows data importing from many different source formats. The
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| − | most common used functions to import data are the ''read''
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| − | functions. The following code can be used to import a .csv table named
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| − | "forest-data.csv" from the folder "my-working-folder". The data is
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| − | stored in an object named ''data''.
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| − | data <- read.csv("C:/Program Files/... /my-working-folder/forest-data.csv")
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| − | Note that ''/'' or ''\\'' instead of ''\'' is used in '''R''' to define the the file path in
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| − | your computer.
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| − | A more convenient way of working is defining first the working directory
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| − | from where the data will be imported and where the result can be stored.
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| − | The actual working directory can be consulted by ''getwd()'', and the
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| − | objects contained there by ''dir()''. The working directory can be
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| − | defined as described below.
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| − | setwd("D:/Data/... /R-course/")
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| − | Once defined the working directory, the file can be imported without
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| − | specifying the file path as follows:
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| − | data <- read.csv("forest-data.csv")
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| − | All the objects created or imported to '''R''' are temporary stored
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| − | in the '''R'''-workspace. Objects in the workspace can be removed by
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| − | using the ''rm()'' function. All objects in the workspace are usually
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| − | lost after finishing the '''R''' session. The easiest option to store
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| − | permanently an object in the working directory is by using the ''write()'' functions. The code to save as a .csv file the object ''d''
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| − | is shown below.
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| − | write.csv(d, "Data-saved.csv")
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