Inputting from a delimited input file (read.delim)
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read.delim(file, header = TRUE, sep = "\t", quote = "\"",
           dec = ".", fill = TRUE, comment.char = "", ...)

read.delim2(file, header = TRUE, sep = "\t", quote = "\"",
            dec = ",", fill = TRUE, comment.char = "", ...)

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You've been using the Wrong Random Numbers! - Monte Carlo Simulations
https://www.youtube.com/watch?v=DbFJdjpTPok

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tibble table 
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 tibble() is a trimmed down version of data.frame() that: 
    
    1) Never coerces inputs (i.e. strings stay as strings!). 
    2)  Never adds row.names. 
    3)  Never munges column names. 
    4)  Only recycles length 1 inputs. 
    5)  Evaluates its arguments lazily and in order. 
    6)  Adds tbl_df class to output. 
    7) Automatically adds column names. 

library(tibble)
help(package=tibble)

a <- 1:100
b <-a*2
data1<-data.frame(a,b)
data2<-tibble(a, b)

> data2
# A tibble: 100 x 2
       a     b
   <int> <dbl>
 1     1     2
 2     2     4
 3     3     6
 4     4     8
 5     5    10
 6     6    12
 7     7    14
 8     8    16
 9     9    18
10    10    20
# ... with 90 more rows

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Inputting other types of data sets other ones 
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library(haven)

read_dta       Read and write Stata DTA files.

read_por       Read SPSS ('.sav', '.zsav', '.por') files. Write '.sav' and '.zsav' files.

read_sas       Read and write SAS files.

read_sav       Read SPSS ('.sav', '.zsav', '.por') files. Write '.sav' and '.zsav' files.

read_spss     Read SPSS ('.sav', '.zsav', '.por') files. Write '.sav' and '.zsav' files.

read_stata    Read and write Stata DTA files.

read_xpt      Read and write SAS transport files

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relative vs. absolute address 
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Absolute address
----------------
   > x<-read.csv("c:/temp/ibm.csv")

Relative address
------------------
   Our programs read (retrieve) data from the current working directory)

  > setwd("c:/temp")
  > getwd()
    [1] "c:/temp"

  > x<-read.csv("ibm.csv")

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