Differences

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--- r:input_output [2018/11/16 08:08] – [Redirecting Output to a File] hkimscil
+++ r:input_output [2019/09/20 10:32] (current) – [Reading from CSV Files] hkimscil
@@ Line 43: / Line 43: @@
 cat(conclusion, file="analysisReport.out", append=TRUE)</code>
-Without "append=TRUE" option, the content will be **overwritten** with the succeeding content.
+Without "append=TRUE" option, the content will be **overwritten** with the succeeding content. The above method is tedious and error prone. The second line has a different filename. The below method (making connection to file with file function) is better.
 <code>con <- file("analysisReport.out", "w")
@@ Line 69: / Line 69: @@
 Yates     Frank     1902 1994
 Smith     Kirstine  1878 1939
 </code>
-<code>> records <- read.fwf("fixed-width.txt", widths=c(10,10,4,-1,4))
+<code>> records <- read.fwf("http://commres.net/wiki/_export/code/r/input_output?codeblock=11", widths=c(10,10,4,-1,4))
 </code>
@@ Line 84: / Line 85: @@
 Smith      Kirstine   1878 1939
 </code>
+Funky variable names (V1, V2, . . .). Use the below method with "col.names=c()" option.
+<code>> records <- read.fwf("http://commres.net/wiki/_export/code/r/input_output?codeblock=11", widths=c(10,10,4,-1,4),
++                     col.names=c("Last","First","Born","Died"))
+> records
+        Last      First Born Died
+Fisher     R.A.       1890 1962
+Pearson    Karl       1857 1936
+Cox        Gertrude   1900 1978
+Yates      Frank      1902 1994
+Smith      Kirstine   1878 1939
+</code>
 ====== Reading Tabular Data Files ======
 <code>> dfrm <- read.table("filename")</code>
@@ Line 153: / Line 165: @@
 </code>
-<code>> tbl <- read.csv("filename")</code>
+<code>> tbl <- read.csv("filename.csv")
+> tbl</code>
-<code>> tbl <- read.csv("filename", header=FALSE)</code>
+<code>> tbl <- read.csv("filename.csv", header=FALSE)
+> tbl</code>
+<code>> tbl <- read.csv("filename.csv", header=FALSE, sep="\t")
+> tbl</code>
 <code>> str(tbl)
@@ Line 213: / Line 230: @@
 > url <- 'http://en.wikipedia.org/wiki/World_population'
 > tbls <- readHTMLTable(url)
+</code>
+The above not working for me. :(
+<code>library(httr)
+url <- 'http://en.wikipedia.org/wiki/World_population'
+tables <- GET(url)
+tables <- readHTMLTable(rawToChar(tables$content))
 </code>