Updating 'help_r.R' script

README.org

@@ -1,9 +1,7 @@
 * R_info
 
-Some resources to learn about R
-
+Some resources to learn about R.
 The R Project for Statistical Computing is a free environment for statistical computing and graphics.
-
 More information about R: https://www.r-project.org/
 
 ** Index

doc/courses_other.org

@@ -39,12 +39,12 @@
 
  * http://sillasgonzaga.com/material/curso_visualizacao/
 
-** *Curso introdução à linguagem R para ecologia :pt:*
+** Curso introdução à linguagem R para ecologia :pt:
 
  * Alexandre Adalardo de Oliveira
    * http://ecor.ib.usp.br/doku.php
 
-** Blog curso sobre R e PostgreSQL
+** Blog curso sobre R e PostgreSQL :pt:
 
  * Curso Consudata
    * http://rpg.consudata.com.br/

doc/resources_in_R.org

@@ -1,5 +1,16 @@
 * Resources to learn R within R
 
+There are many sources to learn about R. As any GNU project, the manuals and info
+documentation are the first and most important source to be used.
+
+Most of the times it is not necessary to open a question in a community nor open
+a browser to search in the web. Most of the times the answer is on your own
+copy of the manual.
+
+R and all the packages have extensive documentation and there are also packages
+that can be used to learn R within R.
+
+
 ** Package swirl
 
  * https://swirlstats.com/
@@ -23,4 +34,36 @@ the name of the package as argument:
   vignette(package = "data.table")
 #+end_example
 
+*** Find R documentation from emacs
+
+If you use R in emacs, you can also the manuals can also be accessed using
+'info' program, typing:
+
+: C-h i
+
+Please note that "C" means "CTRL" key.
+
+Then use 'ALT' + 'm' and write the initial words of the manual you are looking
+for:
+
+: M m R
+
+*** Find R documentation from a shell in GNU-linux systems
+
+All the R manual can be accesed from a shell using the command "man":
+
+#+begin_example sh
+  man R
+#+end_example
+
+Typing in terminal 'info -f' followed by the name of each section will display
+manual in "info" version:
+
+ * info -f R-intro
+ * info -f R-data
+ * info -f R-exts
+ * info -f R-FAQ
+ * info -f R-lang
+ * info -f R-ints
+
 Check the [[../script/help_r.R][script]] to see additional resources.

script/help_r.R

@@ -12,22 +12,33 @@
 #'    highlight: zenburn
 #' ---
 
-#' remove objects
+#' removing objects
 #'
-objects()
 
 rm(list = ls())
 
-#' Libraries
-
 #' ## Common ways of getting help when working with R
 #'
-#' Within R use the "?" question symbol before any command and run
+
+#' ## Find the formal arguments in a function
 #'
-?dput
+formalArgs(help)
+
+formalArgs(table)
 
-#' Use "help", "help.search" or "apropos" when need search for some terms
+#' ### Use "help", "help.search" or "find" when need to search for some terms
+#'
+#' Use "help.start" to view all R documentation
+help.start()
+
+#' Within R use the "?" question symbol before any command and run the code
+#' to get help on that function.
+#'
+#' Getting help with "dput()" and "Compare" functions:
 #'
+?dput
+
+?Compare
 
 #' Ask about control-flow constructs in R
 help("if")
@@ -38,22 +49,34 @@ help("[[")
 #' Help on "Quotes"
 help(Quotes)
 
+#' Use "help.search" to find functions matching any word
 help.search("download file")
 
-#' Find the formal arguments in a function
-formalArgs(help)
-
-formalArgs(table)
-
-#' "find" can be used to know which package contains a function
+#' ### "find" can be used to know which package contains a function
 
 find("table")
 
-find("count")#' this will return nothing, because the package should be loaded
+#' This will return nothing, because the package should be loaded in the session
+#' in order to "find" the function
 
+find("count")
+
+#' Then, after loading the package that contains the function it should run
+#' without any problem
 library(dplyr)
 
-#' "apropos" give the name of objects containing the characters passed to the function
+find("count")
+
+#' Unload a package from the environment
+#'
+detach("package:dplyr", unload = TRUE)
+
+#' ### "apropos" gives the name of objects containing the characters passed to
+#' the function.
+#'
+#' Remember that wihin R (almost) everything that exist is an object and everything
+#' that happens is a function. Thus apropos will find any object (including
+#' functions) within the session matching the word.
 
 count_testing <- c(1,2)
 
@@ -61,35 +84,50 @@ apropos("count")
 
 #' ## Examples and demostration of functions
 #'
+#' ### Examples included in packages documentation
+#'
+#' The function to show examples of any functions is called "example":
 example(glm)
 
-library(lubridate)
-example(ymd)
+#' To extract examples of any function, the package containing the function should
+#' be loaded in the session:
+#'
+library(data.table)
 
-example(Compare)
+#' Check some examples on how to use the function ".N" in the "data.table" package
+example(.N)
 
 library(dplyr)
 example(case_when)
 
+#' ### Using "demo()"
 demo(graphics)
 
-#' Use "help.start" to view all R documentation
-help.start()
-
 #' ## Searching in packages
 #'
 #' Obtain help in packages
 
 library(help = data.table)
 
+#' ## Finding objects within a package and checking documentation
 
-#' Finding objects within a package
-
+#' ### Finding objects
+#'
+#' Here we use "grep" to look for objects within the package "data.table".
+#' The function "search" is applied to look for R objects, thus the function
+#' will return the names of every function within the package
+#'
 library(data.table)
 
 objects(grep("data.table", search()))
 
-#' List vignettes in a package
+#' Take a look to the objects in the base package:
+#'
+obase <- objects(grep("base", search()))
+
+head(obase, n=10)
+
+#' ### List vignettes in a package
 
 vignette(package = "data.table")
 
@@ -97,17 +135,8 @@ browseVignettes("data.table")
 
 vignette("datatable-faq")
 
-#' Edit dataframe using R data editor
-#'
-
-carros <- cars
-
-fix(carros)
-
-carros
+#' End
 
-#' Unload a package from the environment
+#' You can export this document as html using "rmarkdown":
 #'
-#' detach("package:data.table", unload = TRUE)
-
-#' End
+#' rmarkdown::render("./help_r.R")