R Programming is a language and environment for statistical computing and graphics and provides a rich set of libraries (packages) that extend its functionality. Often, it becomes necessary to explore the contents of these libraries to understand what functions, datasets, and other objects they offer. This article will discuss how to interactively explore the contents of a library in the R Programming Language.

What is Library in R?

In R a library (often referred to as a package) is a collection of functions, datasets, and other pre-written code that extends the capabilities of base R. Base R refers to the built-in packages in the R programming language. Let’s see how libraries extend the capabilities of base R:

Why Explore Library Contents?

Following are some of the reasons to explore library content in R:

• Discover New Tools: R has a massive collection of packages, each with its own set of functionalities. Exploring libraries helps in building an understanding of how they work and discovering various functions and datasets you might not have known about. This can be very helpful for data analysis, visualization, and modeling in a better way.
• Enhance Efficiency: Using well-developed libraries can enhance efficiency and productivity. By using libraries, we do not have to write code from scratch; we can make use of existing functions and methods to complete the desired task. This helps in maintaining focus on analysis and interpretation of results rather than on coding details.
• Reproducibility and Collaboration: Libraries often come with comprehensive documentation and standardized functions, making your code more readable and easier to reproduce. If one writes code from scratch instead of using libraries, colleagues have to focus on code details to understand what functions are used, which takes more time.
• Staying Current with Advances: As R is open source, many developers contribute to advancing and improving libraries, and new techniques and methodologies are constantly being developed.

Now we are discuss some main function of Getting the Contents of a Library Interactively in R Programming Language.

1. Loading a Library

Before exploring the contents of a library, you need to load it into your R session using the library function. If the library is not installed, you can install it using the install.packages function.

# Install a package if it's not already installed
# install.packages("dplyr")

# Load the library
library(dplyr)

2. Listing Objects in a Library

To list all objects (functions, datasets, etc.) provided by a library, you can use the ls function combined with the package argument.

# List all objects in the 'dplyr' package
ls("package:dplyr")

Output:

  [1] "%>%"                   "across"                "add_count"            
  [4] "add_count_"            "add_row"               "add_rownames"         
  [7] "add_tally"             "add_tally_"            "all_equal"            
 [10] "all_of"                "all_vars"              "anti_join"            
 [13] "any_of"                "any_vars"              "arrange"              
 [16] "arrange_"              "arrange_all"           "arrange_at"           
 [19] "arrange_if"            "as.tbl"                "as_data_frame"        
 [22] "as_label"              "as_tibble"             "auto_copy"            
 [25] "band_instruments"      "band_instruments2"     "band_members"         
 [28] "bench_tbls"            "between"               "bind_cols"            
 [31] "bind_rows"             "c_across"              "case_match"           
 [34] "case_when"             "changes"               "check_dbplyr"         
 [37] "coalesce"              "collapse"              "collect"              
 [40] "combine"               "common_by"             "compare_tbls"         
 [43] "compare_tbls2"         "compute"               "consecutive_id"       
 [46] "contains"              "copy_to"               "count"                
 [49] "count_"                "cross_join"            "cumall"               
 [52] "cumany"                "cume_dist"             "cummean"              
 [55] "cur_column"            "cur_data"              "cur_data_all"         
 [58] "cur_group"             "cur_group_id"          "cur_group_rows"       
 [61] "current_vars"          "data_frame"            "db_analyze"           
 [64] "db_begin"              "db_commit"             "db_create_index"      
 [67] "db_create_indexes"     "db_create_table"       "db_data_type"         
 [70] "db_desc"               "db_drop_table"         "db_explain"           
 [73] "db_has_table"          "db_insert_into"        "db_list_tables"       
 [76] "db_query_fields"       "db_query_rows"         "db_rollback"          
 [79] "db_save_query"         "db_write_table"        "dense_rank"           
 [82] "desc"                  "dim_desc"              "distinct"             
 [85] "distinct_"             "distinct_all"          "distinct_at"          
 [88] "distinct_if"           "distinct_prepare"      "do"                   
 [91] "do_"                   "dplyr_col_modify"      "dplyr_reconstruct"    
 [94] "dplyr_row_slice"       "ends_with"             "enexpr"               
 [97] "enexprs"               "enquo"                 "enquos"               
[100] "ensym"                 "ensyms"                "eval_tbls"            
[103] "eval_tbls2"            "everything"            "explain"              
[106] "expr"                  "failwith"              "filter"               
[109] "filter_"               "filter_all"            "filter_at"            
[112] "filter_if"             "first"                 "full_join"            
[115] "funs"                  "funs_"                 "glimpse"              
[118] "group_by"              "group_by_"             "group_by_all"         
[121] "group_by_at"           "group_by_drop_default" "group_by_if"          
[124] "group_by_prepare"      "group_cols"            "group_data"           
[127] "group_indices"         "group_indices_"        "group_keys"           
[130] "group_map"             "group_modify"          "group_nest"           
[133] "group_rows"            "group_size"            "group_split"          
[136] "group_trim"            "group_vars"            "group_walk"           
[139] "grouped_df"            "groups"                "id"                   
[142] "ident"                 "if_all"                "if_any"               
[145] "if_else"               "inner_join"            "intersect"            
[148] "is.grouped_df"         "is.src"                "is.tbl"               
[151] "is_grouped_df"         "join_by"               "lag"                  
[154] "last"                  "last_col"              "last_dplyr_warnings"  
[157] "lead"                  "left_join"             "location"             
[160] "lst"                   "make_tbl"              "matches"              
[163] "min_rank"              "mutate"                "mutate_"              
[166] "mutate_all"            "mutate_at"             "mutate_each"          
[169] "mutate_each_"          "mutate_if"             "n"                    
[172] "n_distinct"            "n_groups"              "na_if"                
[175] "near"                  "nest_by"               "nest_join"            
[178] "new_grouped_df"        "new_rowwise_df"        "nth"                  
[181] "ntile"                 "num_range"             "one_of"               
[184] "order_by"              "percent_rank"          "pick"                 
[187] "progress_estimated"    "pull"                  "quo"                  
[190] "quo_name"              "quos"                  "recode"               
[193] "recode_factor"         "reframe"               "relocate"             
[196] "rename"                "rename_"               "rename_all"           
[199] "rename_at"             "rename_if"             "rename_vars"          
[202] "rename_vars_"          "rename_with"           "right_join"           
[205] "row_number"            "rows_append"           "rows_delete"          
[208] "rows_insert"           "rows_patch"            "rows_update"          
[211] "rows_upsert"           "rowwise"               "same_src"             
[214] "sample_frac"           "sample_n"              "select"               
[217] "select_"               "select_all"            "select_at"            
[220] "select_if"             "select_var"            "select_vars"          
[223] "select_vars_"          "semi_join"             "setdiff"              
[226] "setequal"              "show_query"            "slice"                
[229] "slice_"                "slice_head"            "slice_max"            
[232] "slice_min"             "slice_sample"          "slice_tail"           
[235] "sql"                   "sql_escape_ident"      "sql_escape_string"    
[238] "sql_join"              "sql_select"            "sql_semi_join"        
[241] "sql_set_op"            "sql_subquery"          "sql_translate_env"    
[244] "src"                   "src_df"                "src_local"            
[247] "src_mysql"             "src_postgres"          "src_sqlite"           
[250] "src_tbls"              "starts_with"           "starwars"             
[253] "storms"                "summarise"             "summarise_"           
[256] "summarise_all"         "summarise_at"          "summarise_each"       
[259] "summarise_each_"       "summarise_if"          "summarize"            
[262] "summarize_"            "summarize_all"         "summarize_at"         
[265] "summarize_each"        "summarize_each_"       "summarize_if"         
[268] "sym"                   "symdiff"               "syms"                 
[271] "tally"                 "tally_"                "tbl"                  
[274] "tbl_df"                "tbl_nongroup_vars"     "tbl_ptype"            
[277] "tbl_vars"              "tibble"                "top_frac"             
[280] "top_n"                 "transmute"             "transmute_"           
[283] "transmute_all"         "transmute_at"          "transmute_if"         
[286] "tribble"               "type_sum"              "ungroup"              
[289] "union"                 "union_all"             "validate_grouped_df"  
[292] "validate_rowwise_df"   "vars"                  "where"                
[295] "with_groups"           "with_order"            "wrap_dbplyr_obj" 

3. Getting Detailed Information

To get detailed information about a specific function or dataset, use the help or ? command. This will open the help page for the specified object.

# Get help on the 'filter' function from the 'dplyr' package
help("filter", package = "dplyr")
# or equivalently
?dplyr::filter

Output:

Getting the Contents of a Library Interactively in R

4. Exploring Vignettes

Many R packages come with vignettes, which are long-form documentation that includes examples and explanations. You can list and view vignettes using the following commands:

# List vignettes for the 'dplyr' package
vignette(package = "dplyr")

# View a specific vignette
vignette("dplyr")

Output:

Vignettes in package ‘dplyr’:

colwise               Column-wise operations (source, html)
base                  dplyr <-> base R (source, html)
grouping              Grouped data (source, html)
dplyr                 Introduction to dplyr (source, html)
programming           Programming with dplyr (source, html)
rowwise               Row-wise operations (source, html)
two-table             Two-table verbs (source, html)
in-packages           Using dplyr in packages (source, html)
window-functions      Window functions (source, html)

Conclusion

Exploring the contents of a library interactively in R is essential for effectively utilizing the rich set of functions and datasets available. By using functions like ls, help, vignette, and ls.str, you can gain a comprehensive understanding of any R package. Additionally, leveraging interactive tools like RStudio can further enhance your ability to navigate and utilize libraries efficiently.