rrparallel

Unable to call create_cluster in multidplyr


I am able to load all the packages and able to see the no of cores available as well but I am getting
Error in create_cluster(4) : could not find function "create_cluster"

    library(multidplyr)
    library(dplyr)
    library(parallel)
    numCores <- detectCores()
    start.time <- Sys.time() 
    cluster <- create_cluster(4)

Solution

  • As you can view all the functions presented in a package by using use lsf.str() you see that the function create_cluster() isnt included. Running:

    ls("package:multidplyr")
    ls("package:dplyr")
    ls("package:parallel")
    

    gives you a list of all the functions. Multiplyr:

     [1] "%>%"                      "cluster_assign"          
     [3] "cluster_assign_each"      "cluster_assign_partition"
     [5] "cluster_call"             "cluster_copy"            
     [7] "cluster_library"          "cluster_rm"              
     [9] "cluster_send"             "default_cluster"         
    [11] "new_cluster"              "partition"               
    [13] "party_df"                
    

    dplyr:

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

    Parallel:

     [1] "clusterApply"        "clusterApplyLB"      "clusterCall"        
     [4] "clusterEvalQ"        "clusterExport"       "clusterMap"         
     [7] "clusterSetRNGStream" "clusterSplit"        "detectCores"        
    [10] "getDefaultCluster"   "makeCluster"         "makeForkCluster"    
    [13] "makePSOCKcluster"    "mclapply"            "mcMap"              
    [16] "mcmapply"            "nextRNGStream"       "nextRNGSubStream"   
    [19] "parApply"            "parCapply"           "parLapply"          
    [22] "parLapplyLB"         "parRapply"           "parSapply"          
    [25] "parSapplyLB"         "pvec"                "setDefaultCluster"  
    [28] "splitIndices"        "stopCluster"       
    

    Does that information help you?