DiagrammeR (version 0.8.4)

add_nodes_from_table: Add nodes and attributes to graph from a table

Description

Add nodes and their attributes to an existing graph object from data in a CSV file or a data frame.

Usage

add_nodes_from_table(graph, table, set_type = NULL, select_cols = NULL, drop_cols = NULL, rename_attrs = NULL, id_col = NULL, type_col = NULL, label_col = NULL)

Arguments

graph

a graph object of class dgr_graph that is created using create_graph.

table

either a path to a CSV file, or, a data frame object.

set_type

an optional string to apply a type attribute to all nodes created from the table records.

select_cols

an optional character vector for specifying which columns in the table that should be imported as node attributes.

drop_cols

an optional character vector for dropping columns from the incoming data.

rename_attrs

an optional character for renaming node attributes.

id_col

an option to apply a column of data in the table as node ID values.

type_col

an option to apply a column of data in the table as type attribute values.

label_col

an option to apply a column of data in the table as label attribute values.

Value

a graph object of class dgr_graph.

Examples

## Not run: 
# library(magrittr)
# library(dplyr)
# 
# # Specify a path to a CSV file
# path_to_csv <-
#   system.file("examples/currencies.csv",
#               package = "DiagrammeR")
# 
# # To add nodes from a CSV file, call the
# # `add_nodes_from_table()` function; new node ID
# # values will be created as a monotonically-
# # increasing values from 1
# graph_1 <-
#   create_graph() %>%
#   add_nodes_from_table(path_to_csv)
# 
# # View the graph's internal node data frame (ndf)
# # with `get_node_df()` and dplyr's `as.tbl()`
# graph_1 %>% get_node_df %>% as.tbl
# #> Source: local data frame [171 x 7]
# #>
# #>    nodes  type label iso_4217_code curr_number
# #>    (chr) (chr) (chr)         (chr)       (chr)
# #> 1      1                       AED         784
# #> 2      2                       AFN         971
# #> 3      3                       ALL           8
# #> 4      4                       AMD          51
# #> 5      5                       ANG         532
# #> 6      6                       AOA         973
# #> 7      7                       ARS          32
# #> 8      8                       AUD          36
# #> 9      9                       AWG         533
# #> 10    10                       AZN         944
# #> ..   ...   ...   ...           ...         ...
# #> Variables not shown: exponent (chr)
# #>   currency_name (chr)
# 
# # If you would like to assign any of the table's
# # columns as `type` or `label` attributes, this can
# # be done with the `type_col` and `label_col`
# # arguments; to set a static `type` attribute for
# # all of the table records, use `set_type`
# graph_2 <-
#   create_graph() %>%
#   add_nodes_from_table(
#     path_to_csv,
#     set_type = "currency",
#     label_col = "iso_4217_code")
# 
# # View the first 3 lines of the graph's internal ndf
# graph_2 %>% get_node_df %>% head(3) %>% as.tbl
# #> Source: local data frame [3 x 6]
# #>
# #>   nodes     type label curr_number exponent
# #>   (chr)    (chr) (chr)       (chr)    (chr)
# #> 1     1 currency   AED         784        2
# #> 2     2 currency   AFN         971        2
# #> 3     3 currency   ALL           8        2
# #> Variables not shown: currency_name (chr)
# 
# # Suppose you would like to not include certain
# # columns from the table in the resulting graph; you
# # can use the `drop_cols` argument to choose which
# # columns to not include as attributes in the graph
# graph_3 <-
#   create_graph() %>%
#   add_nodes_from_table(
#     path_to_csv,
#     set_type = "currency",
#     label_col = "iso_4217_code",
#     drop_cols = "exponent")
# 
# graph_3 %>% get_node_df %>% head(3) %>% as.tbl
# #> Source: local data frame [3 x 5]
# #>
# #>   nodes     type label curr_number
# #>   (chr)    (chr) (chr)       (chr)
# #> 1     1 currency   AED         784
# #> 2     2 currency   AFN         971
# #> 3     3 currency   ALL           8
# #> Variables not shown: currency_name (chr)
# ## End(Not run)