Question

我有一个层次非常深的JSON文件（例如https://raw.githubusercontent.com/APSIMInitiative/ApsimX/master/Models/Resources/Wheat.json）

# read data
library(jsonlite)
m <- read_json('https://raw.githubusercontent.com/APSIMInitiative/ApsimX/master/Models/Resources/Wheat.json')

我想找到一个名称==“ PotentialBranchingRate”的元素。

{
    "$type": "Models.Functions.PhaseLookup, Models",
     "Name": "PotentialBranchingRate",
     "Children": [...]
}

预期结果将返回"Name": "PotentialBranchingRate"的父节点。

List of 2
 $ $type: chr "Models.Functions.PhaseLookup, Models"
 $ Name : chr "PotentialBranchingRate"
 $ Children : list ...

我已经在包rlist和purrr中搜索了函数，但是找不到任何方法。

有解决此问题的建议吗？

Answer 1

library(data.tree)

x <- as.Node(m)

Traverse(x, filterFun = function(.) 
  identical(GetAttribute(., "Name"), "PotentialBranchingRate")
)
#> [[1]]
#>                               levelName
#> 1  2                                   
#> 2   °--Children                        
#> 3       ¦--1                           
#> 4       ¦   °--Children                
#> 5       ¦       °--1                   
#> 6       ¦           °--Children        
#> 7       ¦               °--1           
#> 8       ¦                   ¦--X       
#> 9       ¦                   ¦--Y       
#> 10      ¦                   °--Children
#> 11      °--2                           
#> 12          °--Children                
#> 13              °--1                   
#> 14                  °--Children        
#> 
#> [[2]]
#>              levelName
#> 1 1                   
#> 2  °--Children        
#> 3      °--1           
#> 4          ¦--X       
#> 5          ¦--Y       
#> 6          °--Children

res <- .Last.value
lapply(res, function(.) jsonlite::prettify(rjson::toJSON(as.list(.))))
#> [[1]]
#> {
#>     "$type": "Models.Functions.PhaseLookup, Models",
#>     "Enabled": true,
#>     "IncludeInDocumentation": true,
#>     "Name": "PotentialBranchingRate",
#>     "ReadOnly": false,
#>     "Children": {
#>         "1": {
#>             "$type": "Models.Functions.PhaseLookupValue, Models",
#>             ....
#>        
#> ....... (truncated output for clarity) 
#> 
#> [[2]]
#> {
#>     "$type": "Models.Functions.LinearInterpolationFunction, Models",
#>     "Enabled": true,
#>     "IncludeInDocumentation": true,
#>     "Name": "PotentialBranchingRate",
#>     "ReadOnly": false,
#>     "XProperty": "[Structure].LeafTipsAppeared",
#>     "Children": {
#>         "1": {
#>             "$type": "Models.Functions.XYPairs, Models",
#>             "Enabled": true,
#>             "IncludeInDocumentation": true,
#>             "Name": "XYPairs",
#>             "ReadOnly": false,
#>             "X": {
#>                 "1": 1,
#>                 "2": 2,
#>                 "3": 3,
#>                 "4": 4,
#>                 "5": 5,
#>                 "6": 6,
#>                 "7": 7,
#>                 "8": 8
#>             },
#>             "Y": {
#>                 "1": 0,
#>                 "2": 0,
#>                 "3": 1,
#>                 "4": 2,
#>                 "5": 4,
#>                 "6": 7,
#>                 "7": 12,
#>                 "8": 20
#>             },
#>             "Children": [
#> 
#>             ]
#>         }
#>     }
#> }
#>

^{由reprex package（v0.2.1）于2019-02-21创建}

Answer 2

library(curl)
library(jqr)

url <- paste0(
  'https://raw.githubusercontent.com/',
  'APSIMInitiative/ApsimX/master/Models/Resources/Wheat.json'
)

curl(url) %>% 
  jq('.. | select(.Name? == "PotentialBranchingRate")')
#> [
#>     {
#>         "$type": "Models.Functions.PhaseLookup, Models",
#>         "Name": "PotentialBranchingRate",
#>         "Children": [
#>             {
#>                 "$type": "Models.Functions.PhaseLookupValue, Models",
#>                 "Start": "Emergence",
#>                 "End": "TerminalSpikelet",
#>                 "Name": "Vegetative",
#>                 "Children": [
#>                     {
#>                         "$type": "Models.Functions.LinearInterpolationFunction, Models",
#>                         "XProperty": "[Structure].LeafTipsAppeared",
#>                         "Name": "PotentialBranchingRate",
#>                         "Children": [
#>                             {
#>                                 "$type": "Models.Functions.XYPairs, Models",
#>                                 "X": [
#>                                     1,
#>                                     2,
#>                                     3,
#>                                     4,
#>                                     5,
#>                                     6,
#>                                     7,
#>                                     8
#>                                 ],
#>                                 "Y": [
#>                                     0,
#>                                     0,
#>                                     1,
#>                                     2,
#>                                     4,
#>                                     7,
#>                                     12,
#>                                     20
#>                                 ],
#>                                 "Name": "XYPairs",
#>                                 "Children": [
#> 
#>                                 ],
#>                                 "IncludeInDocumentation": true,
#>                                 "Enabled": true,
#>                                 "ReadOnly": false
#>                             }
#>                         ],
#>                         "IncludeInDocumentation": true,
#>                         "Enabled": true,
#>                         "ReadOnly": false
#>                     }
#>                 ],
#>                 "IncludeInDocumentation": true,
#>                 "Enabled": true,
#>                 "ReadOnly": false
#>             },
#>             {
#>                 "$type": "Models.Functions.PhaseLookupValue, Models",
#>                 "Start": "TerminalSpikelet",
#>                 "End": "HarvestRipe",
#>                 "Name": "Reproductive",
#>                 "Children": [
#>                     {
#>                         "$type": "Models.Functions.Constant, Models",
#>                         "FixedValue": 0,
#>                         "Units": null,
#>                         "Name": "Zero",
#>                         "Children": [
#> 
#>                         ],
#>                         "IncludeInDocumentation": true,
#>                         "Enabled": true,
#>                         "ReadOnly": false
#>                     }
#>                 ],
#>                 "IncludeInDocumentation": true,
#>                 "Enabled": true,
#>                 "ReadOnly": false
#>             }
#>         ],
#>         "IncludeInDocumentation": true,
#>         "Enabled": true,
#>         "ReadOnly": false
#>     },
#>     {
#>         "$type": "Models.Functions.LinearInterpolationFunction, Models",
#>         "XProperty": "[Structure].LeafTipsAppeared",
#>         "Name": "PotentialBranchingRate",
#>         "Children": [
#>             {
#>                 "$type": "Models.Functions.XYPairs, Models",
#>                 "X": [
#>                     1,
#>                     2,
#>                     3,
#>                     4,
#>                     5,
#>                     6,
#>                     7,
#>                     8
#>                 ],
#>                 "Y": [
#>                     0,
#>                     0,
#>                     1,
#>                     2,
#>                     4,
#>                     7,
#>                     12,
#>                     20
#>                 ],
#>                 "Name": "XYPairs",
#>                 "Children": [
#> 
#>                 ],
#>                 "IncludeInDocumentation": true,
#>                 "Enabled": true,
#>                 "ReadOnly": false
#>             }
#>         ],
#>         "IncludeInDocumentation": true,
#>         "Enabled": true,
#>         "ReadOnly": false
#>     }
#> ]

^{由reprex package（v0.2.1）于2019-02-21创建}

使用purrr或rlist

2 个答案: