Is there a way to loop inside the element of a list of list in R?-CodePudding

I'm trying to loop inside a list of lists and to bind the results into a single data frame. The first part of my code works perfectly. However, when I try to loop from the resulting list (prueba) and to make one single data frame I do not have the desired output.

First part (reproducible example):

library(jsonlite)
library(httr)

lista <- c("BNBBTC","ETHBTC")
prueba <- list()
for (i in lista) {
  prueba[[i]] <- GET(paste0("https://api1.binance.com/api/v3/ticker/24hr?symbol=",i))
}

As for the second part, I know what I want is the aux_final data frame. However, I don't know how to loop without using the $ symbol.

aux <- fromJSON(rawToChar(prueba$ETHBTC$content))
aux <- data.frame(aux)

aux_2 <- fromJSON(rawToChar(prueba$BNBBTC$content))
aux_2 <- data.frame(aux_2)

aux_final <- bind_rows(aux,aux_2)

I want to loop the name of the coin "ETHBTC" or "BNBBTC" in this case and to have a resulting data frame like aux_final.

CodePudding user response：

You can loop in similar way

library(dplyr)

aux_final <- data.frame()
for (i in prueba){
  aux <- i[["content"]] %>% rawToChar %>% fromJSON %>% data.frame
  aux_final <- bind_rows(aux_final, aux)
}
aux_final

  symbol priceChange priceChangePercent weightedAvgPrice prevClosePrice  lastPrice    lastQty   bidPrice      bidQty   askPrice
1 ETHBTC  0.00062600              0.892       0.07026676     0.07014400 0.07077000 0.00990000 0.07077400  2.57850000 0.07077500
2 BNBBTC  0.00038000              4.428       0.00873508     0.00858200 0.00896200 0.53600000 0.00896100 44.73800000 0.00896200
      askQty  openPrice  highPrice   lowPrice          volume   quoteVolume     openTime    closeTime   firstId    lastId  count
1 1.00280000 0.07014400 0.07140000 0.06913300  76608.18500000 5383.00905379 1.635728e 12 1.635815e 12 306316825 306518132 201308
2 3.68300000 0.00858200 0.00905300 0.00843900 212858.68100000 1859.33793552 1.635728e 12 1.635815e 12 165844663 166011284 166622

CodePudding user response：

One way using lapply and glue:

library(jsonlite)
library(httr)
library(glue)
library(magrittr)

lista <- c("BNBBTC","ETHBTC")

aux_final <- lapply(lista, function(x){
  'https://api1.binance.com/api/v3/ticker/24hr?symbol={x}' %>% glue %>% GET %>% {.$content} %>% 
    rawToChar %>% fromJSON %>% data.frame
}) %>% do.call(rbind,.)