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code/快速读写：大数据的导入与导出-练习提示.R

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+
+library(pacman)
+p_load(tidyverse,tidyfst)
+
+# 生成指定行数的数据框
+get_df = \(no_of_rows) {
+  tibble(
+    Logical = sample(c(TRUE, FALSE, NA), prob = c(0.85, 0.1, 0.05), no_of_rows, replace = TRUE),
+    Integer = sample(1L:100L, no_of_rows, replace = TRUE),
+    Double = sample(sample(1:10000, 20) / 100, no_of_rows, replace = TRUE),
+    Factor = as.factor(sample(LETTERS, no_of_rows, replace = TRUE))
+  )
+}
+
+pst(
+  map(10^(6:8),get_df) -> all_data
+)
+
+# 观察数据大小
+walk(all_data,object_size)
+
+# walk2(str_c("df",6:8),all_data,~assign(x = .x,value = .y,envir = .GlobalEnv))
+
+# 读写函数
+p_load(fst,data.table,arrow,qs,readxl,writexl)
+
+# csv
+fread();fwrite() 
+read_csv();write_csv() 
+
+# xlsx
+readxl::read_xlsx();writexl::write_xlsx() 
+
+# rds
+readRDS();saveRDS()
+read_rds();write_rds()
+
+# fst
+read_fst();write_fst()
+
+# arrow
+read_parquet();write_parquet()
+read_feather();write_feather()
+
+# qs
+qload();qsave()
+
+# 读写时间
+bench::mark()
+
+# 文件体积
+fs::file_size()
+
+
+
+
+
+
+