read_from_table_file {disprose}

Read table file

Description

Read table file and selects the required rows and columns.

Usage

read_from_table_file(
  file,
  choose.columns = FALSE,
  column.names,
  select = FALSE,
  select.column.name,
  select.val,
  unique = FALSE,
  sep = ";",
  header = TRUE
)

Arguments

file

character; file name and path

choose.columns

logical; return chosen columns only

column.names

character; vector of name of columns that are chosen to be returned

select

logical; return only rows that contain selected values in one column

select.column.name

character; name of column that contains selected values

select.val

vector of values that define rows that should be returned

unique

logical; delete duplicated rows

sep

character; the field separator character

header

logical; files contain the names of the variables as its first line

Details

This function reads table files and returns data frame with selected rows (only rows with specified values) and columns. Also duplicated rows may be deleted.

column.names and select.column.name must be exact column names as in data frame.

Value

Data frame with file content, optionally trimmed.

Author(s)

Elena N. Filatova

Examples

mydata <- data.frame (N = 1:10, letter = c(rep ("A", 5), rep ("B", 4), "C"),
                   num = c(1, rep(1:4, 2), 5))
t1<-tempfile()
write.table (mydata, t1, sep = ";")
read_from_table_file (file = t1)
read_from_table_file (file = t1, select = TRUE, select.column.name = "letter",
                     select.val = c("A", "C"))
read_from_table_file (file = t1, select = TRUE, select.column.name = "letter",
                     select.val = c("A", "C"), unique=TRUE, choose.columns = TRUE,
                     column.names = c("letter", "num"))
read_from_table_file (file = t1, select = TRUE, select.column.name = "letter",
                     select.val = c("A", "C"), unique = TRUE, choose.columns = TRUE,
                     column.names = c("N", "num"))
read_from_table_file (file = t1, select = TRUE, select.column.name = "letter",
                     select.val = c("A", "C"), unique = TRUE, choose.columns = TRUE,
                     column.names = c("letter", "N"))
file.remove (t1)