https://stackoverflow.com/questions/15921886
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RussianMy question is in fact a duplicate of at least:
1) Stop Excel from automatically converting certain text values to dates
2) Excel: Default to TEXT rather than GENERAL when opening a .csv file
The possible solutions for Excel are to 1) either writing the fields with special double quotes like "May 16, 2011" as "=""May 16, 2011""" or 2) importing the csv/tsv file with the external data wizard and then selecting manually which columns you want to read as TEXT and not GENERAL (which could convert fields to dates)
As for my use case, I was only using Excel to remove some columns. None of the solutions was appealing to me because I wouldn't like to rewrite the tsv files with special quotes and because I had hundreds of columns and I didn't want to select each manually to be read as TEXT.
Therefore I wrote a scala script to filter tsv files by column names:
package com.jmcejuela.ml
import java.io.InputStream
import java.io.Writer
import scala.io.Codec
import scala.io.Source
import Table._
/**
* Class to represent tables with a fixed size of columns. All rows have the same columns.
*/
class Table(val rows: Seq[Row]) {
lazy val numDiffColumns = rows.foldLeft(Set[Int]())((set, row) => set + row.size)
def toTSV(out: Writer) {
if (rows.isEmpty) out.write(TableEmpty.toString)
else {
out.write(writeLineTSV(rows.head.map(_.name))) //header
rows.foreach(r => out.write(writeLineTSV(r.map(_.value))))
out.close
}
}
/**
* Get a Table with only the given columns.
*/
def filterColumnsByName(columnNames: Set[String]): Table = {
val existingNames = rows.head.map(_.name).toSet
assert(columnNames.forall(n => existingNames.contains(n)), "You want to include column names that do not exist")
new Table(rows.map { row => row.filter(col => columnNames.contains(col.name)) })
}
}
object TableEmpty extends Table(Seq.empty) {
override def toString = "Table(Empty)"
}
object Table {
def apply(rows: Row*) = new Table(rows)
type Row = Array[Column]
/**
* Column representation. Note that each column has a name and a value. Since the class Table
* is a sequence of rows which are a size-fixed array of columns, the name field is redundant
* for Table. However, this column representation could be used in the future to support
* schemata-less tables.
*/
case class Column(name: String, value: String)
private def parseLineTSV(line: String) = line.split("\t")
private def writeLineTSV(line: Seq[String]) = line.mkString("", "\t", "\n")
/**
* It is assumed that the first row gives the names to the columns
*/
def fromTSV(in: InputStream)(implicit encoding: Codec = Codec.UTF8): Table = {
val linesIt = Source.fromInputStream(in).getLines
if (linesIt.isEmpty) TableEmpty
else {
val columnNames = parseLineTSV(linesIt.next)
val padding = {
//add padding of empty columns-fields to lines that do not include last fields because they are empty
def infinite[A](x: A): Stream[A] = x #:: infinite(x)
infinite("")
}
val rows = linesIt.map { line =>
((0 until columnNames.size).zip(parseLineTSV(line) ++: padding).map { case (index, field) => Column(columnNames(index), field) }).toArray
}.toStream
new Table(rows)
}
}
}
