rsc3/doc-schelp/HelpSource/Classes/CSVFileReader.scrbl

76 lines
1.7 KiB
Racket

#lang scribble/manual
@(require (for-label racket))
@title{CSVFileReader}
file reader for comma separated data@section{related}
Classes/File
@section{categories}
Files
@section{description}
CSVFileReader reads comma-separated text files into 2D arrays line by line.
For tab delimited files use link::Classes/TabFileReader::. For semi-colon-delimited files use link::Classes/SemiColonFileReader::. For space-delimited files, or custom delimiters, use link::Classes/FileReader::.
@section{Examples}
@racketblock[
(
// write a test file:
f = File("CSVReadTest.sc", "w");
f.write(
"Some,comma,delimited,items, in line 1
and then, some more, with several commas,,,, in line 3
"
);
f.close;
)
// open file, read and put strings into array, close file.
x = CSVFileReader.read("CSVReadTest.sc").postcs;
// can skip empty lines:
x = CSVFileReader.read("CSVReadTest.sc", true).postcs;
// can skip blank entries caused by multiple commas:
x = CSVFileReader.read("CSVReadTest.sc", true, true).postcs;
// do file open/close by hand if you prefer:
f = File("CSVReadTest.sc", "r"); f.isOpen;
t = CSVFileReader(f);
t.read(true, true).postcs;
f.close;
(
// write a test file with numbers:
f = File("CSVReadTestNum.sc", "w");
(1..10).do { |n| f.write(n.asString ++ ","); };
f.close;
)
x = CSVFileReader.read("CSVReadTestNum.sc", true, true).postcs;
x.collect(_.collect(_.interpret)); // convert to numbers.
// or do it immediately:
x = CSVFileReader.readInterpret("CSVReadTestNum.sc").postcs;
(
// write a test file with several lines of numbers:
f = File("CSVReadTestNum.sc", "w");
(1..100).do { |n|
f.write(n.asString ++ if (n % 10 != 0, ",", Char.nl)); };
f.close;
)
x = CSVFileReader.readInterpret("CSVReadTestNum.sc", true, true).postln;
]