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@apwan
Last active September 9, 2018 13:29
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js version read_csv (mimic python version)
const fs = typeof require != 'undefined'? require('fs'): {};
function catFile(path){
return fs.readFileSync(path).toString()
}
function CSVToArray(strData, strDelimiter) {
// Check to see if the delimiter is defined. If not,
// then default to COMMA.
strDelimiter = (strDelimiter || ",");
// Create a regular expression to parse the CSV values.
var objPattern = new RegExp(
(
// Delimiters.
"(\\" + strDelimiter + "|\\r?\\n|\\r|^)" +
// Quoted fields.
"(?:\"([^\"]*(?:\"\"[^\"]*)*)\"|" +
// Standard fields.
"([^\"\\" + strDelimiter + "\\r\\n]*))"
),
"gi"
);
// Create an array to hold our data. Give the array
// a default empty first row.
var arrData = [
[]
];
// Create an array to hold our individual pattern
// matching groups.
var arrMatches = null;
// Keep looping over the regular expression matches
// until we can no longer find a match.
while (arrMatches = objPattern.exec(strData)) {
// Get the delimiter that was found.
var strMatchedDelimiter = arrMatches[1];
// Check to see if the given delimiter has a length
// (is not the start of string) and if it matches
// field delimiter. If id does not, then we know
// that this delimiter is a row delimiter.
if (
strMatchedDelimiter.length &&
(strMatchedDelimiter != strDelimiter)
) {
// Since we have reached a new row of data,
// add an empty row to our data array.
arrData.push([]);
}
// Now that we have our delimiter out of the way,
// let's check to see which kind of value we
// captured (quoted or unquoted).
if (arrMatches[2]) {
// We found a quoted value. When we capture
// this value, unescape any double quotes.
var strMatchedValue = arrMatches[2].replace(
new RegExp("\"\"", "g"),
"\""
);
} else {
// We found a non-quoted value.
var strMatchedValue = arrMatches[3];
}
// Now that we have our value string, let's add
// it to the data array.
arrData[arrData.length - 1].push(strMatchedValue);
}
return arrData;
}
function read_csv(path){
var csv_str = catFile(path);
return CSVToArray(csv_str);
}
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