String
toCsv(ArrayList columnVectors) to Csv
StringBuilder sb = new StringBuilder();
int n = columnVectors.size();
int m = columnVectors.get(0).length;
for (int i = 0; i < m; i++) {
for (int j = 0; j < n; j++) {
sb.append(columnVectors.get(j)[i]);
if (j < n - 1) {
sb.append(",");
...
String
ToCSV(ArrayList vals) To CSV
String res = "";
for (Integer i = 0; i < vals.size(); ++i) {
if (i > 0) {
res += ",";
res += vals.get(i).toString();
return res;
...
String
toCsvRow(ArrayList csvRow) to Csv Row
StringBuilder csvStringBuilder = new StringBuilder();
makeCsvRow(csvRow, csvStringBuilder);
return csvStringBuilder.toString();