need to change regex for additional postfix criteria

Question

So i have this code:

Pattern pattern = Pattern.compile("\\d*(\\s\\d+\\.)*\\s*[-\\+\\*/\\$£]");

String input = "4.0 5.0 2.0 / + 7.0 - 11.0 34.0 2.0 / 3.0 / 1.0 * +";
Matcher matcher = pattern.matcher(input);
List<String> output = new ArrayList<>();
while (matcher.find()) {
    output.add(matcher.group());
}

When i was working on just parsing integers the regex was of course fine however i now need it to take into account that there can be a . to represent a floating point.

Wondering if someone can help me with adding this in

expected output should be :

4.0 5.0 2.0 / 
+ 
7.0 - 
11.0 34.0 2.0 /
3.0 / 
1.0 * 
+

Here you go, `"\\d+(?:\\.\\d+)?(\\s\\d+(?:\\.\\d+)?)*\\s*[-\\+\\*/\\$£]"` — Avinash Raj, Dec 22 '14 at 11:52
For this output you can just use `[\d\s.]*[\-+/*$£]`, or split by `[\-+/*$£]`. — Kobi, Dec 22 '14 at 11:53
Avinash Raj solution seems to work although i might as well be reading a long lost language as it makes no sense to me, however my unit tests seem to pass so, so far so good. thankyou, feel free to post as an answer so i can accept. Kobi will that persist the delimeter though ? — user1383163, Dec 22 '14 at 11:56

score 0 · Accepted Answer · answered Dec 22 '14 at 11:57

This would produce the output you want. The part next to the Logical OR | operator will matches the [-+*/$£] symbols from the remaining sub-string.

Pattern pattern = Pattern.compile("\\d+(?:\\.\\d+)?(\\s\\d+(?:\\.\\d+)?)*\\s*[-+*/$£]|[-+*/$£]");

String input = "4.0 5.0 2.0 / + 7.0 - 11.0 34.0 2.0 / 3.0 / 1.0 * +";
Matcher matcher = pattern.matcher(input);
ArrayList<String> output = new ArrayList<String>();
while (matcher.find()) {
    output.add(matcher.group());
}
for (String s: output)
{
    System.out.println(s);
}

Output:

4.0 5.0 2.0 /
+
7.0 -
11.0 34.0 2.0 /
3.0 /
1.0 *
+

need to change regex for additional postfix criteria

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