I have a string String a = "(3e4+2e2)sin(30)"; and i want to show it as a = "(3e4+2e2)*sin(30)";
I am not able to write a regular expression for this.
6 Answers
Try this replaceAll:
a = a.replaceAll("\) *(\\w+)", ")*$1");
4 Comments
Azfaar kabir Siddiqui
can you explain it a bit please why we use \\w+ and what is $1 and *(\\w+)
anubhava
\\w+ to match any word after ) and $1 is the back reference of that word (captured group #1) in the replacement string.Azfaar kabir Siddiqui
*(\\w+) and why you put closure after some space ?
anubhava
Round parentheses are used to capture the enclosed pattern in a captured group.
You can go with this
String func = "sin";// or any function you want like cos.
String a = "(3e4+2e2)sin(30)";
a = a.replaceAll("[)]" + func, ")*siz");
System.out.println(a);
3 Comments
Azfaar kabir Siddiqui
and what if i have a String a = "(3e4+2e2)cos(30)"; i want to a have regular expression for all the characters not just sin or cos please help
Salah
You need to store your function in a variable, then do the
replaceAll. see the updates in my answer.Azfaar kabir Siddiqui
i want only ) will change with )* not any character after and only those ) which are before any character or digit
this should work
a = a.replaceAll("\\)(\\s)*([^*+/-])", ") * $2");
Comments
String input = "(3e4+2e2)sin(30)".replaceAll("(\\(.+?\\))(.+)", "$1*$2"); //(3e4+2e2)*sin(30)
Comments
Assuming the characters within the first parenthesis will always be in similar pattern, you can split this string into two at the position where you would like to insert the character and then form the final string by appending the first half of the string, new character and second half of the string.
string a = "(3e4+2e2)sin(30)";
string[] splitArray1 = Regex.Split(a, @"^\(\w+[+]\w+\)");
string[] splitArray2 = Regex.Split(a, @"\w+\([0-9]+\)$");
string updatedInput = splitArray2[0] + "*" + splitArray1[1];
Console.WriteLine("Input = {0} Output = {1}", a, updatedInput);
Comments
I did not try but the following should work
String a = "(3e4+2e2)sin(30)";
a = a.replaceAll("[)](\\w+)", ")*$1");
System.out.println(a);
a = a.replaceAll("\)sin", ")*sin");