using System;

using System.Text.RegularExpressions;

public class Program

{

    public static void Main()

    {

        double replace = 1.1;

        String filter = "M15_Ch1_Shunt";

        String s = "SG_ M15_Ch1_Shunt : 0|16@1- (1.52592547,-2.4) [-25000|25000] \"mA\"  CSM_GmbH\nSG_ M15_Ch2_Shunt : 16|16@1- (1.52592547,4.3) [-25000|25000] \"mA\"  CSM_GmbH\nSG_ M15_Ch3_Shunt : 32|16@1- (1.52592547,0) [-25000|25000] \"mA\"  CSM_GmbH\nSG_ M15_Ch4_Shunt : 48|16@1- (1.52592547,3) [-25000|25000] \"mA\"  CSM_GmbH";

        Console.Write(Regex.Replace(s, @"^(SG_ "+filter+@"[^,]+,)(-?\d+\.\d+)(.+)", "${1}"+replace+"${3}" ));

    }

}