diff --git a/math.go b/math.go
index d38bd98..3643f48 100644
--- a/math.go
+++ b/math.go
@@ -14,7 +14,17 @@ func Calc(math string) (float64, error) {
 	if err := check(math); err != nil {
 		return 0, err
 	}
-	return calc(math)
+	result,err:=calc(math)
+	if err!=nil {
+		return 0,err
+	}
+	return floatRound(result,15),nil
+}
+
+func floatRound(f float64, n int) float64 {
+	format := "%." + strconv.Itoa(n) + "f"
+	res, _ := strconv.ParseFloat(fmt.Sprintf(format, f), 64)
+	return res
 }
 
 func check(math string) error {
@@ -37,11 +47,12 @@ func check(math string) error {
 				if string([]rune{v}) != "+" && string([]rune{v}) != "-" {
 					return fmt.Errorf("err at position %d.Reason is sign %s not correct", k, string([]rune{v}))
 				}
-				signReady = false
 			} else {
 				signReady = true
+				continue
 			}
 		}
+		signReady = false
 	}
 	if bracketSum != 0 {
 		return fmt.Errorf("Error:right bracket is not equal as left bracket")
@@ -188,16 +199,16 @@ func calcPool(numPool []float64, operPool []string) (float64, error) {
 func calcSigFloat(floatA float64, b string, floatC float64) (float64, error) {
 	switch b {
 	case "+":
-		return floatA + floatC, nil
+		return floatRound(floatA + floatC,15), nil
 	case "-":
-		return floatA - floatC, nil
+		return floatRound(floatA - floatC,15), nil
 	case "*":
-		return floatA * floatC, nil
+		return floatRound(floatA * floatC,15), nil
 	case "/":
 		if floatC == 0 {
 			return 0, errors.New("Divisor cannot be 0")
 		}
-		return floatA / floatC, nil
+		return floatRound(floatA / floatC,15), nil
 	case "^":
 		return math.Pow(floatA, floatC), nil
 	}
diff --git a/sysconf/sysconf.go b/sysconf/sysconf.go
index 5020e99..bc015c9 100644
--- a/sysconf/sysconf.go
+++ b/sysconf/sysconf.go
@@ -47,6 +47,18 @@ type SysNode struct {
 	lock    sync.RWMutex
 }
 
+func NewIni() *SysConf {
+	ini := NewSysConf("=")
+	ini.CommentCR = true
+	ini.CommentFlag = []string{"#", ";"}
+	ini.HaveSegMent = true
+	ini.SegStart = "["
+	ini.SegEnd = "]"
+	ini.SpaceStr = " "
+	ini.EscapeFlag = "\\"
+	return ini
+}
+
 func NewSysConf(EqualFlag string) *SysConf {
 	syscnf := new(SysConf)
 	syscnf.EqualFlag = EqualFlag