Replace Unix tools with bash interna

gistfile1.diff

diff --git a/statistical b/statistical
index 50f443c..17423b3 100755
--- a/statistical
+++ b/statistical
@@ -20,11 +20,11 @@ fi
 for data in $SUM; do
 
     # Getting informations from parameters
-    KEY=$(echo $data | awk -F: '{printf $1}')
-    VALUE=$(echo $data | awk -F: '{print $2}')
-    
+    KEY=${data%%:*}
+    VALUE=${data##*:}
+
     # Fishing errors from wrong usage
-    if $(echo $VALUE | grep -q -v -P '^\d{1,}$'); then
+    if [[ ! $VALUE =~ ^[[:digit:]]+$ ]]; then
         echo "ERROR: Do not use characters as value! Key:$KEY"
         exit 1
     fi
@@ -71,9 +71,8 @@ done
 # Start graphing
 for data in $SUM; do
 
-    KEY=$(echo $data | awk -F: '{printf $1}')
-    REAL_KEY=$KEY
-    VALUE=$(echo $data | awk -F: '{print $2}')
+    KEY=${data%%:*}
+    VALUE=${data##*:}
     REAL_VALUE="$VALUE"