Rename to src

src/tools.py

@@ -0,0 +1,22 @@
+# sign function
+def sgn(x):
+    if x>=0:
+        return 1
+    return -1
+
+# check whether a number is an integer (with tolerance)
+def isint_nonzero(x):
+    if abs(x)<1e-11:
+        return False
+    return abs(round(x)-x)<1e-11
+
+# check that a number is in an interval
+def in_interval(x,a,b):
+    return x>=a and x<=b
+
+# remove x from list a
+def remove_fromlist(a,x):
+    if x in a:
+        a[a.index(x)]=a[len(a)-1]
+        a=a[:len(a)-1]
+    return a