diff --git a/src/core/functions.cpp b/src/core/functions.cpp
index 5c57451d..cd46fd84 100644
--- a/src/core/functions.cpp
+++ b/src/core/functions.cpp
@@ -323,6 +323,15 @@ HNumber function_arctan(Function* f, const Function::ArgumentList& args)
     return result;
 }
 
+HNumber function_arctan2(Function* f, const Function::ArgumentList& args)
+{
+    ENSURE_ARGUMENT_COUNT(2);
+    HNumber result = HMath::arctan2(args.at(0), args.at(1));
+    if (Settings::instance()->angleUnit == 'd')
+        result = HMath::rad2deg(result);
+    return result;
+}
+
 HNumber function_sinh(Function* f, const Function::ArgumentList& args)
 {
     ENSURE_ARGUMENT_COUNT(1);
@@ -623,6 +632,12 @@ HNumber function_idiv(Function* f, const Function::ArgumentList& args)
     return HMath::idiv(args.at(0), args.at(1));
 }
 
+HNumber function_div(Function* f, const Function::ArgumentList& args)
+{
+    ENSURE_ARGUMENT_COUNT(2);
+    return HMath::idiv(args.at(0), args.at(1));
+}
+
 HNumber function_mod(Function* f, const Function::ArgumentList& args)
 {
     ENSURE_ARGUMENT_COUNT(2);
@@ -687,6 +702,7 @@ void FunctionRepo::createFunctions()
     FUNCTION_INSERT(artanh);
     FUNCTION_INSERT(arcsin);
     FUNCTION_INSERT(arctan);
+    FUNCTION_INSERT(arctan2);
     FUNCTION_INSERT(cos);
     FUNCTION_INSERT(cosh);
     FUNCTION_INSERT(cot);
@@ -714,6 +730,7 @@ void FunctionRepo::createFunctions()
     FUNCTION_INSERT(shl);
     FUNCTION_INSERT(shr);
     FUNCTION_INSERT(idiv);
+    FUNCTION_INSERT(div);
     FUNCTION_INSERT(mod);
 }
 
@@ -767,6 +784,7 @@ void FunctionRepo::setNonTranslatableFunctionUsages()
     FUNCTION_USAGE(artanh, "x");
     FUNCTION_USAGE(arcsin, "x");
     FUNCTION_USAGE(arctan, "x");
+    FUNCTION_USAGE(arctan2, "y; x");
     FUNCTION_USAGE(average, "x<sub>1</sub>; x<sub>2</sub>; ...");
     FUNCTION_USAGE(bin, "n");
     FUNCTION_USAGE(cbrt, "x");
@@ -822,6 +840,7 @@ void FunctionRepo::setTranslatableFunctionUsages()
     FUNCTION_USAGE_TR(binommean, tr("trials; probability"));
     FUNCTION_USAGE_TR(binompmf, tr("hits; trials; probability"));
     FUNCTION_USAGE_TR(binomvar, tr("trials; probability"));
+    FUNCTION_USAGE_TR(div, tr("dividend; divisor"));
     FUNCTION_USAGE_TR(hypercdf, tr("max; total; hits; trials"));
     FUNCTION_USAGE_TR(hypermean, tr("total; hits; trials"));
     FUNCTION_USAGE_TR(hyperpmf, tr("count; total; hits; trials"));
@@ -850,6 +869,7 @@ void FunctionRepo::setFunctionNames()
     FUNCTION_NAME(artanh, tr("Area Hyperbolic Tangent"));
     FUNCTION_NAME(arcsin, tr("Arc Sine"));
     FUNCTION_NAME(arctan, tr("Arc Tangent"));
+    FUNCTION_NAME(arctan2, tr("Arc Tangent from Cathedus"));
     FUNCTION_NAME(average, tr("Average (Arithmetic Mean)"));
     FUNCTION_NAME(bin, tr("Binary Representation"));
     FUNCTION_NAME(binomcdf, tr("Binomial Cumulative Distribution Function"));
@@ -864,6 +884,7 @@ void FunctionRepo::setFunctionNames()
     FUNCTION_NAME(csc, tr("Cosecant"));
     FUNCTION_NAME(dec, tr("Decimal Representation"));
     FUNCTION_NAME(degrees, tr("Degrees of Arc"));
+    FUNCTION_NAME(div, tr("Integer Quotient"));
     FUNCTION_NAME(erf, tr("Error Function"));
     FUNCTION_NAME(erfc, tr("Complementary Error Function"));
     FUNCTION_NAME(exp, tr("Exponential"));
diff --git a/src/math/floathmath.c b/src/math/floathmath.c
index 42251ac4..502664cd 100644
--- a/src/math/floathmath.c
+++ b/src/math/floathmath.c
@@ -318,6 +318,21 @@ float_arctan(
   return 1;
 }
 
+char
+float_arctan2(
+  floatnum x,
+  floatnum y,
+  int digits)
+{
+  if (!chckmathparam(x, digits))
+    return 0;
+  if (!chckmathparam(y, digits))
+    return 0;
+  float_div(x, x, y, digits);
+  _arctan(x, digits);
+  return 1;
+}
+
 char
 float_arcsin(
   floatnum x,
diff --git a/src/math/floathmath.h b/src/math/floathmath.h
index 76fa428f..1ad41000 100644
--- a/src/math/floathmath.h
+++ b/src/math/floathmath.h
@@ -176,6 +176,12 @@ char float_power10(floatnum x, int digits);
            InvalidPrecision (digits > MATHPRECISION) */
 char float_arctan(floatnum x, int digits);
 
+/* evaluates arctan of arguments, resulting in a full circle
+   -pi<x<= pi range.
+   Errors: NaNOperand
+           InvalidPrecision (digits > MATHPRECISION) */
+char float_arctan2(floatnum y, floatnum x, int digits);
+
 /* evaluates arcsin x for -1 <= x <= 1, yielding a result
    -pi/2 <= result <= pi/2.
    In case of an error, x is set to NaN and 0 is returned.
diff --git a/src/math/floatnum.h b/src/math/floatnum.h
index 24ef12ee..f0d354aa 100644
--- a/src/math/floatnum.h
+++ b/src/math/floatnum.h
@@ -118,7 +118,7 @@ void float_create(floatnum f);
    any subsequent arithmetic operation on this variable will fail.
    However, a variable such finalized can still be re-used without prior
    initialization, by making it the destination of an operation.
-   If you wish to deliberately "empty" a variable, without detroying it,
+   If you wish to deliberately "empty" a variable, without destroying it,
    call this function.
    An alias "float_free" to this function is defined that you
    may use anywhere as a replacement for float_setnan.
diff --git a/src/math/hmath.cpp b/src/math/hmath.cpp
index e1dfcc08..a7752c4b 100644
--- a/src/math/hmath.cpp
+++ b/src/math/hmath.cpp
@@ -1232,6 +1232,32 @@ HNumber HMath::arctan( const HNumber & x )
   return result;
 };
 
+/**
+ * Returns the arc tangent calculated from the two cathedus.
+ * It's calculated from (opposite leg / adjacent leg) and
+ * results in a full circle range (-Pi;Pi) depending on
+ * the sign of the respective legs.
+ * Both legs can not be 0 the same time.
+ */
+HNumber HMath::arctan2( const HNumber & x, const HNumber & y )
+{
+/* x: opposite leg;  y: adjacent leg */
+  Error error = checkNaNParam(*x.d, y.d);
+  if (error != Success)
+    return HMath::nan(error);
+
+  if (x.isZero() && y.isZero()) return HMath::nan();
+  if (x.isPositive() && y.isZero()) return (HMath::pi()/2.0);
+  if (x.isNegative() && y.isZero()) return (0.0-(HMath::pi()/2.0));
+
+  HNumber offset = HNumber(0.0);
+  /* 2. Quadrant */
+  if (x.isPositive() && y.isNegative()) offset+=HMath::pi();
+  /* 3. Quadrant */
+  if (x.isNegative() && y.isNegative()) offset-=HMath::pi();
+  return (arctan(x/y)+offset);
+}
+
 /**
  * Returns the arc sine of x.
  */
diff --git a/src/math/hmath.h b/src/math/hmath.h
index 2c33cf23..24365ec8 100644
--- a/src/math/hmath.h
+++ b/src/math/hmath.h
@@ -144,6 +144,7 @@ class HMath
     static HNumber arcsin( const HNumber & x );
     static HNumber arccos( const HNumber & x );
     static HNumber arctan( const HNumber & x );
+    static HNumber arctan2( const HNumber & x, const HNumber & y );
     // HIGHER MATH FUNCTIONS
     static HNumber factorial( const HNumber & x, const HNumber & base = HNumber(1) );
     static HNumber gamma( const HNumber & x);
@@ -173,4 +174,4 @@ class HMath
 
 std::ostream & operator<<( std::ostream &, const HNumber & );
 
-#endif
\ No newline at end of file
+#endif