diff --git a/check/qlibs_cpp_test.cpp b/check/qlibs_cpp_test.cpp
index 606c9a5..dbf41e3 100644
--- a/check/qlibs_cpp_test.cpp
+++ b/check/qlibs_cpp_test.cpp
@@ -299,6 +299,7 @@ void test_ltisys( void )
 void test_ffmath(void)
 {
     cout << "ffmath" << endl;
+    cout << ffmath::sqrt( 0.5f ) << endl;
     cout << ffmath::exp( 0.5f ) << endl;
     cout << ffmath::log( 0.5f ) << endl;
     cout << ffmath::sin( 0.5f ) << endl;
@@ -328,7 +329,8 @@ void test_ffmath(void)
     cout << ffmath::assoc_legendre( 2, 1, 0.5f ) << endl;
     cout << ffmath::assoc_legendre( 2, 2, 0.5f ) << endl;
 
-
+    std::cout << "beta" << std::endl;
+    std::cout << ffmath::beta(0.123f, 1.0f - 0.123f) << std::endl;
     std::cout << ffmath::beta(0.1f, 0.2f) << std::endl;
     std::cout << "comp_ellint_1" << std::endl;
     std::cout << ffmath::comp_ellint_1( 0.0f ) << std::endl;
diff --git a/check/sa_check.ewp b/check/sa_check.ewp
index 624ac46..2d92915 100644
--- a/check/sa_check.ewp
+++ b/check/sa_check.ewp
@@ -2237,6 +2237,9 @@
         <file>
             <name>$PROJ_DIR$\..\src\include\pid.hpp</name>
         </file>
+        <file>
+            <name>$PROJ_DIR$\..\src\include\qlibs_types.hpp</name>
+        </file>
         <file>
             <name>$PROJ_DIR$\..\src\include\rms.hpp</name>
         </file>
diff --git a/check/sa_check.ewt b/check/sa_check.ewt
index d681435..d844582 100644
--- a/check/sa_check.ewt
+++ b/check/sa_check.ewt
@@ -2967,6 +2967,9 @@
         <file>
             <name>$PROJ_DIR$\..\src\include\pid.hpp</name>
         </file>
+        <file>
+            <name>$PROJ_DIR$\..\src\include\qlibs_types.hpp</name>
+        </file>
         <file>
             <name>$PROJ_DIR$\..\src\include\rms.hpp</name>
         </file>
diff --git a/src/ffmath.cpp b/src/ffmath.cpp
index 1e5119c..9b5cc5c 100644
--- a/src/ffmath.cpp
+++ b/src/ffmath.cpp
@@ -12,9 +12,6 @@ struct limits {
 
 constexpr uint32_t F32_NO_SIGN_MASK = 0x7FFFFFFFU;
 constexpr uint32_t F32_SIGN_MASK = 0x80000000U;
-constexpr uint32_t F32_EXPONENT_MASK = 0x7F800000U;
-constexpr uint32_t F32_MANTISSA_MASK = 0x007FFFFFU;
-constexpr uint32_t F32_MANTISSA_NBITS = 23U;
 
 using namespace qlibs;
 
@@ -1797,7 +1794,7 @@ float ffmath::comp_ellint_1( float k )
 {
     float y;
 
-    if ( ffmath::isNan( k ) || ( absolute( k ) >= 1.0F ) ) {
+    if ( ffmath::isNan( k ) || ( absolute( k ) >= 1.0F ) ) { //no side effects
         y = ffmath::getNan();
     }
     else {
diff --git a/src/include/interp1.hpp b/src/include/interp1.hpp
index 9ef556c..b3d08a7 100644
--- a/src/include/interp1.hpp
+++ b/src/include/interp1.hpp
@@ -3,11 +3,7 @@
  * @author J. Camilo Gomez C.
  * @version 1.01
  * @note This file is part of the qLibs-cpp distribution.
- * @brief Helper class that implements a Tapped Delay Line (TDL). A TDL is a
- * delay line that provides access to its contents at arbitrary intermediate
- * delay length values.
- * This class runs in constant time O(1), so it becomes useful when you need to
- * work with long delayed lines.
+ * @brief 1D Interpolation Class
  **/
 
 #ifndef QLIBS_INTERP1
@@ -24,9 +20,9 @@ namespace qlibs {
     *  @{
     */
 
-        /**
-        * @brief An enum with all the available interpolation methods.
-        */
+    /**
+    * @brief An enum with all the available interpolation methods.
+    */
     enum interp1Method {
         INTERP1_NEXT = 0,               /*!< Return the next neighbor.*/
         INTERP1_PREVIOUS,               /*!< Return the previous neighbor.*/
@@ -170,6 +166,7 @@ namespace qlibs {
             * @brief Interpolate input point @a x to determine the value of @a y
             * at the points @a xi using the current method. If value is beyond
             * the endpoints, extrapolation is performed using the current method.
+            * @param[in] x The input point.
             * @return @c The interpolated-extrapolated @a y value.
             */
             inline real_t get( const T x ) noexcept
diff --git a/src/interp1.cpp b/src/interp1.cpp
index 84ef3ff..f069595 100644
--- a/src/interp1.cpp
+++ b/src/interp1.cpp
@@ -20,7 +20,7 @@ bool interp1::setMethod( const interp1Method m ) noexcept
         &interp1::cSpline,
     };
 
-    if ( ( m > 0 ) && ( m < INTERP1_MAX ) ) {
+    if ( ( m >= 0 ) && ( m < INTERP1_MAX ) ) {
         method = im[ m ];
         retValue = true;
     }