diff --git a/src/main/java/org/apache/commons/math4/analysis/interpolation/BicubicInterpolatingFunction.java b/src/main/java/org/apache/commons/math4/analysis/interpolation/BicubicInterpolatingFunction.java
index aa2350274a..bbda65d47e 100644
--- a/src/main/java/org/apache/commons/math4/analysis/interpolation/BicubicInterpolatingFunction.java
+++ b/src/main/java/org/apache/commons/math4/analysis/interpolation/BicubicInterpolatingFunction.java
@@ -175,14 +175,10 @@ public double value(double x, double y)
      * @return {@code true} if (x, y) is a valid point.
      */
     public boolean isValidPoint(double x, double y) {
-        if (x < xval[0] ||
-            x > xval[xval.length - 1] ||
-            y < yval[0] ||
-            y > yval[yval.length - 1]) {
-            return false;
-        } else {
-            return true;
-        }
+        return !(x < xval[0]) &&
+                !(x > xval[xval.length - 1]) &&
+                !(y < yval[0]) &&
+                !(y > yval[yval.length - 1]);
     }
 
     /**
diff --git a/src/main/java/org/apache/commons/math4/analysis/interpolation/BicubicInterpolator.java b/src/main/java/org/apache/commons/math4/analysis/interpolation/BicubicInterpolator.java
index 62d16029bf..792b291872 100644
--- a/src/main/java/org/apache/commons/math4/analysis/interpolation/BicubicInterpolator.java
+++ b/src/main/java/org/apache/commons/math4/analysis/interpolation/BicubicInterpolator.java
@@ -100,14 +100,10 @@ public BicubicInterpolatingFunction interpolate(final double[] xval,
             /** {@inheritDoc} */
             @Override
             public boolean isValidPoint(double x, double y) {
-                if (x < xval[1] ||
-                    x > xval[xval.length - 2] ||
-                    y < yval[1] ||
-                    y > yval[yval.length - 2]) {
-                    return false;
-                } else {
-                    return true;
-                }
+                return !(x < xval[1]) &&
+                        !(x > xval[xval.length - 2]) &&
+                        !(y < yval[1]) &&
+                        !(y > yval[yval.length - 2]);
             }
         };
     }
diff --git a/src/main/java/org/apache/commons/math4/analysis/interpolation/PiecewiseBicubicSplineInterpolatingFunction.java b/src/main/java/org/apache/commons/math4/analysis/interpolation/PiecewiseBicubicSplineInterpolatingFunction.java
index f547a1f3b3..2e165d70e8 100644
--- a/src/main/java/org/apache/commons/math4/analysis/interpolation/PiecewiseBicubicSplineInterpolatingFunction.java
+++ b/src/main/java/org/apache/commons/math4/analysis/interpolation/PiecewiseBicubicSplineInterpolatingFunction.java
@@ -157,14 +157,10 @@ public double value(double x,
      */
     public boolean isValidPoint(double x,
                                 double y) {
-        if (x < xval[0] ||
-            x > xval[xval.length - 1] ||
-            y < yval[0] ||
-            y > yval[yval.length - 1]) {
-            return false;
-        } else {
-            return true;
-        }
+        return !(x < xval[0]) &&
+                !(x > xval[xval.length - 1]) &&
+                !(y < yval[0]) &&
+                !(y > yval[yval.length - 1]);
     }
 
     /**
diff --git a/src/main/java/org/apache/commons/math4/analysis/interpolation/TricubicInterpolatingFunction.java b/src/main/java/org/apache/commons/math4/analysis/interpolation/TricubicInterpolatingFunction.java
index ca1698bedd..587195b633 100644
--- a/src/main/java/org/apache/commons/math4/analysis/interpolation/TricubicInterpolatingFunction.java
+++ b/src/main/java/org/apache/commons/math4/analysis/interpolation/TricubicInterpolatingFunction.java
@@ -341,16 +341,12 @@ public double value(double x, double y, double z)
      * @return {@code true} if (x, y, z) is a valid point.
      */
     public boolean isValidPoint(double x, double y, double z) {
-        if (x < xval[0] ||
-            x > xval[xval.length - 1] ||
-            y < yval[0] ||
-            y > yval[yval.length - 1] ||
-            z < zval[0] ||
-            z > zval[zval.length - 1]) {
-            return false;
-        } else {
-            return true;
-        }
+        return !(x < xval[0]) &&
+                !(x > xval[xval.length - 1]) &&
+                !(y < yval[0]) &&
+                !(y > yval[yval.length - 1]) &&
+                !(z < zval[0]) &&
+                !(z > zval[zval.length - 1]);
     }
 
     /**
diff --git a/src/main/java/org/apache/commons/math4/analysis/interpolation/TricubicInterpolator.java b/src/main/java/org/apache/commons/math4/analysis/interpolation/TricubicInterpolator.java
index bdc7f201b0..60874cfdbb 100644
--- a/src/main/java/org/apache/commons/math4/analysis/interpolation/TricubicInterpolator.java
+++ b/src/main/java/org/apache/commons/math4/analysis/interpolation/TricubicInterpolator.java
@@ -128,16 +128,12 @@ public TricubicInterpolatingFunction interpolate(final double[] xval,
             /** {@inheritDoc} */
             @Override
             public boolean isValidPoint(double x, double y, double z) {
-                if (x < xval[1] ||
-                    x > xval[xval.length - 2] ||
-                    y < yval[1] ||
-                    y > yval[yval.length - 2] ||
-                    z < zval[1] ||
-                    z > zval[zval.length - 2]) {
-                    return false;
-                } else {
-                    return true;
-                }
+                return !(x < xval[1]) &&
+                        !(x > xval[xval.length - 2]) &&
+                        !(y < yval[1]) &&
+                        !(y > yval[yval.length - 2]) &&
+                        !(z < zval[1]) &&
+                        !(z > zval[zval.length - 2]);
             }
         };
     }
diff --git a/src/main/java/org/apache/commons/math4/analysis/polynomials/PolynomialFunction.java b/src/main/java/org/apache/commons/math4/analysis/polynomials/PolynomialFunction.java
index 9333c1eb3f..56330e3b71 100644
--- a/src/main/java/org/apache/commons/math4/analysis/polynomials/PolynomialFunction.java
+++ b/src/main/java/org/apache/commons/math4/analysis/polynomials/PolynomialFunction.java
@@ -372,10 +372,7 @@ public boolean equals(Object obj) {
             return false;
         }
         PolynomialFunction other = (PolynomialFunction) obj;
-        if (!Arrays.equals(coefficients, other.coefficients)) {
-            return false;
-        }
-        return true;
+        return Arrays.equals(coefficients, other.coefficients);
     }
 
     /**
diff --git a/src/main/java/org/apache/commons/math4/analysis/polynomials/PolynomialSplineFunction.java b/src/main/java/org/apache/commons/math4/analysis/polynomials/PolynomialSplineFunction.java
index d7263c2fdc..847693af00 100644
--- a/src/main/java/org/apache/commons/math4/analysis/polynomials/PolynomialSplineFunction.java
+++ b/src/main/java/org/apache/commons/math4/analysis/polynomials/PolynomialSplineFunction.java
@@ -227,11 +227,7 @@ public double[] getKnots() {
      * @return {@code true} if {@code x} is a valid point.
      */
     public boolean isValidPoint(double x) {
-        if (x < knots[0] ||
-            x > knots[n]) {
-            return false;
-        } else {
-            return true;
-        }
+        return !(x < knots[0]) &&
+                !(x > knots[n]);
     }
 }
diff --git a/src/main/java/org/apache/commons/math4/dfp/Dfp.java b/src/main/java/org/apache/commons/math4/dfp/Dfp.java
index 841ec2f32b..4ec5c5845d 100644
--- a/src/main/java/org/apache/commons/math4/dfp/Dfp.java
+++ b/src/main/java/org/apache/commons/math4/dfp/Dfp.java
@@ -2365,10 +2365,7 @@ public Dfp nextAfter(final Dfp x) {
         }
 
         // if this is greater than x
-        boolean up = false;
-        if (this.lessThan(x)) {
-            up = true;
-        }
+        boolean up = this.lessThan(x);
 
         if (compare(this, x) == 0) {
             return newInstance(x);
diff --git a/src/main/java/org/apache/commons/math4/dfp/DfpMath.java b/src/main/java/org/apache/commons/math4/dfp/DfpMath.java
index 734c8faf60..5c6aca209d 100644
--- a/src/main/java/org/apache/commons/math4/dfp/DfpMath.java
+++ b/src/main/java/org/apache/commons/math4/dfp/DfpMath.java
@@ -945,11 +945,7 @@ public static Dfp asin(final Dfp a) {
      */
     public static Dfp acos(Dfp a) {
         Dfp result;
-        boolean negative = false;
-
-        if (a.lessThan(a.getZero())) {
-            negative = true;
-        }
+        boolean negative = a.lessThan(a.getZero());
 
         a = Dfp.copysign(a, a.getOne());  // absolute value
 
diff --git a/src/main/java/org/apache/commons/math4/fitting/GaussianCurveFitter.java b/src/main/java/org/apache/commons/math4/fitting/GaussianCurveFitter.java
index 93d99b657e..55bea82f8e 100644
--- a/src/main/java/org/apache/commons/math4/fitting/GaussianCurveFitter.java
+++ b/src/main/java/org/apache/commons/math4/fitting/GaussianCurveFitter.java
@@ -273,10 +273,7 @@ public int compare(WeightedObservedPoint p1,
                         return comp;
                     }
                     comp = Double.compare(p1.getWeight(), p2.getWeight());
-                    if (comp != 0) {
-                        return comp;
-                    }
-                    return 0;
+                    return comp;
                 }
             };
 
diff --git a/src/main/java/org/apache/commons/math4/ode/events/EventState.java b/src/main/java/org/apache/commons/math4/ode/events/EventState.java
index 76ef13d755..cf5310ae43 100644
--- a/src/main/java/org/apache/commons/math4/ode/events/EventState.java
+++ b/src/main/java/org/apache/commons/math4/ode/events/EventState.java
@@ -365,7 +365,7 @@ public void stepAccepted(final double t, final double[] y) {
             // force the sign to its value "just after the event"
             previousEventTime = t;
             g0Positive        = increasing;
-            nextAction        = handler.eventOccurred(t, y, !(increasing ^ forward));
+            nextAction        = handler.eventOccurred(t, y, increasing == forward);
         } else {
             g0Positive = g0 >= 0;
             nextAction = EventHandler.Action.CONTINUE;
diff --git a/src/main/java/org/apache/commons/math4/ode/events/FieldEventState.java b/src/main/java/org/apache/commons/math4/ode/events/FieldEventState.java
index cfbbd4343e..cb0763e7b9 100644
--- a/src/main/java/org/apache/commons/math4/ode/events/FieldEventState.java
+++ b/src/main/java/org/apache/commons/math4/ode/events/FieldEventState.java
@@ -301,7 +301,7 @@ public void stepAccepted(final FieldODEStateAndDerivative<T> state) {
             // force the sign to its value "just after the event"
             previousEventTime = state.getTime();
             g0Positive        = increasing;
-            nextAction        = handler.eventOccurred(state, !(increasing ^ forward));
+            nextAction        = handler.eventOccurred(state, increasing == forward);
         } else {
             g0Positive = g0.getReal() >= 0;
             nextAction = Action.CONTINUE;
diff --git a/src/main/java/org/apache/commons/math4/optim/linear/SolutionCallback.java b/src/main/java/org/apache/commons/math4/optim/linear/SolutionCallback.java
index a14409d67f..66b7479316 100644
--- a/src/main/java/org/apache/commons/math4/optim/linear/SolutionCallback.java
+++ b/src/main/java/org/apache/commons/math4/optim/linear/SolutionCallback.java
@@ -57,6 +57,6 @@ public PointValuePair getSolution() {
      * @return {@code true} if the solution is optimal, {@code false} otherwise
      */
     public boolean isSolutionOptimal() {
-        return tableau != null ? tableau.isOptimal() : false;
+        return tableau != null && tableau.isOptimal();
     }
 }
diff --git a/src/main/java/org/apache/commons/math4/stat/Frequency.java b/src/main/java/org/apache/commons/math4/stat/Frequency.java
index 66629cec6f..21031a1238 100644
--- a/src/main/java/org/apache/commons/math4/stat/Frequency.java
+++ b/src/main/java/org/apache/commons/math4/stat/Frequency.java
@@ -378,13 +378,10 @@ public boolean equals(Object obj) {
         }
         Frequency<?> other = (Frequency<?>) obj;
         if (freqTable == null) {
-            if (other.freqTable != null) {
-                return false;
-            }
-        } else if (!freqTable.equals(other.freqTable)) {
-            return false;
+            return other.freqTable == null;
+        } else {
+            return freqTable.equals(other.freqTable);
         }
-        return true;
     }
 
 }
diff --git a/src/main/java/org/apache/commons/math4/stat/descriptive/moment/VectorialCovariance.java b/src/main/java/org/apache/commons/math4/stat/descriptive/moment/VectorialCovariance.java
index cf27522645..7bb4b9eddf 100644
--- a/src/main/java/org/apache/commons/math4/stat/descriptive/moment/VectorialCovariance.java
+++ b/src/main/java/org/apache/commons/math4/stat/descriptive/moment/VectorialCovariance.java
@@ -148,10 +148,7 @@ public boolean equals(Object obj) {
         if (!Arrays.equals(productsSums, other.productsSums)) {
             return false;
         }
-        if (!Arrays.equals(sums, other.sums)) {
-            return false;
-        }
-        return true;
+        return Arrays.equals(sums, other.sums);
     }
 
 }
diff --git a/src/main/java/org/apache/commons/math4/stat/descriptive/moment/VectorialMean.java b/src/main/java/org/apache/commons/math4/stat/descriptive/moment/VectorialMean.java
index cdc5a26a2a..01af0edd61 100644
--- a/src/main/java/org/apache/commons/math4/stat/descriptive/moment/VectorialMean.java
+++ b/src/main/java/org/apache/commons/math4/stat/descriptive/moment/VectorialMean.java
@@ -96,10 +96,7 @@ public boolean equals(Object obj) {
             return false;
         }
         VectorialMean other = (VectorialMean) obj;
-        if (!Arrays.equals(means, other.means)) {
-            return false;
-        }
-        return true;
+        return Arrays.equals(means, other.means);
     }
 
 }
diff --git a/src/main/java/org/apache/commons/math4/stat/descriptive/rank/PSquarePercentile.java b/src/main/java/org/apache/commons/math4/stat/descriptive/rank/PSquarePercentile.java
index e0381edf7b..f7130a96fc 100644
--- a/src/main/java/org/apache/commons/math4/stat/descriptive/rank/PSquarePercentile.java
+++ b/src/main/java/org/apache/commons/math4/stat/descriptive/rank/PSquarePercentile.java
@@ -908,7 +908,7 @@ private static class FixedCapacityList<E> extends ArrayList<E> implements Serial
          */
         @Override
         public boolean add(final E e) {
-            return size() < capacity ? super.add(e) : false;
+            return size() < capacity && super.add(e);
         }
 
         /**
@@ -924,7 +924,7 @@ public boolean addAll(Collection<? extends E> collection) {
             boolean isCollectionLess =
                     collection != null &&
                             collection.size() + size() <= capacity;
-            return isCollectionLess ? super.addAll(collection) : false;
+            return isCollectionLess && super.addAll(collection);
         }
     }
 
diff --git a/src/main/java/org/apache/commons/math4/stat/inference/KolmogorovSmirnovTest.java b/src/main/java/org/apache/commons/math4/stat/inference/KolmogorovSmirnovTest.java
index 4a670cbc10..85e47558cf 100644
--- a/src/main/java/org/apache/commons/math4/stat/inference/KolmogorovSmirnovTest.java
+++ b/src/main/java/org/apache/commons/math4/stat/inference/KolmogorovSmirnovTest.java
@@ -1133,11 +1133,7 @@ private static boolean hasTies(double[] x, double[] y) {
            throw new InsufficientDataException();
        }
 
-       if (values.length == x.length + y.length) {
-           return false;  // There are no ties.
-       }
-
-       return true;
+       return values.length != x.length + y.length;  // There are no ties.
     }
 
     /**
diff --git a/src/main/java/org/apache/commons/math4/util/MathArrays.java b/src/main/java/org/apache/commons/math4/util/MathArrays.java
index 864dbcf4ff..f5f1c23246 100644
--- a/src/main/java/org/apache/commons/math4/util/MathArrays.java
+++ b/src/main/java/org/apache/commons/math4/util/MathArrays.java
@@ -777,7 +777,7 @@ public int compare(PairDoubleInteger o1,
      */
     public static boolean equals(float[] x, float[] y) {
         if ((x == null) || (y == null)) {
-            return !((x == null) ^ (y == null));
+            return (x == null) == (y == null);
         }
         if (x.length != y.length) {
             return false;
@@ -803,7 +803,7 @@ public static boolean equals(float[] x, float[] y) {
      */
     public static boolean equalsIncludingNaN(float[] x, float[] y) {
         if ((x == null) || (y == null)) {
-            return !((x == null) ^ (y == null));
+            return (x == null) == (y == null);
         }
         if (x.length != y.length) {
             return false;
@@ -828,7 +828,7 @@ public static boolean equalsIncludingNaN(float[] x, float[] y) {
      */
     public static boolean equals(double[] x, double[] y) {
         if ((x == null) || (y == null)) {
-            return !((x == null) ^ (y == null));
+            return (x == null) == (y == null);
         }
         if (x.length != y.length) {
             return false;
@@ -854,7 +854,7 @@ public static boolean equals(double[] x, double[] y) {
      */
     public static boolean equalsIncludingNaN(double[] x, double[] y) {
         if ((x == null) || (y == null)) {
-            return !((x == null) ^ (y == null));
+            return (x == null) == (y == null);
         }
         if (x.length != y.length) {
             return false;
@@ -1117,11 +1117,7 @@ public static boolean verifyValues(final double[] values, final int begin,
                     Integer.valueOf(begin + length), Integer.valueOf(values.length), true);
         }
 
-        if (length == 0 && !allowEmpty) {
-            return false;
-        }
-
-        return true;
+        return length != 0 || allowEmpty;
 
     }