diff --git a/src/barchart/qbarset.cpp b/src/barchart/qbarset.cpp
index ff5f0ba..9c86014 100644
--- a/src/barchart/qbarset.cpp
+++ b/src/barchart/qbarset.cpp
@@ -555,14 +555,18 @@ QBarSetPrivate::~QBarSetPrivate()
 
 void QBarSetPrivate::append(QPointF value)
 {
-    m_values.append(value);
-    emit restructuredBars();
+    if (isValidValue(value)) {
+        m_values.append(value);
+        emit restructuredBars();
+    }
 }
 
 void QBarSetPrivate::append(QList<QPointF> values)
 {
-    for (int i = 0; i < values.count(); i++)
-        m_values.append(values.at(i));
+    for (int i = 0; i < values.count(); i++) {
+        if (isValidValue(values.at(i)))
+            m_values.append(values.at(i));
+    }
     emit restructuredBars();
 }
 
@@ -570,8 +574,10 @@ void QBarSetPrivate::append(QList<qreal> values)
 {
     int index = m_values.count();
     for (int i = 0; i < values.count(); i++) {
-        m_values.append(QPointF(index, values.at(i)));
-        index++;
+        if (isValidValue(values.at(i))) {
+            m_values.append(QPointF(index, values.at(i)));
+            index++;
+        }
     }
     emit restructuredBars();
 }
diff --git a/src/barchart/qbarset.h b/src/barchart/qbarset.h
index c2bfb5a..d2b2d99 100644
--- a/src/barchart/qbarset.h
+++ b/src/barchart/qbarset.h
@@ -25,6 +25,7 @@
 #include <QPen>
 #include <QBrush>
 #include <QFont>
+#include "charthelpers_p.h"
 
 QTCOMMERCIALCHART_BEGIN_NAMESPACE
 class QBarSetPrivate;
diff --git a/src/charthelpers_p.h b/src/charthelpers_p.h
new file mode 100644
index 0000000..63e5cfa
--- /dev/null
+++ b/src/charthelpers_p.h
@@ -0,0 +1,26 @@
+#ifndef CHARTHELPERS_P_H
+#define CHARTHELPERS_P_H
+
+#include <qnumeric.h>
+#include <QPointF>
+
+static inline bool isValidValue(qreal value)
+{
+    if (qIsNaN(value) || qIsInf(value)) {
+        qWarning("Ignored NaN, Inf, or -Inf value.");
+        return false;
+    }
+    return true;
+}
+
+static inline bool isValidValue(qreal x, qreal y)
+{
+    return (isValidValue(x) && isValidValue(y));
+}
+
+static inline bool isValidValue(const QPointF point)
+{
+    return (isValidValue(point.x()) && isValidValue(point.y()));
+}
+
+#endif // CHARTHELPERS_P_H
diff --git a/src/piechart/qpieseries.cpp b/src/piechart/qpieseries.cpp
index 3927ffb..df690a9 100644
--- a/src/piechart/qpieseries.cpp
+++ b/src/piechart/qpieseries.cpp
@@ -27,6 +27,7 @@
 #include "charttheme_p.h"
 #include "qabstractaxis.h"
 #include "pieanimation_p.h"
+#include "charthelpers_p.h"
 
 #include "qpielegendmarker.h"
 
@@ -400,6 +401,8 @@ bool QPieSeries::append(QList<QPieSlice *> slices)
             return false;
         if (s->series()) // already added to some series
             return false;
+        if (!isValidValue(s->value()))
+            return false;
     }
 
     foreach (QPieSlice *s, slices) {
@@ -436,12 +439,17 @@ QPieSeries &QPieSeries::operator << (QPieSlice *slice)
 /*!
     Appends a single slice to the series with give \a value and \a label.
     Slice ownership is passed to the series.
+    Returns NULL if value is NaN, Inf or -Inf and no slice is added to the series.
 */
 QPieSlice *QPieSeries::append(QString label, qreal value)
 {
-    QPieSlice *slice = new QPieSlice(label, value);
-    append(slice);
-    return slice;
+    if (isValidValue(value)) {
+        QPieSlice *slice = new QPieSlice(label, value);
+        append(slice);
+        return slice;
+    } else {
+        return 0;
+    }
 }
 
 /*!
@@ -463,6 +471,9 @@ bool QPieSeries::insert(int index, QPieSlice *slice)
     if (slice->series()) // already added to some series
         return false;
 
+    if (!isValidValue(slice->value()))
+        return false;
+
     slice->setParent(this);
     QPieSlicePrivate::fromSlice(slice)->m_series = this;
     d->m_slices.insert(index, slice);
diff --git a/src/src.pro b/src/src.pro
index 90a3be9..48a83a3 100644
--- a/src/src.pro
+++ b/src/src.pro
@@ -54,7 +54,8 @@ PRIVATE_HEADERS += \
     $$PWD/scroller_p.h \
     $$PWD/qabstractseries_p.h \
     $$PWD/chartlayout_p.h \
-    $$PWD/charttitle_p.h
+    $$PWD/charttitle_p.h \
+    $$PWD/charthelpers_p.h
 PUBLIC_HEADERS += \
     $$PWD/qchart.h \
     $$PWD/qchartglobal.h \
diff --git a/src/xychart/qxyseries.cpp b/src/xychart/qxyseries.cpp
index f3e8960..05d2abc 100644
--- a/src/xychart/qxyseries.cpp
+++ b/src/xychart/qxyseries.cpp
@@ -24,6 +24,7 @@
 #include "qvalueaxis.h"
 #include "xychart_p.h"
 #include "qxylegendmarker.h"
+#include "charthelpers_p.h"
 
 QTCOMMERCIALCHART_BEGIN_NAMESPACE
 
@@ -243,8 +244,11 @@ void QXYSeries::append(qreal x, qreal y)
 void QXYSeries::append(const QPointF &point)
 {
     Q_D(QXYSeries);
-    d->m_points << point;
-    emit pointAdded(d->m_points.count() - 1);
+
+    if (isValidValue(point)) {
+        d->m_points << point;
+        emit pointAdded(d->m_points.count() - 1);
+    }
 }
 
 /*!
@@ -276,8 +280,10 @@ void QXYSeries::replace(const QPointF &oldPoint, const QPointF &newPoint)
     int index = d->m_points.indexOf(oldPoint);
     if (index == -1)
         return;
-    d->m_points[index] = newPoint;
-    emit pointReplaced(index);
+    if (isValidValue(newPoint)) {
+        d->m_points[index] = newPoint;
+        emit pointReplaced(index);
+    }
 }
 
 /*!
@@ -322,8 +328,10 @@ void QXYSeries::remove(const QPointF &point)
 void QXYSeries::insert(int index, const QPointF &point)
 {
     Q_D(QXYSeries);
-    d->m_points.insert(index, point);
-    emit pointAdded(index);
+    if (isValidValue(point)) {
+        d->m_points.insert(index, point);
+        emit pointAdded(index);
+    }
 }
 
 /*!