diff --git a/app/src/main/java/org/solovyev/android/calculator/ActivityLauncher.java b/app/src/main/java/org/solovyev/android/calculator/ActivityLauncher.java
index e66864be..1ac41f5f 100644
--- a/app/src/main/java/org/solovyev/android/calculator/ActivityLauncher.java
+++ b/app/src/main/java/org/solovyev/android/calculator/ActivityLauncher.java
@@ -186,7 +186,7 @@ public final class ActivityLauncher {
 
         try {
             final CustomFunction f = new CustomFunction.Builder().setName("").setParameterNames(parameters).setContent(content).create();
-            final ExpressionFunction ef = new ExpressionFunction(f, false);
+            final ExpressionFunction ef = new ExpressionFunction(f);
             plotter.get().add(ef);
             showPlotter();
         } catch (RuntimeException e) {
diff --git a/app/src/main/java/org/solovyev/android/calculator/plot/ExpressionFunction.java b/app/src/main/java/org/solovyev/android/calculator/plot/ExpressionFunction.java
index 15b693e7..50cf585c 100644
--- a/app/src/main/java/org/solovyev/android/calculator/plot/ExpressionFunction.java
+++ b/app/src/main/java/org/solovyev/android/calculator/plot/ExpressionFunction.java
@@ -1,6 +1,7 @@
 package org.solovyev.android.calculator.plot;
 
 import android.text.TextUtils;
+import jscl.math.Expression;
 import jscl.math.Generic;
 import jscl.math.JsclInteger;
 import jscl.math.NumericWrapper;
@@ -15,21 +16,18 @@ import javax.annotation.Nonnull;
 public class ExpressionFunction extends Function {
     @Nonnull
     public final jscl.math.function.Function function;
-    public final boolean imaginary;
     public final int arity;
     private final Generic[] parameters;
 
-    public ExpressionFunction(@Nonnull jscl.math.function.Function function,
-                              boolean imaginary) {
-        super(makeFunctionName(function, imaginary));
+    public ExpressionFunction(@Nonnull jscl.math.function.Function function) {
+        super(makeFunctionName(function));
         this.function = function;
-        this.imaginary = imaginary;
         this.arity = function.getMaxParameters();
         this.parameters = new Generic[this.arity];
     }
 
     @Nonnull
-    private static String makeFunctionName(@Nonnull jscl.math.function.Function function, boolean imaginary) {
+    private static String makeFunctionName(@Nonnull jscl.math.function.Function function) {
         String name = function.getName();
         if (TextUtils.isEmpty(name)) {
             if (function instanceof CustomFunction) {
@@ -41,7 +39,7 @@ public class ExpressionFunction extends Function {
                 name = name.substring(0, 10) + "…";
             }
         }
-        return imaginary ? "Im(" + name + ")" : name;
+        return name;
     }
 
     @Override
@@ -61,7 +59,7 @@ public class ExpressionFunction extends Function {
     @Override
     public float evaluate(float x) {
         try {
-            parameters[0] = new NumericWrapper(Real.valueOf(x));
+            parameters[0] = Expression.valueOf((double) x);
             function.setParameters(parameters);
             return unwrap(function.numeric());
         } catch (RuntimeException e) {
@@ -72,8 +70,8 @@ public class ExpressionFunction extends Function {
     @Override
     public float evaluate(float x, float y) {
         try {
-            parameters[0] = new NumericWrapper(Real.valueOf(x));
-            parameters[1] = new NumericWrapper(Real.valueOf(y));
+            parameters[0] = Expression.valueOf((double) x);
+            parameters[1] = Expression.valueOf((double) y);
             function.setParameters(parameters);
             return unwrap(function.numeric());
         } catch (RuntimeException e) {
@@ -96,7 +94,13 @@ public class ExpressionFunction extends Function {
             return (float) content.doubleValue();
         }
         if (content instanceof Complex) {
-            return (float) (imaginary ? ((Complex) content).imaginaryPart() : ((Complex) content).realPart());
+            final Complex complex = (Complex) content;
+            final double imag = complex.imaginaryPart();
+            final double real = complex.realPart();
+            if (real == 0f && imag != 0f) {
+                return Float.NaN;
+            }
+            return (float) real;
         }
         return Float.NaN;
     }
diff --git a/app/src/main/java/org/solovyev/android/calculator/plot/PlotEditFunctionFragment.java b/app/src/main/java/org/solovyev/android/calculator/plot/PlotEditFunctionFragment.java
index c1b522cd..0a12357e 100644
--- a/app/src/main/java/org/solovyev/android/calculator/plot/PlotEditFunctionFragment.java
+++ b/app/src/main/java/org/solovyev/android/calculator/plot/PlotEditFunctionFragment.java
@@ -150,13 +150,15 @@ public class PlotEditFunctionFragment extends BaseFunctionFragment
     protected MeshSpec applyMeshSpec() {
         final Color color = Color.create(colorPicker.getColor());
         final int width = MeshSpec.MIN_WIDTH + lineWidthSeekBar.getProgress();
-        return MeshSpec.create(color, width);
+        final MeshSpec meshSpec = MeshSpec.create(color, width);
+        meshSpec.pointsCount = 100;
+        return meshSpec;
     }
 
     protected boolean applyData(@Nonnull CppFunction function) {
         try {
             final ExpressionFunction expressionFunction =
-                new ExpressionFunction(function.toJsclBuilder().create(), false);
+                new ExpressionFunction(function.toJsclBuilder().create());
             final PlotFunction plotFunction = PlotFunction.create(expressionFunction,
                 applyMeshSpec());
             final int id = function.getId();
diff --git a/app/src/main/java/org/solovyev/android/calculator/preferences/PreferencesActivity.java b/app/src/main/java/org/solovyev/android/calculator/preferences/PreferencesActivity.java
index 78f85c4b..aaff957b 100644
--- a/app/src/main/java/org/solovyev/android/calculator/preferences/PreferencesActivity.java
+++ b/app/src/main/java/org/solovyev/android/calculator/preferences/PreferencesActivity.java
@@ -39,7 +39,6 @@ public class PreferencesActivity extends BaseActivity implements SharedPreferenc
         preferenceDefs.append(R.xml.preferences, new PrefDef("screen-main", R.string.cpp_settings));
         preferenceDefs.append(R.xml.preferences_calculations, new PrefDef("screen-calculations", R.string.c_prefs_calculations_category));
         preferenceDefs.append(R.xml.preferences_appearance, new PrefDef("screen-appearance", R.string.c_prefs_appearance_category));
-        preferenceDefs.append(R.xml.preferences_plot, new PrefDef("screen-plot", R.string.prefs_graph_screen_title));
         preferenceDefs.append(R.xml.preferences_other, new PrefDef("screen-other", R.string.c_prefs_other_category));
         preferenceDefs.append(R.xml.preferences_onscreen, new PrefDef("screen-onscreen", R.string.prefs_onscreen_title));
         preferenceDefs.append(R.xml.preferences_widget, new PrefDef("screen-widget", R.string.prefs_widget_title));
@@ -66,15 +65,6 @@ public class PreferencesActivity extends BaseActivity implements SharedPreferenc
         return preferenceDefs;
     }
 
-    public static void showPlotPreferences(@Nonnull Context context) {
-        start(context, R.xml.preferences_plot, R.string.prefs_graph_screen_title);
-    }
-
-    private static void start(@Nonnull Context context, @XmlRes int preference, @StringRes int title) {
-        final Intent intent = makeIntent(context, preference, title);
-        context.startActivity(intent);
-    }
-
     @Nonnull
     public static Intent makeIntent(@Nonnull Context context, @XmlRes int preference, @StringRes int title) {
         final Intent intent = new Intent(context, getClass(context));
diff --git a/app/src/main/res/xml/preferences.xml b/app/src/main/res/xml/preferences.xml
index 1a0365e3..0ffdadcc 100644
--- a/app/src/main/res/xml/preferences.xml
+++ b/app/src/main/res/xml/preferences.xml
@@ -41,9 +41,6 @@
     <Preference
         a:key="screen-appearance"
         a:title="@string/c_prefs_appearance_category" />
-    <Preference
-        a:key="screen-plot"
-        a:title="@string/prefs_graph_screen_title" />
     <Preference
         a:key="screen-other"
         a:title="@string/c_prefs_other_category" />
diff --git a/app/src/main/res/xml/preferences_plot.xml b/app/src/main/res/xml/preferences_plot.xml
deleted file mode 100644
index 1509387e..00000000
--- a/app/src/main/res/xml/preferences_plot.xml
+++ /dev/null
@@ -1,32 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-
-<!--
-  ~ Copyright 2013 serso aka se.solovyev
-  ~
-  ~ Licensed under the Apache License, Version 2.0 (the "License");
-  ~ you may not use this file except in compliance with the License.
-  ~ You may obtain a copy of the License at
-  ~
-  ~    http://www.apache.org/licenses/LICENSE-2.0
-  ~
-  ~ Unless required by applicable law or agreed to in writing, software
-  ~ distributed under the License is distributed on an "AS IS" BASIS,
-  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-  ~ See the License for the specific language governing permissions and
-  ~ limitations under the License.
-  ~
-  ~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-  ~ Contact details
-  ~
-  ~ Email: se.solovyev@gmail.com
-  ~ Site:  http://se.solovyev.org
-  -->
-
-<PreferenceScreen xmlns:a="http://schemas.android.com/apk/res/android">
-
-    <android.preference.CheckBoxPreference
-        a:key="graph_plot_imag"
-        a:summary="@string/cpp_prefs_graph_plot_imag_summary"
-        a:title="@string/cpp_prefs_graph_plot_imag_title" />
-
-</PreferenceScreen>
\ No newline at end of file