Additions to GREL:

* modulo operator, %
* cos, sin and tan functions
* acos, asin, atan and atan2 functions
* cosh, sinh and tanh functions
* fact and combin functions
* degrees and radians functions
* odd and even functions

git-svn-id: http://google-refine.googlecode.com/svn/trunk@1908 7d457c2a-affb-35e4-300a-418c747d4874

main/src/com/google/refine/expr/functions/math/ACos.java

@@ -0,0 +1,63 @@
+/*
+
+Copyright 2010, Google Inc.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+    * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+*/
+
+package com.google.refine.expr.functions.math;
+
+import java.util.Properties;
+
+import org.json.JSONException;
+import org.json.JSONWriter;
+
+import com.google.refine.expr.EvalError;
+import com.google.refine.grel.ControlFunctionRegistry;
+import com.google.refine.grel.Function;
+
+public class ACos implements Function {
+
+    public Object call(Properties bindings, Object[] args) {
+        if (args.length == 1 && args[0] != null && args[0] instanceof Number) {
+            return Math.acos(((Number) args[0]).doubleValue());
+        }
+        return new EvalError(ControlFunctionRegistry.getFunctionName(this) + " expects a number");
+    }
+
+    public void write(JSONWriter writer, Properties options)
+        throws JSONException {
+
+        writer.object();
+        writer.key("description"); writer.value("Returns the arc cosine of an angle, in the range 0 through PI");
+        writer.key("params"); writer.value("number d");
+        writer.key("returns"); writer.value("number");
+        writer.endObject();
+    }
+}

main/src/com/google/refine/expr/functions/math/ASin.java

@@ -0,0 +1,63 @@
+/*
+
+Copyright 2010, Google Inc.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+    * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+*/
+
+package com.google.refine.expr.functions.math;
+
+import java.util.Properties;
+
+import org.json.JSONException;
+import org.json.JSONWriter;
+
+import com.google.refine.expr.EvalError;
+import com.google.refine.grel.ControlFunctionRegistry;
+import com.google.refine.grel.Function;
+
+public class ASin implements Function {
+
+    public Object call(Properties bindings, Object[] args) {
+        if (args.length == 1 && args[0] != null && args[0] instanceof Number) {
+            return Math.asin(((Number) args[0]).doubleValue());
+        }
+        return new EvalError(ControlFunctionRegistry.getFunctionName(this) + " expects a number");
+    }
+
+    public void write(JSONWriter writer, Properties options)
+        throws JSONException {
+
+        writer.object();
+        writer.key("description"); writer.value("Returns the arc sine of an angle in the range of -PI/2 through PI/2");
+        writer.key("params"); writer.value("number d");
+        writer.key("returns"); writer.value("number");
+        writer.endObject();
+    }
+}

main/src/com/google/refine/expr/functions/math/ATan.java

@@ -0,0 +1,63 @@
+/*
+
+Copyright 2010, Google Inc.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+    * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+*/
+
+package com.google.refine.expr.functions.math;
+
+import java.util.Properties;
+
+import org.json.JSONException;
+import org.json.JSONWriter;
+
+import com.google.refine.expr.EvalError;
+import com.google.refine.grel.ControlFunctionRegistry;
+import com.google.refine.grel.Function;
+
+public class ATan implements Function {
+
+    public Object call(Properties bindings, Object[] args) {
+        if (args.length == 1 && args[0] != null && args[0] instanceof Number) {
+            return Math.atan(((Number) args[0]).doubleValue());
+        }
+        return new EvalError(ControlFunctionRegistry.getFunctionName(this) + " expects a number");
+    }
+
+    public void write(JSONWriter writer, Properties options)
+        throws JSONException {
+
+        writer.object();
+        writer.key("description"); writer.value("Returns the arc tangent of an angle in the range of -PI/2 through PI/2");
+        writer.key("params"); writer.value("number d");
+        writer.key("returns"); writer.value("number");
+        writer.endObject();
+    }
+}

main/src/com/google/refine/expr/functions/math/ATan2.java

@@ -0,0 +1,64 @@
+/*
+
+Copyright 2010, Google Inc.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+    * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+*/
+
+package com.google.refine.expr.functions.math;
+
+import java.util.Properties;
+
+import org.json.JSONException;
+import org.json.JSONWriter;
+
+import com.google.refine.expr.EvalError;
+import com.google.refine.grel.ControlFunctionRegistry;
+import com.google.refine.grel.Function;
+
+public class ATan2 implements Function {
+
+    public Object call(Properties bindings, Object[] args) {
+        if (args.length == 2 && args[0] != null && args[0] instanceof Number
+                && args[1] != null && args[1] instanceof Number) {
+            return Math.atan2(((Number) args[0]).doubleValue(),((Number) args[1]).doubleValue());
+        }
+        return new EvalError(ControlFunctionRegistry.getFunctionName(this) + " expects a number");
+    }
+
+    public void write(JSONWriter writer, Properties options)
+        throws JSONException {
+
+        writer.object();
+        writer.key("description"); writer.value("Converts rectangular coordinates (x, y) to polar (r, theta)");
+        writer.key("params"); writer.value("number x, number y");
+        writer.key("returns"); writer.value("number theta");
+        writer.endObject();
+    }
+}

main/src/com/google/refine/expr/functions/math/Combin.java

@@ -0,0 +1,78 @@
+/*
+
+Copyright 2010, Google Inc.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+    * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+*/
+
+package com.google.refine.expr.functions.math;
+
+import java.util.Properties;
+
+import org.json.JSONException;
+import org.json.JSONWriter;
+
+import com.google.refine.expr.EvalError;
+import com.google.refine.grel.ControlFunctionRegistry;
+import com.google.refine.grel.Function;
+
+public class Combin implements Function {
+
+    public Object call(Properties bindings, Object[] args) {
+        if(args.length != 2)
+            return new EvalError(ControlFunctionRegistry.getFunctionName(this) + " expects two numbers");
+        if(args[0] == null || !(args[0] instanceof Number))
+            return new EvalError(ControlFunctionRegistry.getFunctionName(this) + " expects the first argument to be a number");
+        if(args[1] == null || !(args[1] instanceof Number))
+            return new EvalError(ControlFunctionRegistry.getFunctionName(this) + " expects the second argument to be a number");
+
+        return Combin.Combination(((Number) args[0]).intValue(), ((Number) args[1]).intValue());
+    }
+
+    public static int Combination(int n, int k){
+        if (k > n)
+            throw new IllegalArgumentException ("the number of elements, n, should be larger than the number of combinations, k");
+        if (n < 1)
+            throw new IllegalArgumentException ("the number of elements, n, cannot be less than 1");
+        int nFact = Fact.factorial(n);
+        int rFact = Fact.factorial(k);
+        int nminusrFact = Fact.factorial(n - k);
+        return nFact / (rFact * nminusrFact);
+    }
+
+    public void write(JSONWriter writer, Properties options)
+        throws JSONException {
+
+        writer.object();
+        writer.key("description"); writer.value("Returns the number of combinations for n elements as divided into k");
+        writer.key("params"); writer.value("number d");
+        writer.key("returns"); writer.value("number");
+        writer.endObject();
+    }
+}

main/src/com/google/refine/expr/functions/math/Cos.java

@@ -0,0 +1,63 @@
+/*
+
+Copyright 2010, Google Inc.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+    * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+*/
+
+package com.google.refine.expr.functions.math;
+
+import java.util.Properties;
+
+import org.json.JSONException;
+import org.json.JSONWriter;
+
+import com.google.refine.expr.EvalError;
+import com.google.refine.grel.ControlFunctionRegistry;
+import com.google.refine.grel.Function;
+
+public class Cos implements Function {
+
+    public Object call(Properties bindings, Object[] args) {
+        if (args.length == 1 && args[0] != null && args[0] instanceof Number) {
+            return Math.cos(((Number) args[0]).doubleValue());
+        }
+        return new EvalError(ControlFunctionRegistry.getFunctionName(this) + " expects a number");
+    }
+
+    public void write(JSONWriter writer, Properties options)
+        throws JSONException {
+
+        writer.object();
+        writer.key("description"); writer.value("Returns the trigonometric cosine of an angle");
+        writer.key("params"); writer.value("number d");
+        writer.key("returns"); writer.value("number");
+        writer.endObject();
+    }
+}

main/src/com/google/refine/expr/functions/math/Cosh.java

@@ -0,0 +1,63 @@
+/*
+
+Copyright 2010, Google Inc.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+    * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+*/
+
+package com.google.refine.expr.functions.math;
+
+import java.util.Properties;
+
+import org.json.JSONException;
+import org.json.JSONWriter;
+
+import com.google.refine.expr.EvalError;
+import com.google.refine.grel.ControlFunctionRegistry;
+import com.google.refine.grel.Function;
+
+public class Cosh implements Function {
+
+    public Object call(Properties bindings, Object[] args) {
+        if (args.length == 1 && args[0] != null && args[0] instanceof Number) {
+            return StrictMath.cosh(((Number) args[0]).doubleValue());
+        }
+        return new EvalError(ControlFunctionRegistry.getFunctionName(this) + " expects a number");
+    }
+
+    public void write(JSONWriter writer, Properties options)
+        throws JSONException {
+
+        writer.object();
+        writer.key("description"); writer.value("Returns the hyperbolic cosine of a value");
+        writer.key("params"); writer.value("number d");
+        writer.key("returns"); writer.value("number");
+        writer.endObject();
+    }
+}

main/src/com/google/refine/expr/functions/math/Degrees.java

@@ -0,0 +1,63 @@
+/*
+
+Copyright 2010, Google Inc.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+    * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+*/
+
+package com.google.refine.expr.functions.math;
+
+import java.util.Properties;
+
+import org.json.JSONException;
+import org.json.JSONWriter;
+
+import com.google.refine.expr.EvalError;
+import com.google.refine.grel.ControlFunctionRegistry;
+import com.google.refine.grel.Function;
+
+public class Degrees implements Function {
+
+    public Object call(Properties bindings, Object[] args) {
+        if (args.length == 1 && args[0] != null && args[0] instanceof Number) {
+            return Math.toDegrees(((Number) args[0]).doubleValue());
+        }
+        return new EvalError(ControlFunctionRegistry.getFunctionName(this) + " expects a number");
+    }
+
+    public void write(JSONWriter writer, Properties options)
+        throws JSONException {
+
+        writer.object();
+        writer.key("description"); writer.value("Converts an angle from radians to degrees.");
+        writer.key("params"); writer.value("number d");
+        writer.key("returns"); writer.value("number");
+        writer.endObject();
+    }
+}

main/src/com/google/refine/expr/functions/math/Even.java

@@ -0,0 +1,68 @@
+/*
+
+Copyright 2010, Google Inc.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+    * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+*/
+
+package com.google.refine.expr.functions.math;
+
+import java.util.Properties;
+
+import org.json.JSONException;
+import org.json.JSONWriter;
+
+import com.google.refine.expr.EvalError;
+import com.google.refine.grel.ControlFunctionRegistry;
+import com.google.refine.grel.Function;
+
+public class Even implements Function {
+
+    public Object call(Properties bindings, Object[] args) {
+        if (args.length == 1 && args[0] != null && args[0] instanceof Number) {
+            return Even.RoundUpToEven(((Number) args[0]).doubleValue());
+        }
+        return new EvalError(ControlFunctionRegistry.getFunctionName(this) + " expects a number");
+    }
+
+    public static double RoundUpToEven(double d){
+        double temp = Math.ceil(d);
+        return ((temp % 2) == 0) ? temp : temp+1;
+    }
+
+    public void write(JSONWriter writer, Properties options)
+        throws JSONException {
+
+        writer.object();
+        writer.key("description"); writer.value("Rounds the number up to the nearest even integer");
+        writer.key("params"); writer.value("number d");
+        writer.key("returns"); writer.value("number");
+        writer.endObject();
+    }
+}

main/src/com/google/refine/expr/functions/math/Fact.java

@@ -0,0 +1,74 @@
+/*
+
+Copyright 2010, Google Inc.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+    * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+*/
+
+package com.google.refine.expr.functions.math;
+
+import java.util.Properties;
+
+import org.json.JSONException;
+import org.json.JSONWriter;
+
+import com.google.refine.expr.EvalError;
+import com.google.refine.grel.ControlFunctionRegistry;
+import com.google.refine.grel.Function;
+
+public class Fact implements Function {
+
+    public Object call(Properties bindings, Object[] args) {
+        if (args.length == 1 && args[0] != null && args[0] instanceof Number) {
+            return Fact.factorial(((Number) args[0]).intValue());
+        }
+        return new EvalError(ControlFunctionRegistry.getFunctionName(this) + " expects a number");
+    }
+
+    /*
+     * Calculates the factorial of an integer, i.
+     * Returns 1 for zero and negative integers.
+     */
+    public static int factorial(int i){
+        if(i <= 1)
+            return 1;
+        else
+            return i * Fact.factorial(i - 1);
+    }
+
+    public void write(JSONWriter writer, Properties options)
+        throws JSONException {
+
+        writer.object();
+        writer.key("description"); writer.value("Returns the factorial of a number");
+        writer.key("params"); writer.value("number i");
+        writer.key("returns"); writer.value("number");
+        writer.endObject();
+    }
+}

main/src/com/google/refine/expr/functions/math/Odd.java

@@ -0,0 +1,68 @@
+/*
+
+Copyright 2010, Google Inc.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+    * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+*/
+
+package com.google.refine.expr.functions.math;
+
+import java.util.Properties;
+
+import org.json.JSONException;
+import org.json.JSONWriter;
+
+import com.google.refine.expr.EvalError;
+import com.google.refine.grel.ControlFunctionRegistry;
+import com.google.refine.grel.Function;
+
+public class Odd implements Function {
+
+    public Object call(Properties bindings, Object[] args) {
+        if (args.length == 1 && args[0] != null && args[0] instanceof Number) {
+            return Odd.RoundUpToOdd(((Number) args[0]).doubleValue());
+        }
+        return new EvalError(ControlFunctionRegistry.getFunctionName(this) + " expects a number");
+    }
+
+    public static double RoundUpToOdd(double d){
+        double temp = Math.ceil(d);
+        return ((temp % 2) == 0) ? temp + 1 : temp;
+    }
+
+    public void write(JSONWriter writer, Properties options)
+        throws JSONException {
+
+        writer.object();
+        writer.key("description"); writer.value("Rounds the number up to the nearest even integer");
+        writer.key("params"); writer.value("number d");
+        writer.key("returns"); writer.value("number");
+        writer.endObject();
+    }
+}

main/src/com/google/refine/expr/functions/math/Radians.java

@@ -0,0 +1,63 @@
+/*
+
+Copyright 2010, Google Inc.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+    * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+*/
+
+package com.google.refine.expr.functions.math;
+
+import java.util.Properties;
+
+import org.json.JSONException;
+import org.json.JSONWriter;
+
+import com.google.refine.expr.EvalError;
+import com.google.refine.grel.ControlFunctionRegistry;
+import com.google.refine.grel.Function;
+
+public class Radians implements Function {
+
+    public Object call(Properties bindings, Object[] args) {
+        if (args.length == 1 && args[0] != null && args[0] instanceof Number) {
+            return Math.toRadians(((Number) args[0]).doubleValue());
+        }
+        return new EvalError(ControlFunctionRegistry.getFunctionName(this) + " expects a number");
+    }
+
+    public void write(JSONWriter writer, Properties options)
+        throws JSONException {
+
+        writer.object();
+        writer.key("description"); writer.value("Converts an angle in degrees to radians");
+        writer.key("params"); writer.value("number d");
+        writer.key("returns"); writer.value("number");
+        writer.endObject();
+    }
+}

main/src/com/google/refine/expr/functions/math/Sin.java

@@ -0,0 +1,63 @@
+/*
+
+Copyright 2010, Google Inc.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+    * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+*/
+
+package com.google.refine.expr.functions.math;
+
+import java.util.Properties;
+
+import org.json.JSONException;
+import org.json.JSONWriter;
+
+import com.google.refine.expr.EvalError;
+import com.google.refine.grel.ControlFunctionRegistry;
+import com.google.refine.grel.Function;
+
+public class Sin implements Function {
+
+    public Object call(Properties bindings, Object[] args) {
+        if (args.length == 1 && args[0] != null && args[0] instanceof Number) {
+            return Math.sin(((Number) args[0]).doubleValue());
+        }
+        return new EvalError(ControlFunctionRegistry.getFunctionName(this) + " expects a number");
+    }
+
+    public void write(JSONWriter writer, Properties options)
+        throws JSONException {
+
+        writer.object();
+        writer.key("description"); writer.value("Returns the trigonometric sine of an angle");
+        writer.key("params"); writer.value("number d");
+        writer.key("returns"); writer.value("number");
+        writer.endObject();
+    }
+}

main/src/com/google/refine/expr/functions/math/Sinh.java

@@ -0,0 +1,63 @@
+/*
+
+Copyright 2010, Google Inc.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+    * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+*/
+
+package com.google.refine.expr.functions.math;
+
+import java.util.Properties;
+
+import org.json.JSONException;
+import org.json.JSONWriter;
+
+import com.google.refine.expr.EvalError;
+import com.google.refine.grel.ControlFunctionRegistry;
+import com.google.refine.grel.Function;
+
+public class Sinh implements Function {
+
+    public Object call(Properties bindings, Object[] args) {
+        if (args.length == 1 && args[0] != null && args[0] instanceof Number) {
+            return StrictMath.sinh(((Number) args[0]).doubleValue());
+        }
+        return new EvalError(ControlFunctionRegistry.getFunctionName(this) + " expects a number");
+    }
+
+    public void write(JSONWriter writer, Properties options)
+        throws JSONException {
+
+        writer.object();
+        writer.key("description"); writer.value("Returns the hyperbolic sine of an angle");
+        writer.key("params"); writer.value("number d");
+        writer.key("returns"); writer.value("number");
+        writer.endObject();
+    }
+}

main/src/com/google/refine/expr/functions/math/Tan.java

@@ -0,0 +1,63 @@
+/*
+
+Copyright 2010, Google Inc.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+    * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+*/
+
+package com.google.refine.expr.functions.math;
+
+import java.util.Properties;
+
+import org.json.JSONException;
+import org.json.JSONWriter;
+
+import com.google.refine.expr.EvalError;
+import com.google.refine.grel.ControlFunctionRegistry;
+import com.google.refine.grel.Function;
+
+public class Tan implements Function {
+
+    public Object call(Properties bindings, Object[] args) {
+        if (args.length == 1 && args[0] != null && args[0] instanceof Number) {
+            return Math.tan(((Number) args[0]).doubleValue());
+        }
+        return new EvalError(ControlFunctionRegistry.getFunctionName(this) + " expects a number");
+    }
+
+    public void write(JSONWriter writer, Properties options)
+        throws JSONException {
+
+        writer.object();
+        writer.key("description"); writer.value("Returns the trigonometric tangent of an angle");
+        writer.key("params"); writer.value("number d");
+        writer.key("returns"); writer.value("number");
+        writer.endObject();
+    }
+}

main/src/com/google/refine/expr/functions/math/Tanh.java

@@ -0,0 +1,63 @@
+/*
+
+Copyright 2010, Google Inc.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+    * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+*/
+
+package com.google.refine.expr.functions.math;
+
+import java.util.Properties;
+
+import org.json.JSONException;
+import org.json.JSONWriter;
+
+import com.google.refine.expr.EvalError;
+import com.google.refine.grel.ControlFunctionRegistry;
+import com.google.refine.grel.Function;
+
+public class Tanh implements Function {
+
+    public Object call(Properties bindings, Object[] args) {
+        if (args.length == 1 && args[0] != null && args[0] instanceof Number) {
+            return StrictMath.tanh(((Number) args[0]).doubleValue());
+        }
+        return new EvalError(ControlFunctionRegistry.getFunctionName(this) + " expects a number");
+    }
+
+    public void write(JSONWriter writer, Properties options)
+        throws JSONException {
+
+        writer.object();
+        writer.key("description"); writer.value("Returns the hyperbolic tangent of a value");
+        writer.key("params"); writer.value("number d");
+        writer.key("returns"); writer.value("number");
+        writer.endObject();
+    }
+}

main/src/com/google/refine/grel/ControlFunctionRegistry.java

@@ -59,18 +59,34 @@ import com.google.refine.expr.functions.booleans.Or;
 import com.google.refine.expr.functions.date.DatePart;
 import com.google.refine.expr.functions.date.Inc;
 import com.google.refine.expr.functions.date.Now;
+import com.google.refine.expr.functions.math.ACos;
+import com.google.refine.expr.functions.math.ASin;
+import com.google.refine.expr.functions.math.ATan;
+import com.google.refine.expr.functions.math.ATan2;
 import com.google.refine.expr.functions.math.Abs;
 import com.google.refine.expr.functions.math.Ceil;
+import com.google.refine.expr.functions.math.Combin;
+import com.google.refine.expr.functions.math.Cos;
+import com.google.refine.expr.functions.math.Cosh;
+import com.google.refine.expr.functions.math.Degrees;
+import com.google.refine.expr.functions.math.Even;
 import com.google.refine.expr.functions.math.Exp;
+import com.google.refine.expr.functions.math.Fact;
 import com.google.refine.expr.functions.math.Floor;
 import com.google.refine.expr.functions.math.Ln;
 import com.google.refine.expr.functions.math.Log;
 import com.google.refine.expr.functions.math.Max;
 import com.google.refine.expr.functions.math.Min;
 import com.google.refine.expr.functions.math.Mod;
+import com.google.refine.expr.functions.math.Odd;
 import com.google.refine.expr.functions.math.Pow;
+import com.google.refine.expr.functions.math.Radians;
 import com.google.refine.expr.functions.math.Round;
+import com.google.refine.expr.functions.math.Sin;
+import com.google.refine.expr.functions.math.Sinh;
 import com.google.refine.expr.functions.math.Sum;
+import com.google.refine.expr.functions.math.Tan;
+import com.google.refine.expr.functions.math.Tanh;
 import com.google.refine.expr.functions.strings.Chomp;
 import com.google.refine.expr.functions.strings.Contains;
 import com.google.refine.expr.functions.strings.Diff;
@@ -212,9 +228,21 @@ public class ControlFunctionRegistry {
         registerFunction("inc", new Inc());
         registerFunction("datePart", new DatePart());
 
+        registerFunction("acos", new ACos());
+        registerFunction("asin", new ASin());
+        registerFunction("atan", new ATan());
+        registerFunction("atan2", new ATan2());
+        registerFunction("cos", new Cos());
+        registerFunction("cosh", new Cosh());
+        registerFunction("sin", new Sin());
+        registerFunction("sinh", new Sinh());
+        registerFunction("tan", new Tan());
+        registerFunction("tanh", new Tanh());
         registerFunction("round", new Round());
         registerFunction("floor", new Floor());
         registerFunction("ceil", new Ceil());
+        registerFunction("even", new Even());
+        registerFunction("odd", new Odd());
         registerFunction("abs", new Abs());
         registerFunction("mod", new Mod());
         registerFunction("max", new Max());
@@ -224,6 +252,10 @@ public class ControlFunctionRegistry {
         registerFunction("pow", new Pow());
         registerFunction("exp", new Exp());
         registerFunction("sum", new Sum());
+        registerFunction("fact", new Fact());
+        registerFunction("comb", new Combin());
+        registerFunction("degrees", new Degrees());
+        registerFunction("radians", new Radians());
 
         registerFunction("and", new And());
         registerFunction("or", new Or());

main/src/com/google/refine/grel/Parser.java

@@ -129,14 +129,14 @@ public class Parser {
 
     /**
      *  <term> := <factor>
-     *          | <term> [ "*" "/" ] <factor>
+     *          | <term> [ "*" "/" "%" ] <factor>
      */
     protected Evaluable parseTerm() throws ParsingException {
         Evaluable factor = parseFactor();
 
         while (_token != null &&
                 _token.type == TokenType.Operator &&
-                "*/".indexOf(_token.text) >= 0) {
+                "*/%".indexOf(_token.text) >= 0) {
 
             String op = _token.text;
 
@@ -202,6 +202,9 @@ public class Parser {
 
             if (_token == null || _token.type != TokenType.Delimiter || !_token.text.equals("(")) {
                 eval = "null".equals(text) ? new LiteralExpr(null) : new VariableExpr(text);
+            } else if( "PI".equals(text) ) {
+                eval = new LiteralExpr(Math.PI);
+                next(false);
             } else {
                 Function f = ControlFunctionRegistry.getFunction(text);
                 Control c = ControlFunctionRegistry.getControl(text);

main/src/com/google/refine/grel/Scanner.java

@@ -267,7 +267,7 @@ public class Scanner {
 
             detail = "Regex not properly closed";
             // fall through
-        } else if ("+-*/.".indexOf(c) >= 0) { // operator
+        } else if ("+-*/.%".indexOf(c) >= 0) { // operator
             _index++;
 
             return new Token(

main/src/com/google/refine/grel/ast/OperatorCallExpr.java

@@ -74,6 +74,8 @@ public class OperatorCallExpr implements Evaluable {
                         return n1 * n2;
                     } else if ("/".equals(_op)) {
                         return n1 / n2;
+                    } else if ("%".equals(_op)) {
+                        return n1 % n2;
                     } else if (">".equals(_op)) {
                         return n1 > n2;
                     } else if (">=".equals(_op)) {
@@ -99,6 +101,8 @@ public class OperatorCallExpr implements Evaluable {
                         return n1 * n2;
                     } else if ("/".equals(_op)) {
                         return n1 / n2;
+                    } else if ("%".equals(_op)) {
+                        return n1 % n2;
                     } else if (">".equals(_op)) {
                         return n1 > n2;
                     } else if (">=".equals(_op)) {