Reorganized File Structure

Added Documentation

MathKit/MPSumFunction.m

@@ -0,0 +1,45 @@
+//
+//  MPSumFunction.m
+//  MathPad
+//
+//  Created by Kim Wittenburg on 22.04.14.
+//  Copyright (c) 2014 Kim Wittenburg. All rights reserved.
+//
+
+#import "MPSumFunction.h"
+
+#import "MPSumFunctionTerm.h"
+#import "MPExpression.h"
+
+
+
+@implementation MPSumFunction
+
+
+MPFunctionAccessorImplementation(StartExpression, _startExpression)
+MPFunctionAccessorImplementation(TargetExpression, _targetExpression)
+MPFunctionAccessorImplementation(SumExpression, _sumExpression)
+
+
+- (NSArray *)childrenAccessors
+{
+    return @[@"startExpression", @"targetExpression", @"sumExpression"];
+}
+
+- (BOOL)expectsVariableDefinitionInChildAtIndex:(NSUInteger)index
+{
+    return index == 0;
+}
+
+- (Class)functionTermClass
+{
+    return [MPSumFunctionTerm class];
+}
+
+
+- (NSString *)description
+{
+    return [NSString stringWithFormat:@"Sum(From: %@; To: %@; Using: %@)", self.startExpression, self.targetExpression, self.sumExpression];
+}
+
+@end