Corrected MPExpression -itemAtIndex:referenceFrame:MPSymbolReferenceFrame

Corrected Deformed Number Format
Added "arcsin", "arccos", "arctan", "lg", "log", "ln" Elementary Functions

MathPad/MPElementaryFunctionTerm.m

@@ -39,17 +39,21 @@
         } else if ([function isEqualToString:@"tan"]) {
             func = &tan;
             takesArc = YES;
-        } else if ([function isEqualToString:@"asin"]) {
+        } else if ([function isEqualToString:@"asin"] || [function isEqualToString:@"arcsin"]) {
             func = &asin;
             returnsArc = YES;
-        } else if ([function isEqualToString:@"acos"]) {
+        } else if ([function isEqualToString:@"acos"] || [function isEqualToString:@"arccos"]) {
             func = &acos;
             returnsArc = YES;
-        } else if ([function isEqualToString:@"atan"]) {
+        } else if ([function isEqualToString:@"atan"] || [function isEqualToString:@"arctan"]) {
             func = &atan;
             returnsArc = YES;
+        } else if ([function isEqualToString:@"lg"] || [function isEqualToString:@"log"]) {
+            func = &log10;
+        } else if ([function isEqualToString:@"ln"]) {
+            func = &log;
         } else {
-            NSAssert(true, @"function must be one of (sin, cos, tan, asin, acos, atan).");
+            NSAssert(true, @"function must be one of (sin, cos, tan, asin, acos, atan, lg, log, ln).");
         }
         [self setFunction:func
             takesArcValue:takesArc

MathPad/MPExpression.m

@@ -269,18 +269,17 @@ NSString *const MPIllegalElementExceptionElementKey = @"MPIllegalElementExceptio
             
         case MPSymbolReferenceFrame:
         {
-            NSUInteger location = 0;
+            NSUInteger offsetInElement;
-            NSUInteger elementIndex = 0;
+            NSUInteger elementIndex = [self convertIndex:anIndex
-            id <MPExpressionElement> element = nil;
+                                      fromReferenceFrame:MPSymbolReferenceFrame
-            while (location < anIndex) {
+                                        toReferenceFrame:MPElementReferenceFrame
-                element = _elements[elementIndex++];
+                                                  offset:&offsetInElement];
-                location += element.length;
+            id<MPExpressionElement> element = [self elementAtIndex:elementIndex];
-            }
+            if ([element isFunction]) {
-            if (location == anIndex && element.isFunction) {
                 return element;
+            } else {
+                return [((NSString *)element) substringWithRange:NSMakeRange(offsetInElement, 1)];
             }
-            NSUInteger indexInString = location - element.length + anIndex;
-            return [((NSString *)element) substringWithRange:NSMakeRange(indexInString, 1)];
         }
             
         case MPTokenReferenceFrame:

MathPad/MPExpressionLayout.m

@@ -259,8 +259,9 @@
     // Set the text matrix
     CGContextSetTextMatrix(context, CGAffineTransformIdentity);
     
-    // Track the x position
+    // Track the x position and the bounds of the last element
     CGFloat x = 0;
+    NSRect lastElementBounds = NSMakeRect(0, kMPEmptyBoxYOrigin, kMPEmptyBoxWidth, kMPEmptyBoxHeight);
     
     for (NSUInteger index = 0; index < self.expression.countElements; index++) {
         // The current element
@@ -279,17 +280,16 @@
             CTLineDraw(line, context);
             
             CFRelease(line);
-            
-            if (index < self.expression.countElements-1 && [[self.expression elementAtIndex:index+1] isKindOfClass:[MPPowerFunction class]]) {
-                MPPowerFunctionLayout *layout = (MPPowerFunctionLayout *)[self childLayoutAtIndex:index+1];
-                layout.baseBounds = elementBounds;
-            }
         } else {
             // Let the child layout draw itself
             MPLayout *layout = [self childLayoutAtIndex:index];
+            if ([layout isKindOfClass:[MPPowerFunctionLayout class]]) {
+                ((MPPowerFunctionLayout *)layout).baseBounds = lastElementBounds;
+            }
             [layout drawAtPoint:NSMakePoint(x, 0)];
         }
         x += elementBounds.size.width;
+        lastElementBounds = elementBounds;
     }
     CGContextRestoreGState(context);
 }

MathPad/MPExpressionTokenizer.m

@@ -49,9 +49,9 @@
     NSString *regexStringFormat = @"\\A(?:"
                             @"([\\*∙⋅])|"
                             @"([+-](?:\\s*[+-])*)|"
-                            @"((?:\\d+%@(?!\\d+))|(?:(?:\\d*%@){2,}\\d*)|%@)|" // Substitute with decimal separator 3 times
+                            @"((?:\\d+%@(?!\\d+))|(?:(?:\\d*%@){2,}\\d*)|%@(?!\\d+))|" // Substitute with decimal separator 3 times
                             @"((?:\\d+(?:%@\\d+)?)|(?:%@\\d+))|" // Substitute with decimal separator 2 times
-                            @"(sin|cos|tan|asin|acos|atan)|"
+                            @"(sin|cos|tan|asin|arcsin|acos|arccos|atan|arctan|lg|log|ln)|"
                             @"([A-Za-z])|"
                             @"(!)|"
                             @"(=)|"

MathPad/MPExpressionView.m

@@ -16,6 +16,7 @@
 #import "MPParenthesisFunction.h"
 #import "MPFractionFunction.h"
 
+#import "MPToken.h"
 #import "MPRangePath.h"
 #import "MPMathRules.h"
 
@@ -648,6 +649,10 @@
         [self insertParenthesisFunction:nil];
         return;
     }
+    if ([characters isEqualToString:@")"]) {
+        [self insertClosingParenthesis];
+        return;
+    }
     if (theEvent.keyCode == 10) {
         [self insertPowerFunction];
         return;
@@ -692,6 +697,29 @@
     self.selection = MPMakeRangePath([[functionPath indexPathByAddingIndex:0] indexPathByAddingIndex:0], self.selection.length);
 }
 
+- (void)insertClosingParenthesis
+{
+    if (self.selection.length > 0) {
+        [self insertParenthesisFunction:self];
+    } else {
+        NSIndexPath *currentPath = [[self.selection.location indexPathByRemovingLastIndex] indexPathByRemovingLastIndex];
+        while (currentPath.length > 0) {
+            id element = [self.expressionStorage elementAtIndexPath:currentPath];
+            if ([element isKindOfClass:[MPParenthesisFunction class]]) {
+                MPExpression *targetExpression = [self.expressionStorage elementAtIndexPath:[currentPath indexPathByRemovingLastIndex]];
+                NSUInteger selectedIndex = currentPath.lastIndex + 1;
+                selectedIndex = [targetExpression convertIndex:selectedIndex
+                                            fromReferenceFrame:MPElementReferenceFrame
+                                              toReferenceFrame:MPSymbolReferenceFrame];
+                self.selection = MPMakeRangePath([currentPath indexPathByReplacingLastIndexWithIndex:selectedIndex], 0);
+                break;
+            } else {
+                currentPath = [[currentPath indexPathByRemovingLastIndex] indexPathByRemovingLastIndex];
+            }
+        }
+    }
+}
+
 - (void)insertPowerFunction
 {
     MPExpression *selectedElementsExpression = [self.expressionStorage subexpressionWithRangePath:self.selection
@@ -712,6 +740,41 @@
 
 - (void)insertFractionFunction
 {
+    if (self.selection.length == 0) {
+        MPExpression *targetExpression = [self.expressionStorage elementAtIndexPath:[self.selection.location indexPathByRemovingLastIndex]];
+        NSInteger index = self.selection.location.lastIndex;
+        NSRange nominatorSymbols = NSMakeRange(index, 0);
+        while (--index >= 0) {
+            id<MPExpressionElement> symbol = [targetExpression symbolAtIndex:index];
+            if ([symbol isString]) {
+                NSUInteger tokenIndex = [targetExpression convertIndex:index
+                                                    fromReferenceFrame:MPSymbolReferenceFrame
+                                                      toReferenceFrame:MPTokenReferenceFrame];
+                id<MPToken> token = [targetExpression tokenAtIndex:tokenIndex];
+                if (token.tokenType == MPNumberToken || token.tokenType == MPVariableToken || token.tokenType == MPElementaryFunctionToken) {
+                    nominatorSymbols.location--;
+                    nominatorSymbols.length++;
+                } else {
+                    break;
+                }
+            } else if (nominatorSymbols.length == 0) {
+                nominatorSymbols.location--;
+                nominatorSymbols.length++;
+            } else {
+                break;
+            }
+        }
+        MPExpression *nominatorExpression = [targetExpression subexpressionWithRange:nominatorSymbols
+                                                                      referenceFrame:MPSymbolReferenceFrame];
+        MPFractionFunction *function = [[MPFractionFunction alloc] init];
+        function.nominatorExpression = nominatorExpression;
+        [targetExpression replaceItemsInRange:nominatorSymbols referenceFrame:MPSymbolReferenceFrame withElements:@[function]];
+        NSUInteger functionElementIndex = [targetExpression convertIndex:nominatorSymbols.location
+                                                      fromReferenceFrame:MPSymbolReferenceFrame
+                                                        toReferenceFrame:MPElementReferenceFrame];
+        NSUInteger selectedSubexpression = nominatorSymbols.length == 0 ? 0 : 1;
+        self.selection = MPMakeRangePath([[[self.selection.location indexPathByReplacingLastIndexWithIndex:functionElementIndex] indexPathByAddingIndex:selectedSubexpression] indexPathByAddingIndex:0], 0);
+    } else {
         MPExpression *selectedElementsExpression = [self.expressionStorage subexpressionWithRangePath:self.selection
                                                                                        referenceFrame:MPSymbolReferenceFrame];
         MPFractionFunction *function = [[MPFractionFunction alloc] init];
@@ -726,6 +789,7 @@
         NSIndexPath *functionPath = [self.selection.location indexPathByReplacingLastIndexWithIndex:functionElementIndex];
         self.selection = MPMakeRangePath([[functionPath indexPathByAddingIndex:0] indexPathByAddingIndex:0], 0);
     }
+}
 
 - (void)insertNewline:(id)sender
 {

MathPad/MPFractionFunctionLayout.m

@@ -36,7 +36,7 @@
 
 - (NSIndexSet *)indexesOfRemainingChildren
 {
-    return [NSIndexSet indexSetWithIndexesInRange:NSMakeRange(0, 1)];
+    return [NSIndexSet indexSetWithIndexesInRange:NSMakeRange(0, 2)];
 }
 
 - (NSPoint)offsetOfChildLayoutAtIndex:(NSUInteger)index

MathPad/MPLayout.m

@@ -53,7 +53,7 @@
 
 - (NSFont *)specialFontWithSize:(CGFloat)size
 {
-    return [NSFont fontWithName:@"CMU Sans Serif Oblique"
+    return [NSFont fontWithName:@"CMU Serif Italic"
                            size:size];
 }