Correct answer - comparing strings - ios

Question

I'm building my own alternative to the Levenshtein distance to train myself in objective-c. This class will get a few sentences, only 2 during initial testing and return how many percent correct the sentence is. How many percent matches with the "correct sentence".
Basically what it does is it gets 2 sentences, (only 2 words during initial testing really) and calculates. But I get some strange NSLog's.
If I enter 1989 and 199 it'll return 75% correct - which is the correct answer. However, if I enter "orange" and "oange" - it returns 50% correct when correct is 83% (right??)
This is the code calling the method:
-(void)compare {
// Take each and every sentence from the users source and check it against the other sources. If it contains 2 or more words/numbers that are equal, i'll get "investigated" further
NSMutableArray *userSentences = [[MyManager sharedManager] contentSentencesList];
NSMutableArray *serverSentences = [NSMutableArray arrayWithArray:getSentencesFromText(serverText)];
// Sample sentences
[userSentences insertObject:#"oange" atIndex:userSentences.count];
[serverSentences insertObject:#"orange" atIndex:serverSentences.count];
// For-statement integers
int i = 0;
int b = 0;
for (i = 0; i < userSentences.count; i++) {
// Check first sentence
NSString *userSentence;
NSString *serverSentence;
// Check similarity of the two sentences, get percent and add to centerPercent
for (b = 0; b < serverSentences.count; b++) {
// Compare sentences
userSentence = userSentences[i];
serverSentence = serverSentences[b];
// Compare sentences with custom class
// Initialize Distance class
SourcerDistance *wordDistance = [[SourcerDistance alloc] init];
// Create resultPercent integer and calculate it
int resultPercent = [wordDistance distanceBetween:userSentence serverSentence:serverSentence];
NSLog(#"%#%d", #"FinishViewController result: ", resultPercent);
// Add resultPercent to averagePrecent and increase averagPercentToDivide by 1
centerPercent = centerPercent + resultPercent;
centerPercentToDivide++;
}
// Set and display resultoppositeSpelling
// averagePercent = centerPercent / centerPercentToDivide;
// Use an integer to remove decimals
[self presentResult];
}
}
and this is the other class:
#import "SourcerDistance.h"
#implementation SourcerDistance
-(int)distanceBetween:(NSString *)userSentence serverSentence:(NSString *)serverSentence {
// Declare the 2 arrays containing all the words from the user's source and the developer's source
NSArray *developerSourceSentence = [self getWords:serverSentence];
NSArray *userSourceSentence = [self getWords:userSentence];
// Declare variables that'll be use for for-statements
int developerWordsLoop = developerSourceSentence.count;
int userWordsLoop = userSourceSentence.count;
// Declare variables required for matching (average of all words)
float centerPercent = 0; // This is for ALL words in total
float centerPercentToDivide = 0; // This is for all words in total
// Single-word variables
float totalCharacters = 0;
float matchingCharacters = 0;
float percentMatchingSingleWord = 0;
NSLog(#"%#%d", #"userSourceSentenceCount: ", userSourceSentence.count);
NSLog(#"%#%d", #"developerSourceSentenceCount: ", developerSourceSentence.count);
// Loop through all of the user words
for (userWordsLoop = 0; userWordsLoop < userSourceSentence.count; userWordsLoop++) {
// Loop through all of the developer words
for (developerWordsLoop = 0; developerWordsLoop < developerSourceSentence.count; developerWordsLoop++) {
// Declare variables that contain all the characters of the user- and developer-words
NSMutableArray *userCharacters = [self getCharacters:userSourceSentence[userWordsLoop]];
NSMutableArray *developerCharacters = [self getCharacters:developerSourceSentence[developerWordsLoop]];
// Compare characters
matchingCharacters = [self compareCharacters:userCharacters developerCharacters:developerCharacters];
// Set the variables
totalCharacters = developerCharacters.count;
percentMatchingSingleWord = matchingCharacters / totalCharacters * 100;
NSLog(#"%#%f", #"totalCharacters", totalCharacters);
NSLog(#"%#%f", #"matchingCharacters", matchingCharacters);
NSLog(#"%#%f", #"iterate", percentMatchingSingleWord);
centerPercent = centerPercent + percentMatchingSingleWord;
centerPercentToDivide++;
}
}
// Declare variables used with final result
float finalPercentFloat = 0;
int finalPercent = 0;
NSLog(#"%#%f", #"centerPercent: ", centerPercent);
NSLog(#"%#%f", #"centerPercentToDivide: ", centerPercentToDivide);
finalPercentFloat = centerPercent/centerPercentToDivide;
NSLog(#"%#%f", #"finalPercent: ", finalPercentFloat);
finalPercent = (int)finalPercentFloat;
return finalPercent;
}
-(float)compareCharacters:(NSMutableArray *)userCharacters developerCharacters:(NSMutableArray *)developerCharacters {
// Declare result variables and other required variables
float matchingCharacters;
int userCharactersLoop = 0;
int developerCharactersLoop = 0;
// Loop through all of the userCharacters
for (userCharactersLoop = 0; userCharactersLoop < userCharacters.count; userCharactersLoop++) {
// Loop through all of the developerCharacters
for (developerCharactersLoop = 0; developerCharactersLoop < developerCharacters.count; developerCharactersLoop++) {
// Match every character here
if ([userCharacters[userCharactersLoop] isEqualToString:developerCharacters[developerCharactersLoop]]) {
// Increase matchingCharacters
matchingCharacters++;
} else {
// Do nothing
}
}
}
// Return result variable
return matchingCharacters;
}
-(NSArray *)getWords:(NSString *)sentence {
// Get words of sentence from developer-source
NSArray *sentenceWords;
NSString *serverSentenceToRead = sentence;
sentenceWords = [serverSentenceToRead componentsSeparatedByCharactersInSet:
[NSCharacterSet characterSetWithCharactersInString:#":;.!? "]
];
// Return developer words
return sentenceWords;
}
-(NSMutableArray *)getCharacters:(NSString *)word {
NSMutableArray *wordCharacters = [[NSMutableArray alloc] initWithCapacity:[word length]];
for (int i=0; i < [word length]; i++) {
NSString *ichar = [NSString stringWithFormat:#"%c", [word characterAtIndex:i]];
[wordCharacters addObject:ichar];
}
// Return the characters of the word
return wordCharacters;
}
#end
NSLog:
2014-09-03 20:22:32.015 Sourcer[27532:60b] userSourceSentenceCount: 1
2014-09-03 20:22:32.017 Sourcer[27532:60b] developerSourceSentenceCount: 1
2014-09-03 20:22:32.018 Sourcer[27532:60b] totalCharacters6.000000
2014-09-03 20:22:32.018 Sourcer[27532:60b] matchingCharacters3.001519
2014-09-03 20:22:32.019 Sourcer[27532:60b] iterate50.025322
2014-09-03 20:22:32.020 Sourcer[27532:60b] centerPercent: 50.025322
2014-09-03 20:22:32.021 Sourcer[27532:60b] centerPercentToDivide: 1.000000
2014-09-03 20:22:32.021 Sourcer[27532:60b] finalPercent: 50.025322
2014-09-03 20:22:32.022 Sourcer[27532:60b] FinishViewController result: 50
2014-09-03 20:22:32.022 Sourcer[27532:60b] averagePercent (float): 50.000000
What am I doing wrong here? Is it possible for anyone to understand the code and help me find out what's wrong? There's something odd about this algorithm
Thanks a lot!
(I know I'm kinda reinventing the wheel, but I want to try :))
Sincerely,
Erik