NSInteger to Word number conversion

Easy conversion between NSInteger and Word.
You need:
- http://objective-c-functions.blogspot.com/2013/08/int-to-hex-number-conversion.html
- http://objective-c-functions.blogspot.com/2013/08/hex-to-int-number-conversion.html


/** Convert an int to a Word defined by a low byte and a high byte.

 @param intVal Integer value.
 @return Returns an array in which first item is the low byte and second item is the high byte.
 @see intFromWordWithLowByte:highByte:

 */
+ (NSArray *)highLowBytesFromInteger:(NSInteger)intVal {

    NSString *hexVal = [[LMFunctions hexFromInt:intVal] substringFromIndex:2]; // Remove "0x".
    NSMutableString *prefix = [[NSMutableString alloc] initWithString:@""];

    NSInteger length = hexVal.length;
    if (length < 4) {
        for (NSInteger i=0; i<4-length; i++) {
            [prefix appendString:@"0"];
        }
    }

    hexVal = [NSString stringWithFormat:@"%@%@", prefix, hexVal];

    NSString *hexValHigh    = [hexVal substringToIndex:2];
    NSString *hexValLow        = [hexVal substringFromIndex:(hexVal.length - 2)];

    Byte bH = [LMFunctions intFromHex:hexValHigh];
    Byte bL = [LMFunctions intFromHex:hexValLow];

    return [NSArray arrayWithObjects:[NSNumber numberWithInteger:bH], [NSNumber numberWithInteger:bL], nil];
}


Download the ready-for-use source file (.m) of NSInteger to Word number conversion

Word to NSInteger number conversion

Intermediate function that converts a Word into a NSInteger.
You need:
- http://objective-c-functions.blogspot.com/2013/08/hex-to-int-number-conversion.html

/** Convert a Word to an int.

 @param lowByte The low byte of the word.
 @param highByte The high byte of the word.
 @return Returns the integer value of the word.
 @see highLowBytesFromInteger:

 */
+ (NSInteger)intFromWordWithLowByte:(Byte)lowByte highByte:(Byte)highByte {

    NSString *startHexAddressHigh    = [NSString stringWithFormat:@"0x%X", highByte];
    NSString *startHexAddressLow    = [NSString stringWithFormat:@"0x%X", lowByte];

    NSInteger res = [LMFunctions intFromHex:startHexAddressHigh] * 16 * 16;
    res += [LMFunctions intFromHex:startHexAddressLow];

    return res;
}


Download the ready-for-use source file (.m) of Word to NSInteger number conversion

Add zeros to a digit number

So you have a number and want to add zeros to it? Check out my convenient Objective-C method.
You need:
- http://objective-c-functions.blogspot.com/2013/08/nsinteger-to-nsstring.html


/** Returns a two digits number.

 Prepends "0" if the number is between 0 and 9.

 @param n Integer to manage.
 @return Returns a string representing the two-digits number.
 @see threeDigits:

 */
+ (NSString *)twoDigits:(NSInteger)n {
    NSString *ret = [LMFunctions stringFromInt:n];
    if (n>=0 && n<10) {
        ret = [NSString stringWithFormat:@"0%d", n];
    }
    return ret;
}


Download the ready-for-use source file (.m) of Add zeros to a digit number

Hex to Int number conversion

Hexadecimal-to-NSInteger made easy with this helpful function.


/** Convert a hex to an int.

 @param val Hexadecimal value as string.
 @return Returns the integer value.
 @see isHexadecimalNumber:
 @see hexFromInt:

 */
+ (NSInteger)intFromHex:(NSString *)val {
    NSUInteger res = 0;
    NSScanner *scanner = [NSScanner scannerWithString:val];
    [scanner scanHexInt:&res];
    return (NSInteger)res;
}


Download the ready-for-use source file (.m) of Hex to Int number conversion

Int to Hex number conversion

A simple but helpful function for int-to-hex conversion.


/** Convert an int to a hex.

 @param val Integer value.
 @return Returns the hexadecimal value as string.
 @see isHexadecimalNumber:
 @see intFromHex:

 */
+ (NSString *)hexFromInt:(NSInteger)val {
    return [NSString stringWithFormat:@"0x%X", val];
}


Download the ready-for-use source file (.m) of Int to Hex number conversion

NSInteger to NSString

A convenient shortcut of [NSString stringWithFormat:] for NSInteger values.


/** Convert an int to its string representation.

 @param n Integer to convert.
 @return Returns the string value of the number.
 @see stringFromInt:
 @see stringFromFloat:usingSeparatorForDecimal:
 @see stringFromBool:ofType:

 */
+ (NSString *)stringFromInt:(NSInteger)n {
    return [NSString stringWithFormat:@"%i",n];
}


Download the ready-for-use source file (.m) of NSInteger to NSString

Greater Common Divisor (GCD) between 2 numbers

This time we're considering an easy math problem: the Greater Common Divisor between two integers.


/** Compute the Greater Common Divisor (GCD) for two numbers.

 @param num1 First number.
 @param num2 Second number.
 @return Returns the Greater Common Divisor (GCD).

 */
+ (NSInteger)greaterCommonDivisorForNumber1:(NSInteger)num1 andNumber2:(NSInteger)num2 {
    if (num1 < 0 || num2 < 0) {
        LogError(@"Numbers are negative. Cannot compute GCD");
    } else {
        NSInteger temp = num1 % num2;
        while (temp > 0) {
            num1 = num2;
            num2 = temp;
            temp = num1 % num2;
        }
    }
    return num2;
}


Download the ready-for-use source file (.m) of Greater Common Divisor (GCD) between 2 numbers

Hex to int conversion (full string)

A pure C function that will do the hex-2-int conversion.
This function takes the whole hexadecimal string.
You need:
- http://objective-c-functions.blogspot.com/2013/07/hex-to-int-conversion-single-char.html


/** Convert a hex number to an int.

 @param p Characters of the hexadecimal value.
 @return Returns the integer value.

 */
int hex2(char *p) {
    int i;
    unsigned char c;
    i = hex(*p++);
    if (i < 0) return i;
    c = (i << 4);
    i = hex(*p);
    if (i < 0) return i;
    return c | i;
}


Download the ready-for-use source file (.m) of Hex to int conversion (full string)

Hex to int conversion (single char)

A pure C function that will do the hex-2-int conversion.
This function takes only a single char.


/** Convert a hex char to an int.

 @param c Single character representing a hexadecimal char.
 @return Returns the integer value.

 */
int hex(char c) {
    if ('0' <= c && c <= '9') return c - '0';
    if ('a' <= c && c <= 'f') return c - 'a' + 10;
    if ('A' <= c && c <= 'F') return c - 'A' + 10;
    return -1;
}


Download the ready-for-use source file (.m) of Hex to int conversion (single char)

Int to binary

This convenient method converts an integer to a binary number.


/** Convert an int to a binary.

 @param val Integer value.
 @return Returns the binary value as string.

 */
+ (NSString *)binaryFromInt:(NSInteger)val {
    NSMutableString *str = [NSMutableString string];
    for (NSInteger num = val; num > 0; num >>= 1) {
        [str insertString:((num & 1) ? @"1" : @"0") atIndex:0]; // Prepend 0 or 1, depending on the bit.
    }
    return str;
}


Download the ready-for-use source file (.m) of Int to binary