FormatUtil (ELKI: Environment for DeveLoping KDD-Applications Supported by Index-Structures)

java.lang.Object
- de.lmu.ifi.dbs.elki.utilities.FormatUtil

```
public final class FormatUtil
extends Object
```
Utility methods for output formatting of various number objects

Field Summary

Fields
Modifier and Type	Field and Description
`private static NumberFormatException`	`EMPTY_STRING` Preallocated exceptions.
`private static NumberFormatException`	`EXPONENT_OVERFLOW` Preallocated exceptions.
`private static int`	`INFINITY_LENGTH` Length of pattern
`private static char[]`	`INFINITY_PATTERN` Infinity pattern, with any capitalization
`private static NumberFormatException`	`INVALID_EXPONENT` Preallocated exceptions.
`private static int`	`MAX_INT_OVERFLOW` Maximum integer that we can process without overflowing.
`private static long`	`MAX_LONG_OVERFLOW` Maximum long that we can process without overflowing.
`static String`	`NEWLINE` The system newline setting.
`static NumberFormat`	`NF` Dynamic number formatter, but with language constraint.
`static NumberFormat`	`NF0` Number Formatter (0 digits) for output purposes.
`static NumberFormat`	`NF2` Number Formatter (2 digits) for output purposes.
`static NumberFormat`	`NF3` Number Formatter (3 digits) for output purposes.
`static NumberFormat`	`NF4` Number Formatter (4 digits) for output purposes.
`static NumberFormat`	`NF6` Number Formatter (6 digits) for output purposes.
`static NumberFormat`	`NF8` Number Formatter (8 digits) for output purposes.
`static String`	`NONBREAKING_SPACE` Non-breaking unicode space character.
`private static NumberFormatException`	`NOT_A_NUMBER` Preallocated exceptions.
`private static NumberFormatException`	`PRECISION_OVERFLOW` Preallocated exceptions.
`private static char[]`	`SPACEPADDING` Buffer for whitespace padding.
`private static int[]`	`TIME_UNIT_DIGITS` The number of digits used for formatting
`private static String[]`	`TIME_UNIT_NAMES` The strings used in serialization
`private static long[]`	`TIME_UNIT_SIZES` The time unit sizes: ms, s, m, h, d; all in ms.
`private static NumberFormatException`	`TRAILING_CHARACTERS` Preallocated exceptions.
`private static String`	`WHITESPACE_BUFFER` Whitespace.
`private static char[]`	`ZEROPADDING` Buffer for zero padding.

Constructor Summary

Constructors
Constructor and Description

FormatUtil()

Constructors
Constructor and Description
`FormatUtil()`

Method Summary

Methods
Modifier and Type	Method and Description
`static StringBuilder`	`appendSpace(StringBuilder buf, int spaces)` Append whitespace to a buffer.
`static StringBuilder`	`appendZeros(StringBuilder buf, int zeros)` Append zeros to a buffer.
`static int`	`findSplitpoint(String s, int width)` Find the first space before position w or if there is none after w.
`static String`	`format(boolean b)` Formats the boolean b.
`static String`	`format(boolean[] b, String sep)` Formats the boolean array b with ',' as separator.
`static StringBuilder`	`format(boolean b, StringBuilder buf)` Format a boolean value as string "true" or "false".
`static String`	`format(byte[] a)` Formats the byte array a for printing purposes.
`static String`	`format(Collection<String> d, String sep)` Formats the String collection with the specified separator.
`static String`	`format(double[] d)` Formats the double array d with ', ' as separator and 2 fraction digits.
`static String`	`format(double[][] d)` Formats the double array d with ',' as separator and 2 fraction digits.
`static String`	`format(double[][] d, String sep1, String sep2, NumberFormat nf)` Formats the array of double arrays d with 'the specified separators and fraction digits.
`static String`	`format(double[] d, NumberFormat nf)` Formats the double array d with the specified number format.
`static String`	`format(double[] d, String sep)` Formats the double array d with the specified separator.
`static String`	`format(double[] d, String sep, NumberFormat nf)` Formats the double array d with the specified number format.
`static String`	`format(float[] f)` Formats the float array f with ',' as separator and 2 fraction digits.
`static String`	`format(float[] d, String sep, NumberFormat nf)` Formats the double array d with the specified number format.
`static String`	`format(int[] a)` Formats the int array a for printing purposes.
`static String`	`format(int[] a, String sep)` Formats the int array a for printing purposes.
`static String`	`format(int dim, long[] bitSet)` Returns a string representation of the specified bit set.
`static StringBuilder`	`format(int i, StringBuilder buf)` Format an integer value as decimal.
`static String`	`format(long[] a)` Formats the long array a for printing purposes.
`static String`	`format(long[] bitSet, int dim, String sep)` Returns a string representation of the specified bit set.
`static StringBuilder`	`format(long i, StringBuilder buf)` Format a long value as decimal.
`static String`	`format(Matrix m)` returns String-representation of Matrix.
`static String`	`format(Matrix m, int w, int d)` Returns a string representation of this matrix.
`static String`	`format(Matrix m, NumberFormat nf)` returns String-representation of Matrix.
`static String`	`format(Matrix m, String pre)` Returns a string representation of this matrix.
`static String`	`format(Matrix m, String pre, NumberFormat nf)` Returns a string representation of this matrix.
`static String`	`format(String[] d, String sep)` Formats the string array d with the specified separator.
`static String`	`format(Vector m)` Returns String-representation of Vector.
`static String`	`format(Vector v, int w, int d)` Returns a string representation of this matrix.
`static String`	`format(Vector m, NumberFormat nf)` returns String-representation of Vector.
`static String`	`format(Vector v, String pre)` Returns a string representation of this matrix.
`static StringBuilder`	`formatBit(boolean b, StringBuilder buf)` Format a boolean value as string "1" or "0".
`static String`	`formatTimeDelta(long time, CharSequence sep)` Formats a time delta in human readable format.
`static StringBuilder`	`formatTo(StringBuilder a, double[] d, String sep)` Formats the double array d with the specified number format.
`static StringBuilder`	`formatTo(StringBuilder a, double[] d, String sep, NumberFormat nf)` Formats the double array d with the specified number format.
`static int`	`getConsoleWidth()` Get the width of the terminal window (on Unix xterms), with a default of 78 characters.
`static NumberFormat`	`makeNumberFormat(int digits)` Initialize a number format with ELKI standard options (US locale, no grouping).
`private static boolean`	`matchInf(byte[] str, byte firstchar, int start, int end)` Match "inf", "infinity" in a number of different capitalizations.
`private static boolean`	`matchInf(CharSequence str, char firstchar, int start, int end)` Match "inf", "infinity" in a number of different capitalizations.
`private static boolean`	`matchNaN(byte[] str, byte firstchar, int start, int end)` Match "NaN" in a number of different capitalizations.
`private static boolean`	`matchNaN(CharSequence str, char firstchar, int start, int end)` Match "NaN" in a number of different capitalizations.
`private static int`	`nextPosition(int a, int b)` Helper that is similar to `Math.min(a,b)`, except that negative values are considered "invalid".
`static String`	`pad(String o, int len)` Pad a string to a given length by adding whitespace to the right.
`static String`	`padRightAligned(String o, int len)` Pad a string to a given length by adding whitespace to the left.
`static double`	`parseDouble(byte[] str, int start, int end)` Parse a double from a character sequence.
`static double`	`parseDouble(CharSequence str)` Parse a double from a character sequence.
`static double`	`parseDouble(CharSequence str, int start, int end)` Parse a double from a character sequence.
`static long`	`parseLongBase10(CharSequence str, int start, int end)` Parse a long integer from a character sequence.
`static List<String>`	`splitAtLastBlank(String s, int width)` Splits the specified string at the last blank before width.
`static int`	`stringSize(int x)` Compute the number of characters needed to represent the integer x.
`static int`	`stringSize(long x)` Compute the number of characters needed to represent the integer x.
`static String`	`whitespace(int n)` Returns a string with the specified number of whitespace.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - NF
```
public static final NumberFormat NF
```
    Dynamic number formatter, but with language constraint.
  - NF0
```
public static final NumberFormat NF0
```
    Number Formatter (0 digits) for output purposes.
  - NF2
```
public static final NumberFormat NF2
```
    Number Formatter (2 digits) for output purposes.
  - NF3
```
public static final NumberFormat NF3
```
    Number Formatter (3 digits) for output purposes.
  - NF4
```
public static final NumberFormat NF4
```
    Number Formatter (4 digits) for output purposes.
  - NF6
```
public static final NumberFormat NF6
```
    Number Formatter (6 digits) for output purposes.
  - NF8
```
public static final NumberFormat NF8
```
    Number Formatter (8 digits) for output purposes.
  - WHITESPACE_BUFFER
```
private static final String WHITESPACE_BUFFER
```
    Whitespace. The string should cover the commonly used length.
    
    See Also:
    Constant Field Values
  - NEWLINE
```
public static final String NEWLINE
```
    The system newline setting.
  - NONBREAKING_SPACE
```
public static final String NONBREAKING_SPACE
```
    Non-breaking unicode space character.
    
    See Also:
    Constant Field Values
  - TIME_UNIT_SIZES
```
private static final long[] TIME_UNIT_SIZES
```
    The time unit sizes: ms, s, m, h, d; all in ms.
  - TIME_UNIT_NAMES
```
private static final String[] TIME_UNIT_NAMES
```
    The strings used in serialization
  - TIME_UNIT_DIGITS
```
private static final int[] TIME_UNIT_DIGITS
```
    The number of digits used for formatting
  - EMPTY_STRING
```
private static final NumberFormatException EMPTY_STRING
```
    Preallocated exceptions.
  - EXPONENT_OVERFLOW
```
private static final NumberFormatException EXPONENT_OVERFLOW
```
    Preallocated exceptions.
  - INVALID_EXPONENT
```
private static final NumberFormatException INVALID_EXPONENT
```
    Preallocated exceptions.
  - TRAILING_CHARACTERS
```
private static final NumberFormatException TRAILING_CHARACTERS
```
    Preallocated exceptions.
  - PRECISION_OVERFLOW
```
private static final NumberFormatException PRECISION_OVERFLOW
```
    Preallocated exceptions.
  - NOT_A_NUMBER
```
private static final NumberFormatException NOT_A_NUMBER
```
    Preallocated exceptions.
  - MAX_LONG_OVERFLOW
```
private static final long MAX_LONG_OVERFLOW
```
    Maximum long that we can process without overflowing.
    
    See Also:
    Constant Field Values
  - MAX_INT_OVERFLOW
```
private static final int MAX_INT_OVERFLOW
```
    Maximum integer that we can process without overflowing.
    
    See Also:
    Constant Field Values
  - INFINITY_PATTERN
```
private static final char[] INFINITY_PATTERN
```
    Infinity pattern, with any capitalization
  - INFINITY_LENGTH
```
private static final int INFINITY_LENGTH
```
    Length of pattern
  - ZEROPADDING
```
private static final char[] ZEROPADDING
```
    Buffer for zero padding.
  - SPACEPADDING
```
private static final char[] SPACEPADDING
```
    Buffer for whitespace padding.
- Constructor Detail
  - FormatUtil
```
public FormatUtil()
```
- Method Detail
  - makeNumberFormat
```
public static NumberFormat makeNumberFormat(int digits)
```
    Initialize a number format with ELKI standard options (US locale, no grouping).
    
    Parameters:
    digits - Number of digits to use
    
    Returns:
    Number format
  - format
```
public static String format(double[] d,
            String sep)
```
    Formats the double array d with the specified separator.
    
    Parameters:
    d - the double array to be formatted
    sep - the separator between the single values of the double array, e.g. ','
    
    Returns:
    a String representing the double array d
  - format
```
public static String format(double[] d,
            NumberFormat nf)
```
    Formats the double array d with the specified number format.
    
    Parameters:
    d - the double array to be formatted
    nf - the number format to be used for formatting
    
    Returns:
    a String representing the double array d
  - format
```
public static String format(double[] d,
            String sep,
            NumberFormat nf)
```
    Formats the double array d with the specified number format.
    
    Parameters:
    d - the double array to be formatted
    sep - the separator between the single values of the double array, e.g. ','
    nf - the number format to be used for formatting
    
    Returns:
    a String representing the double array d
  - formatTo
```
public static StringBuilder formatTo(StringBuilder a,
                     double[] d,
                     String sep)
```
    Formats the double array d with the specified number format.
    
    Parameters:
    d - the double array to be formatted
    sep - the separator between the single values of the double array, e.g. ','
    
    Returns:
    a String representing the double array d
  - formatTo
```
public static StringBuilder formatTo(StringBuilder a,
                     double[] d,
                     String sep,
                     NumberFormat nf)
```
    Formats the double array d with the specified number format.
    
    Parameters:
    d - the double array to be formatted
    sep - the separator between the single values of the double array, e.g. ','
    nf - the number format to be used for formatting
    
    Returns:
    a String representing the double array d
  - format
```
public static String format(double[] d)
```
    Formats the double array d with ', ' as separator and 2 fraction digits.
    
    Parameters:
    d - the double array to be formatted
    
    Returns:
    a String representing the double array d
  - format
```
public static String format(double[][] d)
```
    Formats the double array d with ',' as separator and 2 fraction digits.
    
    Parameters:
    d - the double array to be formatted
    
    Returns:
    a String representing the double array d
  - format
```
public static String format(double[][] d,
            String sep1,
            String sep2,
            NumberFormat nf)
```
    Formats the array of double arrays d with 'the specified separators and fraction digits.
    
    Parameters:
    d - the double array to be formatted
    sep1 - the first separator of the outer array
    sep2 - the second separator of the inner array
    nf - the number format to use
    
    Returns:
    a String representing the double array d
  - format
```
public static String format(float[] d,
            String sep,
            NumberFormat nf)
```
    Formats the double array d with the specified number format.
    
    Parameters:
    d - the double array to be formatted
    sep - the separator between the single values of the double array, e.g. ','
    nf - the number format to be used for formatting
    
    Returns:
    a String representing the double array d
  - format
```
public static String format(float[] f)
```
    Formats the float array f with ',' as separator and 2 fraction digits.
    
    Parameters:
    f - the float array to be formatted
    
    Returns:
    a String representing the float array f
  - format
```
public static String format(int[] a,
            String sep)
```
    Formats the int array a for printing purposes.
    
    Parameters:
    a - the int array to be formatted
    sep - the separator between the single values of the float array, e.g. ','
    
    Returns:
    a String representing the int array a
  - format
```
public static String format(int[] a)
```
    Formats the int array a for printing purposes.
    
    Parameters:
    a - the int array to be formatted
    
    Returns:
    a String representing the int array a
  - format
```
public static String format(long[] a)
```
    Formats the long array a for printing purposes.
    
    Parameters:
    a - the long array to be formatted
    
    Returns:
    a String representing the long array a
  - format
```
public static String format(byte[] a)
```
    Formats the byte array a for printing purposes.
    
    Parameters:
    a - the byte array to be formatted
    
    Returns:
    a String representing the byte array a
  - format
```
public static String format(boolean[] b,
            String sep)
```
    Formats the boolean array b with ',' as separator.
    
    Parameters:
    b - the boolean array to be formatted
    sep - the separator between the single values of the double array, e.g. ','
    
    Returns:
    a String representing the boolean array b
  - format
```
public static String format(boolean b)
```
    Formats the boolean b.
    
    Parameters:
    b - the boolean to be formatted
    
    Returns:
    a String representing of the boolean b
  - format
```
public static String format(long[] bitSet,
            int dim,
            String sep)
```
    Returns a string representation of the specified bit set.
    
    Parameters:
    bitSet - the bitSet
    dim - the overall dimensionality of the bit set
    sep - the separator
    
    Returns:
    a string representation of the specified bit set.
  - format
```
public static String format(int dim,
            long[] bitSet)
```
    Returns a string representation of the specified bit set.
    
    Parameters:
    dim - the overall dimensionality of the bit set
    bitSet - the bitSet
    
    Returns:
    a string representation of the specified bit set.
  - format
```
public static String format(Collection<String> d,
            String sep)
```
    Formats the String collection with the specified separator.
    
    Parameters:
    d - the String collection to format
    sep - the separator between the single values of the double array, e.g. ' '
    
    Returns:
    a String representing the String Collection d
  - format
```
public static String format(Matrix m,
            int w,
            int d)
```
    Returns a string representation of this matrix.
    
    Parameters:
    w - column width
    d - number of digits after the decimal
    
    Returns:
    a string representation of this matrix
  - format
```
public static String format(Vector v,
            int w,
            int d)
```
    Returns a string representation of this matrix.
    
    Parameters:
    w - column width
    d - number of digits after the decimal
    
    Returns:
    a string representation of this matrix
  - format
```
public static String format(Matrix m,
            String pre)
```
    Returns a string representation of this matrix. In each line the specified String pre is prefixed.
    
    Parameters:
    pre - the prefix of each line
    
    Returns:
    a string representation of this matrix
  - format
```
public static String format(Matrix m,
            NumberFormat nf)
```
    returns String-representation of Matrix.
    
    Parameters:
    nf - NumberFormat to specify output precision
    
    Returns:
    String representation of this Matrix in precision as specified by given NumberFormat
  - format
```
public static String format(Matrix m)
```
    returns String-representation of Matrix.
    
    Returns:
    String representation of this Matrix
  - format
```
public static String format(Vector m,
            NumberFormat nf)
```
    returns String-representation of Vector.
    
    Parameters:
    nf - NumberFormat to specify output precision
    
    Returns:
    String representation of this Matrix in precision as specified by given NumberFormat
  - format
```
public static String format(Vector m)
```
    Returns String-representation of Vector.
    
    Returns:
    String representation of this Vector
  - format
```
public static String format(Vector v,
            String pre)
```
    Returns a string representation of this matrix. In each line the specified String pre is prefixed.
    
    Parameters:
    pre - the prefix of each line
    
    Returns:
    a string representation of this matrix
  - format
```
public static String format(Matrix m,
            String pre,
            NumberFormat nf)
```
    Returns a string representation of this matrix. In each line the specified String pre<\code> is prefixed.
    Parameters: nf - number format for output accuracy pre - the prefix of each line Returns: a string representation of this matrix
  findSplitpoint public static int findSplitpoint(String s, int width) Find the first space before position w or if there is none after w. Parameters: s - String width - Width Returns: index of best whitespace or -1 if no whitespace was found. nextPosition private static int nextPosition(int a, int b) Helper that is similar to Math.min(a,b), except that negative values are considered "invalid". Parameters: a - String position b - String position Returns: Math.min(a,b) if a >= 0 and b >= 0, otherwise whichever is positive. splitAtLastBlank public static List<String> splitAtLastBlank(String s, int width) Splits the specified string at the last blank before width. If there is no blank before the given width, it is split at the next. Parameters: s - the string to be split width - int Returns: string fragments whitespace public static String whitespace(int n) Returns a string with the specified number of whitespace. Parameters: n - the number of whitespace characters Returns: a string with the specified number of blanks pad public static String pad(String o, int len) Pad a string to a given length by adding whitespace to the right. Parameters: o - original string len - destination length Returns: padded string of at least length len (and o otherwise) padRightAligned public static String padRightAligned(String o, int len) Pad a string to a given length by adding whitespace to the left. Parameters: o - original string len - destination length Returns: padded string of at least length len (and o otherwise) getConsoleWidth public static int getConsoleWidth() Get the width of the terminal window (on Unix xterms), with a default of 78 characters. Returns: Terminal width formatTimeDelta public static String formatTimeDelta(long time, CharSequence sep) Formats a time delta in human readable format. Parameters: time - time delta in ms Returns: Formatted string format public static String format(String[] d, String sep) Formats the string array d with the specified separator. Parameters: d - the string array to be formatted sep - the separator between the single values of the double array, e.g. ',' Returns: a String representing the string array d parseDouble public static double parseDouble(CharSequence str) Parse a double from a character sequence. In contrast to Javas Double.parseDouble(java.lang.String), this will not create an object and thus is expected to put less load on the garbage collector. It will accept some more spellings of NaN and infinity, thus removing the need for checking for these independently. Parameters: str - String Returns: Double value parseDouble public static double parseDouble(CharSequence str, int start, int end) Parse a double from a character sequence. In contrast to Javas Double.parseDouble(java.lang.String), this will not create an object and thus is expected to put less load on the garbage collector. It will accept some more spellings of NaN and infinity, thus removing the need for checking for these independently. Parameters: str - String start - Begin end - End Returns: Double value parseDouble public static double parseDouble(byte[] str, int start, int end) Parse a double from a character sequence. In contrast to Javas Double.parseDouble(java.lang.String), this will not create an object and thus is expected to put less load on the garbage collector. It will accept some more spellings of NaN and infinity, thus removing the need for checking for these independently. Parameters: str - String start - Begin end - End Returns: Double value matchNaN private static boolean matchNaN(CharSequence str, char firstchar, int start, int end) Match "NaN" in a number of different capitalizations. Parameters: str - String to match firstchar - First character start - Interval begin end - Interval end Returns: true when NaN was recognized. matchNaN private static boolean matchNaN(byte[] str, byte firstchar, int start, int end) Match "NaN" in a number of different capitalizations. Parameters: str - String to match firstchar - First character start - Interval begin end - Interval end Returns: true when NaN was recognized. matchInf private static boolean matchInf(CharSequence str, char firstchar, int start, int end) Match "inf", "infinity" in a number of different capitalizations. Parameters: str - String to match firstchar - First character start - Interval begin end - Interval end Returns: true when infinity was recognized. matchInf private static boolean matchInf(byte[] str, byte firstchar, int start, int end) Match "inf", "infinity" in a number of different capitalizations. Parameters: str - String to match firstchar - First character start - Interval begin end - Interval end Returns: true when infinity was recognized. parseLongBase10 public static long parseLongBase10(CharSequence str, int start, int end) Parse a long integer from a character sequence. Parameters: str - String start - Begin end - End Returns: Double value format public static StringBuilder format(boolean b, StringBuilder buf) Format a boolean value as string "true" or "false". Parameters: b - Boolean to Format buf - Buffer to append to Returns: Same buffer formatBit public static StringBuilder formatBit(boolean b, StringBuilder buf) Format a boolean value as string "1" or "0". Parameters: b - Boolean to Format buf - Buffer to append to Returns: Same buffer format public static StringBuilder format(int i, StringBuilder buf) Format an integer value as decimal. Parameters: i - Integer value to format. buf - Buffer to append to Returns: Same buffer format public static StringBuilder format(long i, StringBuilder buf) Format a long value as decimal. Parameters: i - Long value to format. buf - Buffer to append to Returns: Same buffer appendZeros public static StringBuilder appendZeros(StringBuilder buf, int zeros) Append zeros to a buffer. Parameters: buf - Buffer to append to zeros - Number of zeros to append. Returns: Buffer appendSpace public static StringBuilder appendSpace(StringBuilder buf, int spaces) Append whitespace to a buffer. Parameters: buf - Buffer to append to spaces - Number of spaces to append. Returns: Buffer stringSize public static int stringSize(int x) Compute the number of characters needed to represent the integer x. Reimplementation of Long.stringSize(long), but public and without loop. Parameters: x - Integer value Returns: Number of digits needed stringSize public static int stringSize(long x) Compute the number of characters needed to represent the integer x. Reimplementation of Long.stringSize(long), but public and without loop. Parameters: x - Integer value Returns: Number of digits needed

Class FormatUtil

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

NF

NF0

NF2

NF3

NF4

NF6

NF8

WHITESPACE_BUFFER

NEWLINE

NONBREAKING_SPACE

TIME_UNIT_SIZES

TIME_UNIT_NAMES

TIME_UNIT_DIGITS

EMPTY_STRING

EXPONENT_OVERFLOW

INVALID_EXPONENT

TRAILING_CHARACTERS

PRECISION_OVERFLOW

NOT_A_NUMBER

MAX_LONG_OVERFLOW

MAX_INT_OVERFLOW

INFINITY_PATTERN

INFINITY_LENGTH

ZEROPADDING

SPACEPADDING

Constructor Detail

FormatUtil

Method Detail

makeNumberFormat

format

format

format

formatTo

formatTo

format

format

format

format

format

format

format

format

format

format

format

format

format

format

format

format

format

format

format

format

format

format

format

findSplitpoint

nextPosition

splitAtLastBlank

whitespace

pad

padRightAligned

getConsoleWidth

formatTimeDelta

format

parseDouble

parseDouble

parseDouble

matchNaN

matchNaN

matchInf

matchInf

parseLongBase10