Package io.deephaven.engine.util

Class TableTools

java.lang.Object

io.deephaven.engine.util.TableTools

public class TableTools
extends Object

Tools for working with tables. This includes methods to examine tables, combine them, convert them to and from CSV files, and create and manipulate columns.

Field Summary

Fields

Modifier and Type	Field	Description
static final String	NULL_STRING

Constructor Summary

Constructors

Constructor	Description
TableTools()

Method Summary

Modifier and Type	Method	Description
static String	base64Fingerprint(Table source)	Compute the SHA256 hash of the input table and return it in base64 string format.
static ColumnHolder<Boolean>	booleanCol(String name, Boolean... data)	Returns a ColumnHolder of type Boolean that can be used when creating in-memory tables.
static ColumnHolder<Byte>	byteCol(String name, byte... data)	Returns a ColumnHolder of type byte that can be used when creating in-memory tables.
static ColumnHolder<Character>	charCol(String name, char... data)	Returns a ColumnHolder of type char that can be used when creating in-memory tables.
static <T> ColumnHolder<T>	col(String name, T... data)	Returns a ColumnHolder that can be used when creating in-memory tables.
static ColumnSource<Byte>	colSource(byte... values)	Creates an in-memory column of type byte for a collection of values.
static ColumnSource<Character>	colSource(char... values)	Creates an in-memory column of type char for a collection of values.
static ColumnSource<Double>	colSource(double... values)	Creates an in-memory column of type double for a collection of values.
static ColumnSource<Float>	colSource(float... values)	Creates an in-memory column of type float for a collection of values.
static ColumnSource<Integer>	colSource(int... values)	Creates an in-memory column of type int for a collection of values.
static ColumnSource<Long>	colSource(long... values)	Creates an in-memory column of type long for a collection of values.
static ColumnSource<Short>	colSource(short... values)	Creates an in-memory column of type short for a collection of values.
static <T> ColumnSource<T>	colSource(Class<T> clazz, Collection<T> values)	Creates an in-memory column of the specified type for a collection of values.
static byte[]	computeFingerprint(Table source)	Compute the SHA256 hash of the input table.
static String	diff(Table actualResult, Table expectedResult, long maxDiffLines)	Computes the difference of two tables for use in verification.
static String	diff(Table actualResult, Table expectedResult, long maxDiffLines, EnumSet<TableDiff.DiffItems> itemsToSkip)	Computes the difference of two tables for use in verification.
static Pair<String,Long>	diffPair(Table actualResult, Table expectedResult, long maxDiffLines, EnumSet<TableDiff.DiffItems> itemsToSkip)	Computes the difference of two tables for use in verification.
static ColumnHolder<Double>	doubleCol(String name, double... data)	Returns a ColumnHolder of type double that can be used when creating in-memory tables.
static Table	emptyTable(long size)	Returns a new, empty Deephaven Table.
static ColumnHolder<Float>	floatCol(String name, float... data)	Returns a ColumnHolder of type float that can be used when creating in-memory tables.
static String	html(Table source)	Returns a printout of a table formatted as HTML.
static ColumnHolder<Instant>	instantCol(String name, Instant... data)	Returns a ColumnHolder of type Instant that can be used when creating in-memory tables.
static ColumnHolder<Integer>	intCol(String name, int... data)	Returns a ColumnHolder of type int that can be used when creating in-memory tables.
static ColumnHolder<Long>	longCol(String name, long... data)	Returns a ColumnHolder of type long that can be used when creating in-memory tables.
static Table	merge(Table... tables)	Concatenates multiple Deephaven Tables into a single Table.
static Table	merge(Collection<Table> tables)	Concatenates multiple Deephaven Tables into a single Table.
static Table	merge(List<Table> theList)	Concatenates multiple Deephaven Tables into a single Table.
static Table	mergeSorted(String keyColumn, Table... tables)	Concatenates multiple sorted Deephaven Tables into a single Table sorted by the specified key column.
static Table	mergeSorted(String keyColumn, Collection<Table> tables)	Concatenates multiple sorted Deephaven Tables into a single Table sorted by the specified key column.
static Table	newTable(long size, List<String> names, List<ColumnSource<?>> columnSources)	Creates a new Table.
static Table	newTable(long size, Map<String,ColumnSource<?>> columns)	Creates a new Table.
static Table	newTable(ColumnHolder<?>... columnHolders)	Creates a new Table.
static Table	newTable(TableDefinition definition)	Creates a new Table.
static Table	newTable(TableDefinition definition, ColumnHolder<?>... columnHolders)
static String	nullToNullString(Object obj)
static String	nullTypeAsString(Class<?> dataType)
static <T> ColumnSource<T>	objColSource(T... values)	Creates an in-memory column of the specified type for a collection of values
static Table	roundDecimalColumns(Table table)	Produce a new table with all the columns of this table, in the same order, but with double and float columns rounded to longs.
static Table	roundDecimalColumns(Table table, String... columns)	Produce a new table with all the columns of this table, in the same order, but with double and float columns rounded to longs.
static Table	roundDecimalColumnsExcept(Table table, String... columnsNotToRound)	Produce a new table with all the columns of this table, in the same order, but with all double and float columns rounded to longs, except for the specified columnsNotToRound.
static ColumnHolder<Short>	shortCol(String name, short... data)	Returns a ColumnHolder of type short that can be used when creating in-memory tables.
static void	show(Table source, long maxRowCount, String... columns)	Prints the first few rows of a table to standard output.
static void	show(Table source, long maxRowCount, ZoneId timeZone, PrintStream out, String... columns)	Prints the first few rows of a table to standard output.
static void	show(Table source, long maxRowCount, ZoneId timeZone, String... columns)	Prints the first few rows of a table to standard output.
static void	show(Table source, long maxRowCount, ZoneId timeZone, String delimiter, PrintStream out, boolean showRowSet, String... columns)	Prints the first few rows of a table to standard output.
static void	show(Table source, String... columns)	Prints the first few rows of a table to standard output.
static void	show(Table source, ZoneId timeZone, String... columns)	Prints the first few rows of a table to standard output.
static void	showCommaDelimited(Table source, long maxRowCount, String... columns)	Prints the first few rows of a table to standard output, with commas between values.
static void	showCommaDelimited(Table source, String... columns)	Prints the first few rows of a table to standard output, with commas between values.
static void	showWithRowSet(Table source, long firstRow, long lastRow, PrintStream out, String... columns)	Prints the first few rows of a table to standard output, and also prints the details of the row keys and row positions that provided the values.
static void	showWithRowSet(Table source, long firstRow, long lastRow, String... columns)	Prints the first few rows of a table to standard output, and also prints the details of the row keys and row positions that provided the values.
static void	showWithRowSet(Table source, long maxRowCount, String... columns)	Prints the first few rows of a table to standard output, and also prints the details of the row keys and row positions that provided the values.
static void	showWithRowSet(Table source, long maxRowCount, ZoneId timeZone, PrintStream out, String... columns)	Prints the first few rows of a table to standard output, and also prints the details of the row keys and row positions that provided the values.
static void	showWithRowSet(Table source, String... columns)	Prints the first few rows of a table to standard output, and also prints the details of the row keys and row positions that provided the values.
static String	string(@NotNull Table table, int size, ZoneId timeZone, @NotNull String... columns)	Returns the first few rows of a table as a pipe-delimited string.
static String	string(Table t, int size, String... columns)	Returns the first few rows of a table as a pipe-delimited string.
static String	string(Table t, String... columns)	Returns the first few rows of a table as a pipe-delimited string.
static String	string(Table t, ZoneId timeZone, String... columns)	Returns the first few rows of a table as a pipe-delimited string.
static ColumnHolder<String>	stringCol(String name, String... data)	Returns a ColumnHolder of type String that can be used when creating in-memory tables.
static Table	timeTable(long periodNanos)	Creates a table that adds a new row on a regular interval.
static Table	timeTable(long periodNanos, ReplayerInterface replayer)	Creates a table that adds a new row on a regular interval.
static Table	timeTable(Clock clock, Instant startTime, long periodNanos)	Creates a table that adds a new row on a regular interval.
static Table	timeTable(String period)	Creates a table that adds a new row on a regular interval.
static Table	timeTable(String startTime, long periodNanos)	Creates a table that adds a new row on a regular interval.
static Table	timeTable(String startTime, long periodNanos, ReplayerInterface replayer)	Creates a table that adds a new row on a regular interval.
static Table	timeTable(String period, ReplayerInterface replayer)	Creates a table that adds a new row on a regular interval.
static Table	timeTable(String startTime, String period)	Creates a table that adds a new row on a regular interval.
static Table	timeTable(String startTime, String period, ReplayerInterface replayer)	Creates a table that adds a new row on a regular interval.
static Table	timeTable(Instant startTime, long periodNanos)	Creates a table that adds a new row on a regular interval.
static Table	timeTable(Instant startTime, long periodNanos, ReplayerInterface replayer)	Creates a table that adds a new row on a regular interval.
static Table	timeTable(Instant startTime, String period)	Creates a table that adds a new row on a regular interval.
static Table	timeTable(Instant startTime, String period, ReplayerInterface replayer)	Creates a table that adds a new row on a regular interval.
static TimeTable.Builder	timeTableBuilder()	Creates a new time table builder.
static Class<?>	typeFromName(String dataTypeStr)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

NULL_STRING

public static final String NULL_STRING

See Also:

• Constant Field Values

Constructor Details

TableTools

public TableTools()

Method Details

show

public static void show(Table source,
 String... columns)

Prints the first few rows of a table to standard output.

Parameters:

source - a Deephaven table object

columns - varargs of column names to display

showWithRowSet

public static void showWithRowSet(Table source,
 String... columns)

Prints the first few rows of a table to standard output, and also prints the details of the row keys and row positions that provided the values.

Parameters:

source - a Deephaven table object

columns - varargs of column names to display

showCommaDelimited

public static void showCommaDelimited(Table source,
 String... columns)

Prints the first few rows of a table to standard output, with commas between values.

Parameters:

source - a Deephaven table object

columns - varargs of column names to display

show

public static void show(Table source,
 ZoneId timeZone,
 String... columns)

Prints the first few rows of a table to standard output.

Parameters:

source - a Deephaven table object

timeZone - a time zone constant relative to which date time data should be adjusted

columns - varargs of column names to display

show

public static void show(Table source,
 long maxRowCount,
 String... columns)

Prints the first few rows of a table to standard output.

Parameters:

source - a Deephaven table object

maxRowCount - the number of rows to return

columns - varargs of column names to display

showWithRowSet

public static void showWithRowSet(Table source,
 long maxRowCount,
 String... columns)

Prints the first few rows of a table to standard output, and also prints the details of the row keys and row positions that provided the values.

Parameters:

source - a Deephaven table object

maxRowCount - the number of rows to return

columns - varargs of column names to display

showCommaDelimited

public static void showCommaDelimited(Table source,
 long maxRowCount,
 String... columns)

Prints the first few rows of a table to standard output, with commas between values.

Parameters:

source - a Deephaven table object

maxRowCount - the number of rows to return

columns - varargs of column names to display

show

public static void show(Table source,
 long maxRowCount,
 ZoneId timeZone,
 String... columns)

Prints the first few rows of a table to standard output.

Parameters:

source - a Deephaven table object

maxRowCount - the number of rows to return

timeZone - a time zone constant relative to which date time data should be adjusted

columns - varargs of column names to display

show

public static void show(Table source,
 long maxRowCount,
 ZoneId timeZone,
 PrintStream out,
 String... columns)

Prints the first few rows of a table to standard output.

Parameters:

source - a Deephaven table object

maxRowCount - the number of rows to return

timeZone - a time zone constant relative to which date time data should be adjusted

out - a PrintStream destination to which to print the data

columns - varargs of column names to display

showWithRowSet

public static void showWithRowSet(Table source,
 long maxRowCount,
 ZoneId timeZone,
 PrintStream out,
 String... columns)

Prints the first few rows of a table to standard output, and also prints the details of the row keys and row positions that provided the values.

Parameters:

source - a Deephaven table object

maxRowCount - the number of rows to return

timeZone - a time zone constant relative to which date time data should be adjusted

out - a PrintStream destination to which to print the data

columns - varargs of column names to display

showWithRowSet

public static void showWithRowSet(Table source,
 long firstRow,
 long lastRow,
 PrintStream out,
 String... columns)

Prints the first few rows of a table to standard output, and also prints the details of the row keys and row positions that provided the values.

Parameters:

source - a Deephaven table object

firstRow - the firstRow to display

lastRow - the lastRow (exclusive) to display

out - a PrintStream destination to which to print the data

columns - varargs of column names to display

show

public static void show(Table source,
 long maxRowCount,
 ZoneId timeZone,
 String delimiter,
 PrintStream out,
 boolean showRowSet,
 String... columns)

Prints the first few rows of a table to standard output.

Parameters:

source - a Deephaven table object

maxRowCount - the number of rows to return

timeZone - a time zone constant relative to which date time data should be adjusted

delimiter - a String value to use between printed values

out - a PrintStream destination to which to print the data

showRowSet - a boolean indicating whether to also print rowSet details

columns - varargs of column names to display

showWithRowSet

public static void showWithRowSet(Table source,
 long firstRow,
 long lastRow,
 String... columns)

Prints the first few rows of a table to standard output, and also prints the details of the row keys and row positions that provided the values.

Parameters:

source - a Deephaven table object

firstRow - the firstRow to display

lastRow - the lastRow (exclusive) to display

columns - varargs of column names to display

string

public static String string(Table t,
 String... columns)

Returns the first few rows of a table as a pipe-delimited string.

Parameters:

t - a Deephaven table object

columns - varargs of columns to include in the result

Returns:

a String

string

public static String string(Table t,
 int size,
 String... columns)

Returns the first few rows of a table as a pipe-delimited string.

Parameters:

t - a Deephaven table object

size - the number of rows to return

columns - varargs of columns to include in the result

Returns:

a String

string

public static String string(Table t,
 ZoneId timeZone,
 String... columns)

Returns the first few rows of a table as a pipe-delimited string.

Parameters:

t - a Deephaven table object

timeZone - a time zone constant relative to which date time data should be adjusted

columns - varargs of columns to include in the result

Returns:

a String

string

public static String string(@NotNull
 @NotNull Table table,
 int size,
 ZoneId timeZone,
 @NotNull
 @NotNull String... columns)

Returns the first few rows of a table as a pipe-delimited string.

Parameters:

table - a Deephaven table object

size - the number of rows to return

timeZone - a time zone constant relative to which date time data should be adjusted

columns - varargs of columns to include in the result

Returns:

a String

html

public static String html(Table source)

Returns a printout of a table formatted as HTML. Limit use to small tables to avoid running out of memory.

Parameters:

source - a Deephaven table object

Returns:

a String of the table printout formatted as HTML

diff

public static String diff(Table actualResult,
 Table expectedResult,
 long maxDiffLines)

Computes the difference of two tables for use in verification.

Parameters:

actualResult - first Deephaven table object to compare

expectedResult - second Deephaven table object to compare

maxDiffLines - stop comparing after this many differences are found

Returns:

String report of the detected differences

diff

public static String diff(Table actualResult,
 Table expectedResult,
 long maxDiffLines,
 EnumSet<TableDiff.DiffItems> itemsToSkip)

Computes the difference of two tables for use in verification.

Parameters:

actualResult - first Deephaven table object to compare

expectedResult - second Deephaven table object to compare

maxDiffLines - stop comparing after this many differences are found

itemsToSkip - EnumSet of checks not to perform, such as checking column order, or exact match of double values

Returns:

String report of the detected differences

diffPair

public static Pair<String,Long> diffPair(Table actualResult,
 Table expectedResult,
 long maxDiffLines,
 EnumSet<TableDiff.DiffItems> itemsToSkip)

Computes the difference of two tables for use in verification.

Parameters:

actualResult - first Deephaven table object to compare

expectedResult - second Deephaven table object to compare

maxDiffLines - stop comparing after this many differences are found

itemsToSkip - EnumSet of checks not to perform, such as checking column order, or exact match of double values

Returns:

a pair of String report of the detected differences, and the first different row (0 if there are no different data values)

nullToNullString

public static String nullToNullString(Object obj)

colSource

public static <T> ColumnSource<T> colSource(Class<T> clazz,
 Collection<T> values)

Creates an in-memory column of the specified type for a collection of values.

Type Parameters:

T - the type to use for the new column

Parameters:

clazz - the class to use for the new column

values - a collection of values to populate the new column

Returns:

a Deephaven ColumnSource object

objColSource

public static <T> ColumnSource<T> objColSource(T... values)

Creates an in-memory column of the specified type for a collection of values

Type Parameters:

T - the type to use for the new column

Parameters:

values - a collection of values to populate the new column

Returns:

a Deephaven ColumnSource object

colSource

public static ColumnSource<Long> colSource(long... values)

Creates an in-memory column of type long for a collection of values.

Parameters:

values - a collection of values to populate the new column

Returns:

a Deephaven ColumnSource object

colSource

public static ColumnSource<Integer> colSource(int... values)

Creates an in-memory column of type int for a collection of values.

Parameters:

values - a collection of values to populate the new column

Returns:

a Deephaven ColumnSource object

colSource

public static ColumnSource<Short> colSource(short... values)

Creates an in-memory column of type short for a collection of values.

Parameters:

values - a collection of values to populate the new column

Returns:

a Deephaven ColumnSource object

colSource

public static ColumnSource<Byte> colSource(byte... values)

Creates an in-memory column of type byte for a collection of values.

Parameters:

values - a collection of values to populate the new column

Returns:

a Deephaven ColumnSource object

colSource

public static ColumnSource<Character> colSource(char... values)

Creates an in-memory column of type char for a collection of values.

Parameters:

values - a collection of values to populate the new column

Returns:

a Deephaven ColumnSource object

colSource

public static ColumnSource<Double> colSource(double... values)

Creates an in-memory column of type double for a collection of values.

Parameters:

values - a collection of values to populate the new column

Returns:

a Deephaven ColumnSource object

colSource

public static ColumnSource<Float> colSource(float... values)

Creates an in-memory column of type float for a collection of values.

Parameters:

values - a collection of values to populate the new column

Returns:

a Deephaven ColumnSource object

col

public static <T> ColumnHolder<T> col(String name,
 T... data)

Returns a ColumnHolder that can be used when creating in-memory tables.

Type Parameters:

T - the type of the column

Parameters:

name - name of the column

data - a list of values for the column

Returns:

a Deephaven ColumnHolder object

stringCol

public static ColumnHolder<String> stringCol(String name,
 String... data)

Returns a ColumnHolder of type String that can be used when creating in-memory tables.

Parameters:

name - name of the column

data - a list of values for the column

Returns:

a Deephaven ColumnHolder object

instantCol

public static ColumnHolder<Instant> instantCol(String name,
 Instant... data)

Returns a ColumnHolder of type Instant that can be used when creating in-memory tables.

Parameters:

name - name of the column

data - a list of values for the column

Returns:

a Deephaven ColumnHolder object

booleanCol

public static ColumnHolder<Boolean> booleanCol(String name,
 Boolean... data)

Returns a ColumnHolder of type Boolean that can be used when creating in-memory tables.

Parameters:

name - name of the column

data - a list of values for the column

Returns:

a Deephaven ColumnHolder object

longCol

public static ColumnHolder<Long> longCol(String name,
 long... data)

Returns a ColumnHolder of type long that can be used when creating in-memory tables.

Parameters:

name - name of the column

data - a list of values for the column

Returns:

a Deephaven ColumnHolder object

intCol

public static ColumnHolder<Integer> intCol(String name,
 int... data)

Returns a ColumnHolder of type int that can be used when creating in-memory tables.

Parameters:

name - name of the column

data - a list of values for the column

Returns:

a Deephaven ColumnHolder object

shortCol

public static ColumnHolder<Short> shortCol(String name,
 short... data)

Returns a ColumnHolder of type short that can be used when creating in-memory tables.

Parameters:

name - name of the column

data - a list of values for the column

Returns:

a Deephaven ColumnHolder object

byteCol

public static ColumnHolder<Byte> byteCol(String name,
 byte... data)

Returns a ColumnHolder of type byte that can be used when creating in-memory tables.

Parameters:

name - name of the column

data - a list of values for the column

Returns:

a Deephaven ColumnHolder object

charCol

public static ColumnHolder<Character> charCol(String name,
 char... data)

Returns a ColumnHolder of type char that can be used when creating in-memory tables.

Parameters:

name - name of the column

data - a list of values for the column

Returns:

a Deephaven ColumnHolder object

doubleCol

public static ColumnHolder<Double> doubleCol(String name,
 double... data)

Returns a ColumnHolder of type double that can be used when creating in-memory tables.

Parameters:

name - name of the column

data - a list of values for the column

Returns:

a Deephaven ColumnHolder object

floatCol

public static ColumnHolder<Float> floatCol(String name,
 float... data)

Returns a ColumnHolder of type float that can be used when creating in-memory tables.

Parameters:

name - name of the column

data - a list of values for the column

Returns:

a Deephaven ColumnHolder object

emptyTable

public static Table emptyTable(long size)

Returns a new, empty Deephaven Table.

Parameters:

size - the number of rows to allocate space for

Returns:

a Deephaven Table with no columns.

newTable

public static Table newTable(long size,
 List<String> names,
 List<ColumnSource<?>> columnSources)

Creates a new Table.

Parameters:

size - the number of rows to allocate

names - a List of column names

columnSources - a List of the ColumnSource(s)

Returns:

a Deephaven Table

newTable

public static Table newTable(long size,
 Map<String,ColumnSource<?>> columns)

Creates a new Table.

Parameters:

size - the number of rows to allocate

columns - a Map of column names and ColumnSources

Returns:

a Deephaven Table

newTable

public static Table newTable(TableDefinition definition)

Creates a new Table.

Parameters:

definition - the TableDefinition (column names and properties) to use for the new table

Returns:

an empty Deephaven Table

newTable

public static Table newTable(ColumnHolder<?>... columnHolders)

Creates a new Table.

Parameters:

columnHolders - a list of ColumnHolders from which to create the table

Returns:

a Deephaven Table

newTable

public static Table newTable(TableDefinition definition,
 ColumnHolder<?>... columnHolders)

timeTable

public static Table timeTable(String period)

Creates a table that adds a new row on a regular interval.

Parameters:

period - time interval between new row additions.

Returns:

time table

timeTable

public static Table timeTable(String period,
 ReplayerInterface replayer)

Creates a table that adds a new row on a regular interval.

Parameters:

period - time interval between new row additions

replayer - data replayer

Returns:

time table

timeTable

public static Table timeTable(Instant startTime,
 String period)

Creates a table that adds a new row on a regular interval.

Parameters:

startTime - start time for adding new rows

period - time interval between new row additions

Returns:

time table

timeTable

public static Table timeTable(Instant startTime,
 String period,
 ReplayerInterface replayer)

Creates a table that adds a new row on a regular interval.

Parameters:

startTime - start time for adding new rows

period - time interval between new row additions

replayer - data replayer

Returns:

time table

timeTable

public static Table timeTable(String startTime,
 String period)

Creates a table that adds a new row on a regular interval.

Parameters:

startTime - start time for adding new rows

period - time interval between new row additions

Returns:

time table

timeTable

public static Table timeTable(String startTime,
 String period,
 ReplayerInterface replayer)

Creates a table that adds a new row on a regular interval.

Parameters:

startTime - start time for adding new rows

period - time interval between new row additions

replayer - data replayer

Returns:

time table

timeTable

public static Table timeTable(long periodNanos)

Creates a table that adds a new row on a regular interval.

Parameters:

periodNanos - time interval between new row additions in nanoseconds.

Returns:

time table

timeTable

public static Table timeTable(long periodNanos,
 ReplayerInterface replayer)

Creates a table that adds a new row on a regular interval.

Parameters:

periodNanos - time interval between new row additions in nanoseconds.

replayer - data replayer

Returns:

time table

timeTable

public static Table timeTable(Instant startTime,
 long periodNanos)

Creates a table that adds a new row on a regular interval.

Parameters:

startTime - start time for adding new rows

periodNanos - time interval between new row additions in nanoseconds.

Returns:

time table

timeTable

public static Table timeTable(Instant startTime,
 long periodNanos,
 ReplayerInterface replayer)

Creates a table that adds a new row on a regular interval.

Parameters:

startTime - start time for adding new rows

periodNanos - time interval between new row additions in nanoseconds.

replayer - data replayer

Returns:

time table

timeTable

public static Table timeTable(String startTime,
 long periodNanos)

Creates a table that adds a new row on a regular interval.

Parameters:

startTime - start time for adding new rows

periodNanos - time interval between new row additions in nanoseconds.

Returns:

time table

timeTable

public static Table timeTable(String startTime,
 long periodNanos,
 ReplayerInterface replayer)

Creates a table that adds a new row on a regular interval.

Parameters:

startTime - start time for adding new rows

periodNanos - time interval between new row additions in nanoseconds.

replayer - data replayer

Returns:

time table

timeTable

public static Table timeTable(Clock clock,
 Instant startTime,
 long periodNanos)

Creates a table that adds a new row on a regular interval.

Parameters:

clock - the clock

startTime - start time for adding new rows

periodNanos - time interval between new row additions in nanoseconds.

Returns:

time table

timeTableBuilder

public static TimeTable.Builder timeTableBuilder()

Creates a new time table builder.

Returns:

a time table builder

merge

public static Table merge(List<Table> theList)

Concatenates multiple Deephaven Tables into a single Table.

The resultant table will have rows from the same table together, in the order they are specified as inputs.

When ticking tables grow, they may run out of the 'pre-allocated' space for newly added rows. When more key- space is needed, tables in higher key-space are shifted to yet higher key-space to make room for new rows. Shifts are handled efficiently, but some downstream operations generate a linear O(n) amount of work per shifted row. When possible, one should favor ordering the constituent tables first by static/non-ticking sources followed by tables that are expected to grow at slower rates, and finally by tables that grow without bound.

Parameters:

theList - a List of Tables to be concatenated

Returns:

a Deephaven table object

merge

public static Table merge(Collection<Table> tables)

Concatenates multiple Deephaven Tables into a single Table.

The resultant table will have rows from the same table together, in the order they are specified as inputs.

When ticking tables grow, they may run out of the 'pre-allocated' space for newly added rows. When more key- space is needed, tables in higher key-space are shifted to yet higher key-space to make room for new rows. Shifts are handled efficiently, but some downstream operations generate a linear O(n) amount of work per shifted row. When possible, one should favor ordering the constituent tables first by static/non-ticking sources followed by tables that are expected to grow at slower rates, and finally by tables that grow without bound.

Parameters:

tables - a Collection of Tables to be concatenated

Returns:

a Deephaven table object

merge

public static Table merge(Table... tables)

Concatenates multiple Deephaven Tables into a single Table.

The resultant table will have rows from the same table together, in the order they are specified as inputs.

When ticking tables grow, they may run out of the 'pre-allocated' space for newly added rows. When more key- space is needed, tables in higher key-space are shifted to yet higher key-space to make room for new rows. Shifts are handled efficiently, but some downstream operations generate a linear O(n) amount of work per shifted row. When possible, one should favor ordering the constituent tables first by static/non-ticking sources followed by tables that are expected to grow at slower rates, and finally by tables that grow without bound.

Parameters:

tables - a list of Tables to be concatenated

Returns:

a Deephaven table object

mergeSorted

public static Table mergeSorted(String keyColumn,
 Table... tables)

Concatenates multiple sorted Deephaven Tables into a single Table sorted by the specified key column.

The input tables must each individually be sorted by keyColumn, otherwise results are undefined.

Parameters:

tables - sorted Tables to be concatenated

keyColumn - the column to use when sorting the concatenated results

Returns:

a Deephaven table object

mergeSorted

public static Table mergeSorted(String keyColumn,
 Collection<Table> tables)

Concatenates multiple sorted Deephaven Tables into a single Table sorted by the specified key column.

The input tables must each individually be sorted by keyColumn, otherwise results are undefined.

Parameters:

tables - a Collection of sorted Tables to be concatenated

keyColumn - the column to use when sorting the concatenated results

Returns:

a Deephaven table object

roundDecimalColumns

@ScriptApi
public static Table roundDecimalColumns(Table table)

Produce a new table with all the columns of this table, in the same order, but with double and float columns rounded to longs.

Returns:

The new Table, with all double and float columns rounded to longs.

roundDecimalColumnsExcept

@ScriptApi
public static Table roundDecimalColumnsExcept(Table table,
 String... columnsNotToRound)

Produce a new table with all the columns of this table, in the same order, but with all double and float columns rounded to longs, except for the specified columnsNotToRound.

Parameters:

columnsNotToRound - The names of the double and float columns not to round to longs

Returns:

The new Table, with columns modified as explained above

roundDecimalColumns

@ScriptApi
public static Table roundDecimalColumns(Table table,
 String... columns)

Produce a new table with all the columns of this table, in the same order, but with double and float columns rounded to longs.

Parameters:

columns - The names of the double and float columns to round.

Returns:

The new Table, with the specified columns rounded to longs.

Throws:

IllegalArgumentException - If columns is null, or if one of the specified columns is neither a double column nor a float column.

computeFingerprint

public static byte[] computeFingerprint(Table source)
                                 throws IOException

Compute the SHA256 hash of the input table.

The hash is computed using every value in each row, using toString for unrecognized objects. The hash also includes the input table definition column names and types.

Parameters:

source - The table to fingerprint

Returns:

The SHA256 hash of the table data and TableDefinition

Throws:

IOException - If an error occurs during the hashing.

base64Fingerprint

public static String base64Fingerprint(Table source)
                                throws IOException

Compute the SHA256 hash of the input table and return it in base64 string format.

Parameters:

source - The table to fingerprint

Returns:

The SHA256 hash of the table data and TableDefinition

Throws:

IOException - If an error occurs during the hashing.

nullTypeAsString

public static String nullTypeAsString(Class<?> dataType)

typeFromName

public static Class<?> typeFromName(String dataTypeStr)