Filter

Block Group:	Table Operations
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The Filter block returns a new table that contains only the rows from the input table that meet a condition.

For information on using dataflow blocks, see Dataflow.

For answers to some common questions about working with tables, see Tables.

The following properties of the Filter block can take input and give output.

• input (table)
• condition (string)

input receives the table that you want to filter.

condition specifies the condition of the filter. Use JavaScript notation.

The following properties of the Filter block can give output but cannot take input.

• print (string)
• output (table)

print returns output from the condition field. Use it for debugging.

output returns the filtered table.

These examples of values for the condition property use the following table:

row,value
0,string
1,STRING
2,StRiNg

Using the table above, the following numeric expressions are example values for the condition property:

• row == 0 causes row 0 to be returned.
• row > 0 causes rows 1 and 2 to be returned.
• row > -1 causes all rows to be returned.

Using the table above, the following string expressions are example values for the condition property:

• String(value) == "string" causes row 0 to be returned.
• String(value).indexOf("S") > -1 causes rows 1 and 2 to be returned, because a capital S is included in the string in those rows.
• String(value).toLowerCase().indexOf("string") > -1 returns all rows, because the strings are converted to lowercase before being tested.

The following example limits a table to include only rows for which the timestamp is on June 14th or June 15th, 2016.

$thisRow['timestamp'] > '2016-06-14' && $thisRow['timestamp'] <= '2016-06-15T23:59:59'

You can use $.<variable> in Column Mapping and Filter to store any temporary variable between rows.

The following condition returns a table that contains rows from the input table only if the v1 value in this row matches the v1 value in the previous row.

v1==function(){var prev = $.v1cache; $.v1cache = v1; return prev}()

The following image shows an example of the Filter block. In this example, the table is filtered to contain only rows where the Fan_Status column holds the string OFF.