Produces the value histogram of a Geo Time Series™ or (since 2.2.0) of a GTS Encoder.
The histogram is a map with an entry for each value (used as the map key), with an associated value equal to the number of occurrences of the value in the series.
If the input is a bucketized Geo Time Series™, the
NULL key will have an associated value which is the number of buckets without values (assuming no datapoints were added at timestamps other than those of buckets).
When the input is a GTS Encoder, keys may be BigDecimal, LONG, DOUBLE, BOOLEAN or STRING, binary values are not used as keys, their STRING representation (in ISO-8859-1) is used.