SELECT v,  rolling_median_impute(v, 3) over() FROM (VALUES (1), (1.1), (0.9), (NULL), (0.95), (2.1), (1.95), (2.0), (2.05), (3.11), (2.99), (3.05), (3.0)) as t(v);
  v   | rolling_median_impute 
------+-----------------------
    1 |                     1
  1.1 |                   1.1
  0.9 |                   0.9
      |                  0.95
 0.95 |                  0.95
  2.1 |                   2.1
 1.95 |                  1.95
  2.0 |                     2
 2.05 |                  2.05
 3.11 |                  3.11
 2.99 |                  2.99
 3.05 |                  3.05
  3.0 |                     3
(13 rows)

SELECT v,  rolling_median_impute(v::double precision, 3) over() FROM (VALUES (NULL)) as t(v);
ERROR:  window size greater than number of values
DETAIL:  window size 3 is greater than total number of elements in partition: 1
HINT:  reduce window size
SELECT v,  rolling_median_impute(v, 3) over() FROM (VALUES (1), (1.1), (NULL), (NULL)) as t(v);
ERROR:  Too few non-nulls
DETAIL:  window size 3 is greater than total number of non-null elements in partition: 2
HINT:  reduce window size
SELECT v,  rolling_median_impute(v, 3) over() FROM (VALUES (1), (1.1), (0.9), (NULL), (NULL), (2.1), (NULL), (2.0), (2.05), (3.11), (2.99), (3.05), (NULL)) as t(v);
  v   | rolling_median_impute 
------+-----------------------
    1 |                     1
  1.1 |                   1.1
  0.9 |                   0.9
      |                   1.1
      |                   1.1
  2.1 |                   2.1
      |                     2
  2.0 |                     2
 2.05 |                  2.05
 3.11 |                  3.11
 2.99 |                  2.99
 3.05 |                  3.05
      |                  3.05
(13 rows)

SELECT v,  rolling_median_impute(v::double precision, 3) over() FROM (VALUES (NULL), (NULL), (NULL)) as t(v);
ERROR:  Too few non-nulls
DETAIL:  window size 3 is greater than total number of non-null elements in partition: 0
HINT:  reduce window size
SELECT v, rolling_median_impute(v, 3) over() FROM (VALUES (9343667.56611), (9357699.85564), (NULL), (9299919.02793), (9343667.56611), (NULL)) as t(v);
       v       | rolling_median_impute
---------------+-----------------------
 9343667.56611 |         9343667.56611
 9357699.85564 |         9357699.85564
               |         9343667.56611
 9299919.02793 |         9299919.02793
 9343667.56611 |         9343667.56611
               |         9343667.56611
(6 rows)

SELECT v, rolling_median_impute(v, 3) over() FROM (VALUES (9299919.02793), (9487695.75227), (NULL), (9108079.13911), (NULL), (9284030.27181)) as t(v);
       v       | rolling_median_impute
---------------+-----------------------
 9299919.02793 |         9299919.02793
 9487695.75227 |         9487695.75227
               |         9299919.02793
 9108079.13911 |         9108079.13911
               |         9284030.27181
 9284030.27181 |         9284030.27181
(6 rows)

SELECT v, rolling_median_impute(v, 3) over() FROM (VALUES (NULL), (91), (96), (93), (96), (NULL)) as t(v);
 v  | rolling_median_impute 
----+-----------------------
    |                    93
 91 |                    91
 96 |                    96
 93 |                    93
 96 |                    96
    |                    96
(6 rows)