I would like to extract variants from a matrix table which have an empty filter field.
The type of this field is set.
If I extract filter elements with mt.row.filter.take(100) my first empty filter occurs at position 97.
If I check mt.row.filter.take(100) == set() I get True so I hoped the following query would work:
my_new_table = mt.filter_rows(mt.row.filters==set())
It returns an error though:
hail.expr.expressions.base_expression.ExpressionException: cannot impute array elements
I’ve tried a few other expressions I hoped would represent an empty set but I’m not confident with the syntax. I can see documentation about empty sets on the API but it’s over my head.
Does anyone have a way to get extract these empty filters?
Thanks for any help you can provide!