To most of us it's almost dogmatic that $H can't be negative!
This is correct concerning the COS Special Variable $HOROLOG.
No doubt. It's the presentation of the actual date & time.
http://docs.intersystems.com/latest/csp/docbook/DocBook.UI.Page.cls?KEY…
For dates before 1841 it's suggested to use Julian date before 1841.
Good for calculations.
But what about values in $H_format ?
Conversion functions $ZD(), $ZDT(), $ZDH(), $ZDTH() and
for SQL $system.SQL.TOCHAR() and $system.SQL.TODATE()
take care of the conversion to human readable date. You know this.
But Julian date as input i
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