How to update one column in table from select statement?

Question

I have a table that looks like this:

utc date                       est date
2018-03-01 07:06:38.000
2018-03-01 07:07:38.000

est date is blank. I have a select statement that calculates EST time.

How do i update the est date column from my select statement?

SELECT toCONVERT(datetime, 
               SWITCHOFFSET(CONVERT(datetimeoffset, 
                                    table."utc date"), 
                            DATENAME(TzOffset, SYSDATETIMEOFFSET())))
       as "etc date"
FROM table where  "utc date" > '2017-10-01' 

Answer 1

UPDATE syntax:

UPDATE [table]
SET [est date] = toCONVERT(datetime, 
                           SWITCHOFFSET(CONVERT(datetimeoffset, table.[utc date]), 
                           DATENAME(TzOffset, SYSDATETIMEOFFSET())))
WHERE [utc date] > '2017-10-01'