Parsing Numeric Date Time Format

[Maria Lee]

Hello,

I am new to Stata and am working with a pre-existing dataset. I am trying to figure out how a particular numeric date-time variable was converted from a string variable d_date_start_s, as I want to use the same method to convert a new set of string date-time values into numeric form. An example of the string value format is "Jan 27, 2023 7:38:03 am", which has the corresponding numeric value 23037. I tried to construct a new numeric variable from d_date_start_s to see if it would give me the same format by running

generate double numvar = clock(d_date_start_s, "MDYhms")

but this just generated missing values.

As far as I can tell, the Datetime Conversion manual doesn't include this exact string date/time format so any help would be appreciated.

[Clyde Schechter]

Well, 23037 is not the numeric value corresponding to the date-time Jan 27, 2023 7:38:03 am. It is the numeric value corresponding to just the date Jan 27,2023.

I tried to construct a new numeric variable from d_date_start_s to see if it would give me the same format by running

generate double numvar = clock(d_date_start_s, "MDYhms")

but this just generated missing values.

I cannot replicate this in my setup. This code, with the example value of d_date_start_s "Jan 27, 2023 7:38:03 am" gives me a non-missing numeric value which, when formatted %tc, displays correctly as Jan 27 2023 7:38:03 am:

.    * Example generated by -dataex-. For more info, type help    dataex
.    clear

.    input str23 str_date_time

    str_date_time
    1. "Jan 27, 2023 7:38:03 am"
    2. end

.
.    gen double num_date_time = clock(str_date_time, "MDYhms")

.    list

    
    str_date_time   num_dat~e
    -
    1.  Jan 27, 2023 7:38:03 am   1.990e+12
    

.    format num_date_time %tc

.    list

    
    str_date_time        num_date_time
    -
    1.  Jan 27, 2023 7:38:03 am   27jan2023 07:38:03
    

.

To get to the desired result, 23037, one need only then extract the date:

. gen num_date = dofc(num_date_time)

. list

     +---------------------------------------------------------+
     |           str_date_time        num_date_time   num_date |
     |---------------------------------------------------------|
  1. | Jan 27, 2023 7:38:03 am   27jan2023 07:38:03      23037 |
     +---------------------------------------------------------+

. format num_date %td

. list

     +----------------------------------------------------------+
     |           str_date_time        num_date_time    num_date |
     |----------------------------------------------------------|
  1. | Jan 27, 2023 7:38:03 am   27jan2023 07:38:03   27jan2023 |
     +----------------------------------------------------------+

.

[Maria Lee]

Ah, thank you so much! I just needed to use the format command. Thanks also for showing me how to extract the date.