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Updated Examples and Recipes (markdown)

HowardHinnant
2015-08-02 11:55:19 -04:00
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Examples-and-Recipes.md

@@ -188,7 +188,7 @@ Here is a function to perform that conversion:
The variable `utc` holds the “year + us” as a time point with microseconds precision. This time point counts microseconds, including leap seconds, since 1970-01-01 00:00:00 UTC. The variable `utc` holds the “year + us” as a time point with microseconds precision. This time point counts microseconds, including leap seconds, since 1970-01-01 00:00:00 UTC.
The next step is find when the day started that is associated with `utc`. To do this one must convert `utc` back to “Unix time”, and then truncate that time point to a precision of `days`, resulting in the variable `dp`. `dp` is a count of days since 1970-01-01. Since the required epoch is 1958-01-01, this is taken into account in creating `d`, the first value needed in the return type. The next step is to find when the day started that is associated with `utc`. To do this one must convert `utc` back to “Unix time”, and then truncate that time point to a precision of `days`, resulting in the variable `dp`. `dp` is a count of days since 1970-01-01. Since the required epoch is 1958-01-01, this is taken into account in creating `d`, the first value needed in the return type.
Now the number of microseconds since the start of the day needs to be computed. The start of the day, `dp`, is converted back into the leap-second aware system, and subtracted from the microsecond time point: `utc`. The variable `us` is reused to hold “microseconds since midnight”. Now it is a simple computation to split this into milliseconds since midnight, and microseconds since the last millisecond. Now the number of microseconds since the start of the day needs to be computed. The start of the day, `dp`, is converted back into the leap-second aware system, and subtracted from the microsecond time point: `utc`. The variable `us` is reused to hold “microseconds since midnight”. Now it is a simple computation to split this into milliseconds since midnight, and microseconds since the last millisecond.