Trunc

Truncate a number or time to the next lower unit.

Syntax

Trunc(x [, unit])

Arguments

• x

  An integer or real number, time expression, or time period.

• unit

  Optional. The size of the unit to truncate to; x will be truncated to a multiple of unit. If x is a number, unit must be a number. If x is a time expression or time period, unit must be a time period. If unit is omitted, Trunc truncates to the next lower integer (for a number) or second (for a time period).

Returns

The largest multiple of unit that is less than x. For a negative x, it returns the lowest multiple of unit larger than x. The return is the same data type as x.

Exceptions

If x is a string, or if unit is of the wrong data type, an error is returned.

Notes

If x is a time, and unit is omitted, this routine has no effect, as times are only accurate to one second.

When |x| < |unit|, 0 is returned.

Example

• Trunc(12.999)

  [Returns 12, truncated to the next lower integer]

• Trunc(28.75, 10)

  [Returns 20, truncated to next lower multiple of 10]

• Trunc('14-Dec-16 11:47', '+1h')

  [Returns 12/14/2016 11:00:00 AM, truncated to next lower hour]

• Trunc('18:47'-'15:00','+1h')

  [Returns 03:00:00, truncated period to next lower hour]

  Note: Truncating to the next lower day results in a timestamp of the next lower day in UTC time, not local time.