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- Date operators
- + , -, Second, Minute, Hour, Day, DateUnit, DateFormat, Date, ToTimeUnit.
- Usage
- d1 + nb
d1 - nb
d1 - d2
Date(stg)
ToTimeUnit(i)
- Arguments
- d1, d2 (DATE)
nb, i (INT)
stg
Second, Minute, Hour, Day (INT): definition of classical date units in terms of integers.
DateUnit(INT): value of the current date unit.
DateFormat(STRING): STRING indicating the format of dates currently used in the system.
- Returned Object
- The addition/substraction of a date and an integer returns a DATE. The new date is the old date incremented/decremented by nb times DateUnit.
The difference between two dates returns an INT corresponding to the number of DateUnit between these two dates. This difference can be a negative integer.
Second = 1, Minute = 60, Hour = 3600, Day = 86400 are global constant values.
Global variables and their default values: DateFormat = ''DDMMYY'', DateUnit = 86400. These values are used as parameters by other date functions.
The value returned by Date() is an INT corresponding to the integer encoding of a date defined as a STRING. If stg is Undef, returns Undef.
The value returned by ToTimeUnit is the conversion of number i into a corresponding number of DateUnits. If i is Undef, returns Undef.
- Description
- DateUnit is given the default value Day. It may be changed to other values, for example DateUnit = Hour. Once a DateUnit is fixed, other date functions can be used. The DateUnit is implicitly used as a global variable by the other functions when necessary (e.g. in incrementation of dates, or integer conversions to dates).
Function Date() converts a STRING into a date. It uses the current value of DateFormat to encode strings as DATE objects. Valid values of DateFormat are strings: ''DDMM'', ''DDMMYY'', ''MMYY'', ''DDMMTIME'', ''DDMMYYTIME''. A date STRING with format DDMMYY is a STRING like ''09/07/97'', where '/' is a mandatory separator between date fields. A time STRING is a series of 1 to 3 integers separated by a ':'. Valid time strings are ''12:35:01'', ''12:35:'', ''12:35'' or ''12''. Whenever time information is used, e.g. DateFormat = DDMMTIME, valid time strings have to be concatenated to date strings, separated by a white space: e.g. ''09/07 12:35:01''.
- Note
- Dates have to be greater than 01/01/1901.
- See Also
- MTG module:
DateSample,
FirstDefinedFeature,
LastDefinedFeature,
NextDate,
PreviousDate
Examples
AML>DateUnit
<INT>86400
AML> DateFormat
<STRING>DDMMTIME
AML> d1 = Date("10/0912:33")
<DATE> 10/09 12:33
AML> DateFormat
<STRING>DDMMYY
AML> d1 = Date("10/09/97")
<DATE> 10/09/97
AML> # Adding 10 days to d1
AML> d2 = d1 + 10
<DATE> 20/09/97
AML> d2 - d1
<INT>10
AML> DateUnit = Minute
<INT>60
AML> ToTimeUnit(420)
<INT>7
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