Generate and return the day number of the week of a Gregorian Calendar date, assuming Sunday is the zeroth day of the week. If there is no input argument, then the current day number of the week is returned. More...

Detailed Description

Generate and return the day number of the week of a Gregorian Calendar date, assuming Sunday is the zeroth day of the week. If there is no input argument, then the current day number of the week is returned.

The internationally recognized method of conveying the day of the week is governed by ISO 8601, which uses the Zeller congruence algorithm for calculating the day of a week in a particular month and year, invented by Christian Zeller.
Monday is the official first day of the week according to ISO 8601.

To get an ISO-compliant day of week, see getWeekDayISO.

Parameters

[in]	values	: The input `contiguous` array of shape `(:)`, of size `3` or larger, of type `integer` of default kind IK, containing the `[year, month, day]` triple of the Gregorian calendar. For the current local date, this triple can be obtained from the Fortran intrinsic `date_and_time()` or getDateTime(). Only the first three elements (`values(1:3)`) are used to compute the output. The ability to pass longer vectors as input is to allow the output `values(1:8)` of various functionalities of this module to be passed directly to the procedures under this generic interface. (optional. It can be present if and only if all other input arguments are missing.)
[in]	year	: The input scalar, or array of the same shape as other array-like arguments, of type `integer` of default kind IK, containing the year of the Gregorian calendar. (optional. It can be present if and only if the input argument `values` is missing.)
[in]	month	: The input scalar, or array of the same shape as other array-like arguments, of type `integer` of default kind IK, containing the month of the Gregorian calendar. (optional. It must be present if and only if the input argument `year` is present.)
[in]	day	: The input scalar, or array of the same shape as other array-like arguments, of type `integer` of default kind IK, containing the day of the Gregorian calendar. (optional. It must be present if and only if the input argument `month` is present.)

Returns: weekday : The output scalar or array of the same shape as the input array-like arguments (except values), of type integer of default kind IK, containing the day of the week, starting with Sunday as day number 0.

Possible calling interfaces ⛓

: use pm_dateTime, only: getWeekDay

integer(IK) :: weekday

weekday = getWeekDay() ! current date it used.

weekday = getWeekDay(values(1:3)) ! values = [year, month, day]

weekday = getWeekDay(year, month, day) ! elemental

!

pm_dateTime::getWeekDay
Generate and return the day number of the week of a Gregorian Calendar date, assuming Sunday is the z...
Definition: pm_dateTime.F90:3436

pm_dateTime
This module contains classes and procedures for computing, manipulating, and styling dates and times.
Definition: pm_dateTime.F90:308

Warning: The size of the input argument values(:) must be at least 3 and at most 8.
The input values for the year, month, and day must be valid values.
The input month must be a number between 1 and 12.
The input day must be a number between 1 and 31.
These conditions are verified only if the library is built with the preprocessor macro CHECK_ENABLED=1.; The pure procedure(s) documented herein become impure when the ParaMonte library is compiled with preprocessor macro CHECK_ENABLED=1.
By default, these procedures are pure in release build and impure in debug and testing builds.

Remarks: The procedures under discussion are elemental. The procedures under this generic interface are non-elemental when the input argument values(:) is present.

See also: getWeekDayISO
WEEKDAY_NAME_ISO
WEEKDAY_NAME
strftime

Example usage ⛓

: 1program example

2

3 use pm_kind, only: SK, IK

4 use pm_io, only: display_type

5 use pm_dateTime, only: WEEKDAY_NAME

6 use pm_dateTime, only: getWeekDay

7

8 implicit none

9

10 integer(IK) :: Values(8)

11 type(display_type) :: disp

12 disp = display_type(file = "main.out.F90")

13

14 call disp%skip()

15 call disp%show("!%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%")

16 call disp%show("! Get the day number of the week of a Gregorian calendar date, assuming Monday is the first day of the week.")

17 call disp%show("!%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%")

18 call disp%skip()

19

20 call disp%skip()

21 call disp%show("getWeekDay()")

22 call disp%show( getWeekDay() )

23 call disp%show("trim(WEEKDAY_NAME(getWeekDay())) ! current day of week.")

24 call disp%show( trim(WEEKDAY_NAME(getWeekDay())) , deliml = SK_"""" )

25 call disp%skip()

26

27 call disp%skip()

28 call disp%show("call date_and_time(values = Values(1:8))")

29 call date_and_time(values = Values(1:8))

30 call disp%show("getWeekDay(Values(1:3))")

31 call disp%show( getWeekDay(Values(1:3)) )

32 call disp%show("getWeekDay(year = Values(1), month = Values(2), day = Values(3))")

33 call disp%show( getWeekDay(year = Values(1), month = Values(2), day = Values(3)) )

34 call disp%show("SK_'Today is '//trim(WEEKDAY_NAME(getWeekDay(Values(1:3))))//SK_'.'")

35 call disp%show( SK_'Today is '//trim(WEEKDAY_NAME(getWeekDay(Values(1:3))))//SK_'.' , deliml = SK_"""" )

36 call disp%skip()

37

38 call disp%skip()

39 call disp%show("getWeekDay(1582_IK, 10_IK, 15_IK)")

40 call disp%show( getWeekDay(1582_IK, 10_IK, 15_IK) )

41 call disp%show("trim(WEEKDAY_NAME(getWeekDay(1582_IK, 10_IK, 15_IK)))//SK_' October 15, 1582 is the first day of the Gregorian Calendar.'")

42 call disp%show( trim(WEEKDAY_NAME(getWeekDay(1582_IK, 10_IK, 15_IK)))//SK_' October 15, 1582 is the first day of the Gregorian Calendar.' , deliml = SK_"""" )

43 call disp%skip()

44

45 call disp%skip()

46 call disp%show("getWeekDay(1_IK, 1_IK, 1_IK)")

47 call disp%show( getWeekDay(1_IK, 1_IK, 1_IK) )

48 call disp%show("SK_'January 1, 0001 is a '//trim(WEEKDAY_NAME(getWeekDay(1_IK, 1_IK, 1_IK)))//SK_' in the proleptic Gregorian Calendar.'")

49 call disp%show( SK_'January 1, 0001 is a '//trim(WEEKDAY_NAME(getWeekDay(1_IK, 1_IK, 1_IK)))//SK_' in the proleptic Gregorian Calendar.' , deliml = SK_"""" )

50 call disp%skip()

51

52 call disp%skip()

53 call disp%show("getWeekDay(2000_IK, 1_IK, 1_IK)")

54 call disp%show( getWeekDay(2000_IK, 1_IK, 1_IK) )

55 call disp%show("trim(WEEKDAY_NAME(getWeekDay(2000_IK, 1_IK, 1_IK)))")

56 call disp%show( trim(WEEKDAY_NAME(getWeekDay(2000_IK, 1_IK, 1_IK))) , deliml = SK_"""" )

57 call disp%skip()

58

59end program example

pm_io::show
This is a generic method of the derived type display_type with pass attribute.
Definition: pm_io.F90:11726

pm_io::skip
This is a generic method of the derived type display_type with pass attribute.
Definition: pm_io.F90:11508

pm_dateTime::WEEKDAY_NAME
character(9, SK), dimension(0:6), parameter WEEKDAY_NAME
The character constant vector of shape (0:6) of length type parameter 9 containing the names of the d...
Definition: pm_dateTime.F90:382

pm_io
This module contains classes and procedures for input/output (IO) or generic display operations on st...
Definition: pm_io.F90:252

pm_io::disp
type(display_type) disp
This is a scalar module variable an object of type display_type for general display.
Definition: pm_io.F90:11393

pm_kind
This module defines the relevant Fortran kind type-parameters frequently used in the ParaMonte librar...
Definition: pm_kind.F90:268

pm_kind::IK
integer, parameter IK
The default integer kind in the ParaMonte library: int32 in Fortran, c_int32_t in C-Fortran Interoper...
Definition: pm_kind.F90:540

pm_kind::SK
integer, parameter SK
The default character kind in the ParaMonte library: kind("a") in Fortran, c_char in C-Fortran Intero...
Definition: pm_kind.F90:539

pm_io::display_type
Generate and return an object of type display_type.
Definition: pm_io.F90:10282

Example Unix compile command via Intel ifort compiler ⛓
1#!/usr/bin/env sh

2rm main.exe

3ifort -fpp -standard-semantics -O3 -Wl,-rpath,../../../lib -I../../../inc main.F90 ../../../lib/libparamonte* -o main.exe

4./main.exe

Example Windows Batch compile command via Intel ifort compiler ⛓
1del main.exe

2set PATH=..\..\..\lib;%PATH%

3ifort /fpp /standard-semantics /O3 /I:..\..\..\include main.F90 ..\..\..\lib\libparamonte*.lib /exe:main.exe

4main.exe

Example Unix / MinGW compile command via GNU gfortran compiler ⛓
1#!/usr/bin/env sh

2rm main.exe

3gfortran -cpp -ffree-line-length-none -O3 -Wl,-rpath,../../../lib -I../../../inc main.F90 ../../../lib/libparamonte* -o main.exe

4./main.exe

Example output ⛓
1

2!%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

3! Get the day number of the week of a Gregorian calendar date, assuming Monday is the first day of the week.

4!%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

5

6

7getWeekDay()

8+0

9trim(WEEKDAY_NAME(getWeekDay())) ! current day of week.

10"Sunday"

11

12

13call date_and_time(values = Values(1:8))

14getWeekDay(Values(1:3))

15+0

16getWeekDay(year = Values(1), month = Values(2), day = Values(3))

17+0

18SK_'Today is '//trim(WEEKDAY_NAME(getWeekDay(Values(1:3))))//SK_'.'

19"Today is Sunday."

20

21

22getWeekDay(1582_IK, 10_IK, 15_IK)

23+5

24trim(WEEKDAY_NAME(getWeekDay(1582_IK, 10_IK, 15_IK)))//SK_' October 15, 1582 is the first day of the Gregorian Calendar.'

25"Friday October 15, 1582 is the first day of the Gregorian Calendar."

26

27

28getWeekDay(1_IK, 1_IK, 1_IK)

29+1

30SK_'January 1, 0001 is a '//trim(WEEKDAY_NAME(getWeekDay(1_IK, 1_IK, 1_IK)))//SK_' in the proleptic Gregorian Calendar.'

31"January 1, 0001 is a Monday in the proleptic Gregorian Calendar."

32

33

34getWeekDay(2000_IK, 1_IK, 1_IK)

35+6

36trim(WEEKDAY_NAME(getWeekDay(2000_IK, 1_IK, 1_IK)))

37"Saturday"

38

39

Test:: test_pm_dateTime

Final Remarks ⛓

If you believe this algorithm or its documentation can be improved, we appreciate your contribution and help to edit this page's documentation and source file on GitHub.
For details on the naming abbreviations, see this page.
For details on the naming conventions, see this page.
This software is distributed under the MIT license with additional terms outlined below.

If you use any parts or concepts from this library to any extent, please acknowledge the usage by citing the relevant publications of the ParaMonte library.
If you regenerate any parts/ideas from this library in a programming environment other than those currently supported by this ParaMonte library (i.e., other than C, C++, Fortran, MATLAB, Python, R), please also ask the end users to cite this original ParaMonte library.

This software is available to the public under a highly permissive license.
Help us justify its continued development and maintenance by acknowledging its benefit to society, distributing it, and contributing to it.

Copyright: Computational Data Science Lab

Author:: Amir Shahmoradi, March 22, 2012, 00:00 AM, National Institute for Fusion Studies, The University of Texas Austin

Definition at line 3436 of file pm_dateTime.F90.

The documentation for this interface was generated from the following file:

src/fortran/main/pm_dateTime.F90