Kuwaiti algorithm - Revision history

Hellbus: ←Redirected page to Tabular Islamic calendar#Kuwaiti algorithm

2012-12-25T21:13:35Z

←Redirected page to Tabular Islamic calendar#Kuwaiti algorithm

← Previous revision		Revision as of 21:13, 25 December 2012
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	#REDIRECT [[Tabular Islamic calendar]]		#REDIRECT [[Tabular Islamic calendar#Kuwaiti algorithm]]
	[[Category:Islamic calendar]]		[[Category:Islamic calendar]]
	[[Category:Calendar algorithms]]		[[Category:Calendar algorithms]]

Dbachmann: ←Redirected page to Tabular Islamic calendar

2012-04-11T07:28:00Z

←Redirected page to Tabular Islamic calendar

← Previous revision		Revision as of 07:28, 11 April 2012
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			#REDIRECT [[Tabular Islamic calendar]]
	{{notability}}
	~~{{merge\|Tabular~~ Islamic calendar}}		[[Category:Islamic calendar]]
	The '''Kuwaiti algorithm''' is used by [[Microsoft]] to convert between [[Gregorian calendar]] dates and [[Islamic calendar]] dates.<ref>[http://www.microsoft.com/globaldev/DrIntl/columns/002/default.mspx#EAD Hijri Dates in SQL Server 2000] from Microsoft{{dead link}}</ref><ref>Kriegel, Alex, and Boris M. Trukhnov. SQL Bible. Indianapolis, IN: Wiley, 2008. Page 383.</ref> There is no fixed correspondence defined in advance between the Gregorian [[solar calendar]] and the Islamic [[lunar calendar]], since the latter is defined by the visibility of the new moon by religious authorities and can therefore vary by a day or two, depending on the particular Islamic authority, weather conditions, and other variables. As an attempt to make conversions between the calendars somewhat predictable, Microsoft claims to have created this [[algorithm]] based on statistical analysis of historical data from [[Kuwait]].

	According to Robert Harry van Gent at Utrecht University, the so-called "Kuwaiti algorithm" is simply an implementation of a standard [[tabular Islamic calendar]] algorithm used in Islamic astronomical tables since the 11th century.<ref>"Microsoft gives no details on the mathematics of the “Kuwaiti Algorithm” but one can easily demonstrate that it is based on the standard arithmetical scheme (type Ia) which has been used in Islamic astronomical tables since the 11th century CE. Naming this algorithm the “Kuwaiti Algorithm” is thus historically incorrect and should be discontinued." [http://www.staff.science.uu.nl/~gent0113/islam/islam_tabcal.htm Islamic-Western Calendar Converter (Based on the Arithmetical or Tabular Calendar)]</ref>

	==References==
	{{reflist}}

	[[Category:Specific calendars]]
	[[Category:Calendar algorithms]]		[[Category:Calendar algorithms]]

Dbachmann at 07:19, 11 April 2012

2012-04-11T07:19:35Z

← Previous revision		Revision as of 07:19, 11 April 2012
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	{{notability}}		{{notability}}
	{{merge\|Tabular Islamic calendar}}		{{merge\|Tabular Islamic calendar}}
	The '''Kuwaiti algorithm''' is used by [[Microsoft]] to convert between [[Gregorian calendar]] dates and [[Islamic calendar]] dates.<ref>[http://www.microsoft.com/globaldev/DrIntl/columns/002/default.mspx#EAD Hijri Dates in SQL Server 2000] from Microsoft{{dead link}}</ref><ref>Kriegel, Alex, and Boris M. Trukhnov. SQL Bible. Indianapolis, IN: Wiley, 2008. Page 383.</ref> There is no fixed correspondence defined in advance between the Gregorian [[solar calendar]] and the Islamic [[lunar calendar]], since the latter is defined by the visibility of the new moon by religious authorities and can therefore vary by a day or two, depending on the particular Islamic authority, weather conditions, and other variables. As an attempt to make conversions between the calendars somewhat predictable, Microsoft claims to have created this [[algorithm]] based on statistical analysis of historical data from [[Kuwait]]. However, its results are identical to a variation of the [[tabular Islamic calendar]], which was introduced by Muslim astronomers around the eighth century.<ref>[http://www.staff.science.uu.nl/~gent0113/islam/islam_tabcal.htm The "Kuwait algorithm" in Islamic-Western Calendar Converter by Robert van Gent]</ref>		The '''Kuwaiti algorithm''' is used by [[Microsoft]] to convert between [[Gregorian calendar]] dates and [[Islamic calendar]] dates.<ref>[http://www.microsoft.com/globaldev/DrIntl/columns/002/default.mspx#EAD Hijri Dates in SQL Server 2000] from Microsoft{{dead link}}</ref><ref>Kriegel, Alex, and Boris M. Trukhnov. SQL Bible. Indianapolis, IN: Wiley, 2008. Page 383.</ref> There is no fixed correspondence defined in advance between the Gregorian [[solar calendar]] and the Islamic [[lunar calendar]], since the latter is defined by the visibility of the new moon by religious authorities and can therefore vary by a day or two, depending on the particular Islamic authority, weather conditions, and other variables. As an attempt to make conversions between the calendars somewhat predictable, Microsoft claims to have created this [[algorithm]] based on statistical analysis of historical data from [[Kuwait]].

	According to Robert Harry van Gent at Utrecht University, the so-called "Kuwaiti algorithm" is simply an implementation of a standard [[tabular Islamic calendar]] algorithm used in Islamic astronomical tables since the 11th century.<ref>"Microsoft gives no details on the mathematics of the “Kuwaiti Algorithm” but one can easily demonstrate that it is based on the standard arithmetical scheme (type Ia) which has been used in Islamic astronomical tables since the 11th century CE. Naming this algorithm the “Kuwaiti Algorithm” is thus historically incorrect and should be discontinued." [http://www.staff.science.uu.nl/~gent0113/islam/islam_tabcal.htm Islamic-Western Calendar Converter (Based on the Arithmetical or Tabular Calendar)]</ref>		According to Robert Harry van Gent at Utrecht University, the so-called "Kuwaiti algorithm" is simply an implementation of a standard [[tabular Islamic calendar]] algorithm used in Islamic astronomical tables since the 11th century.<ref>"Microsoft gives no details on the mathematics of the “Kuwaiti Algorithm” but one can easily demonstrate that it is based on the standard arithmetical scheme (type Ia) which has been used in Islamic astronomical tables since the 11th century CE. Naming this algorithm the “Kuwaiti Algorithm” is thus historically incorrect and should be discontinued." [http://www.staff.science.uu.nl/~gent0113/islam/islam_tabcal.htm Islamic-Western Calendar Converter (Based on the Arithmetical or Tabular Calendar)]</ref>

Dbachmann at 07:19, 11 April 2012

2012-04-11T07:19:16Z

← Previous revision		Revision as of 07:19, 11 April 2012
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	{{merge\|Tabular Islamic calendar}}		{{merge\|Tabular Islamic calendar}}
	The '''Kuwaiti algorithm''' is used by [[Microsoft]] to convert between [[Gregorian calendar]] dates and [[Islamic calendar]] dates.<ref>[http://www.microsoft.com/globaldev/DrIntl/columns/002/default.mspx#EAD Hijri Dates in SQL Server 2000] from Microsoft{{dead link}}</ref><ref>Kriegel, Alex, and Boris M. Trukhnov. SQL Bible. Indianapolis, IN: Wiley, 2008. Page 383.</ref> There is no fixed correspondence defined in advance between the Gregorian [[solar calendar]] and the Islamic [[lunar calendar]], since the latter is defined by the visibility of the new moon by religious authorities and can therefore vary by a day or two, depending on the particular Islamic authority, weather conditions, and other variables. As an attempt to make conversions between the calendars somewhat predictable, Microsoft claims to have created this [[algorithm]] based on statistical analysis of historical data from [[Kuwait]]. However, its results are identical to a variation of the [[tabular Islamic calendar]], which was introduced by Muslim astronomers around the eighth century.<ref>[http://www.staff.science.uu.nl/~gent0113/islam/islam_tabcal.htm The "Kuwait algorithm" in Islamic-Western Calendar Converter by Robert van Gent]</ref>		The '''Kuwaiti algorithm''' is used by [[Microsoft]] to convert between [[Gregorian calendar]] dates and [[Islamic calendar]] dates.<ref>[http://www.microsoft.com/globaldev/DrIntl/columns/002/default.mspx#EAD Hijri Dates in SQL Server 2000] from Microsoft{{dead link}}</ref><ref>Kriegel, Alex, and Boris M. Trukhnov. SQL Bible. Indianapolis, IN: Wiley, 2008. Page 383.</ref> There is no fixed correspondence defined in advance between the Gregorian [[solar calendar]] and the Islamic [[lunar calendar]], since the latter is defined by the visibility of the new moon by religious authorities and can therefore vary by a day or two, depending on the particular Islamic authority, weather conditions, and other variables. As an attempt to make conversions between the calendars somewhat predictable, Microsoft claims to have created this [[algorithm]] based on statistical analysis of historical data from [[Kuwait]]. However, its results are identical to a variation of the [[tabular Islamic calendar]], which was introduced by Muslim astronomers around the eighth century.<ref>[http://www.staff.science.uu.nl/~gent0113/islam/islam_tabcal.htm The "Kuwait algorithm" in Islamic-Western Calendar Converter by Robert van Gent]</ref>

			According to Robert Harry van Gent at Utrecht University, the so-called "Kuwaiti algorithm" is simply an implementation of a standard [[tabular Islamic calendar]] algorithm used in Islamic astronomical tables since the 11th century.<ref>"Microsoft gives no details on the mathematics of the “Kuwaiti Algorithm” but one can easily demonstrate that it is based on the standard arithmetical scheme (type Ia) which has been used in Islamic astronomical tables since the 11th century CE. Naming this algorithm the “Kuwaiti Algorithm” is thus historically incorrect and should be discontinued." [http://www.staff.science.uu.nl/~gent0113/islam/islam_tabcal.htm Islamic-Western Calendar Converter (Based on the Arithmetical or Tabular Calendar)]</ref>

	==References==		==References==

Dbachmann at 07:16, 11 April 2012

2012-04-11T07:16:23Z

← Previous revision		Revision as of 07:16, 11 April 2012
Line 2:		Line 2:
	{{merge\|Tabular Islamic calendar}}		{{merge\|Tabular Islamic calendar}}
	The '''Kuwaiti algorithm''' is used by [[Microsoft]] to convert between [[Gregorian calendar]] dates and [[Islamic calendar]] dates.<ref>[http://www.microsoft.com/globaldev/DrIntl/columns/002/default.mspx#EAD Hijri Dates in SQL Server 2000] from Microsoft{{dead link}}</ref><ref>Kriegel, Alex, and Boris M. Trukhnov. SQL Bible. Indianapolis, IN: Wiley, 2008. Page 383.</ref> There is no fixed correspondence defined in advance between the Gregorian [[solar calendar]] and the Islamic [[lunar calendar]], since the latter is defined by the visibility of the new moon by religious authorities and can therefore vary by a day or two, depending on the particular Islamic authority, weather conditions, and other variables. As an attempt to make conversions between the calendars somewhat predictable, Microsoft claims to have created this [[algorithm]] based on statistical analysis of historical data from [[Kuwait]]. However, its results are identical to a variation of the [[tabular Islamic calendar]], which was introduced by Muslim astronomers around the eighth century.<ref>[http://www.staff.science.uu.nl/~gent0113/islam/islam_tabcal.htm The "Kuwait algorithm" in Islamic-Western Calendar Converter by Robert van Gent]</ref>		The '''Kuwaiti algorithm''' is used by [[Microsoft]] to convert between [[Gregorian calendar]] dates and [[Islamic calendar]] dates.<ref>[http://www.microsoft.com/globaldev/DrIntl/columns/002/default.mspx#EAD Hijri Dates in SQL Server 2000] from Microsoft{{dead link}}</ref><ref>Kriegel, Alex, and Boris M. Trukhnov. SQL Bible. Indianapolis, IN: Wiley, 2008. Page 383.</ref> There is no fixed correspondence defined in advance between the Gregorian [[solar calendar]] and the Islamic [[lunar calendar]], since the latter is defined by the visibility of the new moon by religious authorities and can therefore vary by a day or two, depending on the particular Islamic authority, weather conditions, and other variables. As an attempt to make conversions between the calendars somewhat predictable, Microsoft claims to have created this [[algorithm]] based on statistical analysis of historical data from [[Kuwait]]. However, its results are identical to a variation of the [[tabular Islamic calendar]], which was introduced by Muslim astronomers around the eighth century.<ref>[http://www.staff.science.uu.nl/~gent0113/islam/islam_tabcal.htm The "Kuwait algorithm" in Islamic-Western Calendar Converter by Robert van Gent]</ref>

	Inevitably, any arithmetic algorithm is imprecise, and results often differ by a day or two from observation or complex calculation.

	==References==		==References==

Dbachmann at 07:16, 11 April 2012

2012-04-11T07:16:03Z

← Previous revision		Revision as of 07:16, 11 April 2012
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			{{notability}}
⚫	The '''Kuwaiti algorithm''' is used by [[Microsoft]] to convert between [[Gregorian calendar]] dates and [[Islamic calendar]] dates.<ref>[http://www.microsoft.com/globaldev/DrIntl/columns/002/default.mspx#EAD Hijri Dates in SQL Server 2000] from Microsoft</ref><ref>Kriegel, Alex, and Boris M. Trukhnov. SQL Bible. Indianapolis, IN: Wiley, 2008. Page 383.</ref> There is no fixed correspondence defined in advance between the Gregorian [[solar calendar]] and the Islamic [[lunar calendar]], since the latter is defined by the visibility of the new moon by religious authorities and can therefore vary by a day or two, depending on the particular Islamic authority, weather conditions, and other variables. As an attempt to make conversions between the calendars somewhat predictable, Microsoft claims to have created this [[algorithm]] based on statistical analysis of historical data from [[Kuwait]]. However, its results are identical to a variation of the [[tabular Islamic calendar]], which was introduced by Muslim astronomers around the eighth century.<ref>[http://www.staff.science.uu.nl/~gent0113/islam/islam_tabcal.htm The "Kuwait algorithm" in Islamic-Western Calendar Converter by Robert van Gent]</ref>
			{{merge\|Tabular Islamic calendar}}
		⚫	The '''Kuwaiti algorithm''' is used by [[Microsoft]] to convert between [[Gregorian calendar]] dates and [[Islamic calendar]] dates.<ref>[http://www.microsoft.com/globaldev/DrIntl/columns/002/default.mspx#EAD Hijri Dates in SQL Server 2000] from Microsoft{{dead link}}</ref><ref>Kriegel, Alex, and Boris M. Trukhnov. SQL Bible. Indianapolis, IN: Wiley, 2008. Page 383.</ref> There is no fixed correspondence defined in advance between the Gregorian [[solar calendar]] and the Islamic [[lunar calendar]], since the latter is defined by the visibility of the new moon by religious authorities and can therefore vary by a day or two, depending on the particular Islamic authority, weather conditions, and other variables. As an attempt to make conversions between the calendars somewhat predictable, Microsoft claims to have created this [[algorithm]] based on statistical analysis of historical data from [[Kuwait]]. However, its results are identical to a variation of the [[tabular Islamic calendar]], which was introduced by Muslim astronomers around the eighth century.<ref>[http://www.staff.science.uu.nl/~gent0113/islam/islam_tabcal.htm The "Kuwait algorithm" in Islamic-Western Calendar Converter by Robert van Gent]</ref>

	Inevitably, any arithmetic algorithm is imprecise, and results often differ by a day or two from observation or complex calculation.		Inevitably, any arithmetic algorithm is imprecise, and results often differ by a day or two from observation or complex calculation.

Bkell: /* Behavior */ removed section—original research, tagged as such for two and a half years

2011-07-16T04:54:13Z

Behavior: removed section—original research, tagged as such for two and a half years

← Previous revision		Revision as of 04:54, 16 July 2011
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	Inevitably, any arithmetic algorithm is imprecise, and results often differ by a day or two from observation or complex calculation.		Inevitably, any arithmetic algorithm is imprecise, and results often differ by a day or two from observation or complex calculation.

	==Behavior==
	''Note: This was determined by inspection of the output of the software and is possibly wrong for dates that were not examined.'' {{Original research\|date=January 2009}}
	*Common (non-leap) years have 354 days. Leap years have 355 days.
	*Odd-numbered months of the year have 30 days. Even-numbered months have 29 days. Exception: the 12th month of a leap year has 30 days.
	*Eleven of every thirty years are leap years. The leap years are the years which are congruent modulo 30 to any of these numbers: 2, 5, 7, 10, 13, 15, 18, 21, 24, 26, 29. Thus, a 30-year cycle always lasts exactly (354×30)+11 = 10631 days.
	*Correlation with Gregorian calendar: the 1st of January 2000 (a Saturday) corresponds to the 25th of Ramadan 1420. (Ramadan is the ninth month of the Islamic lunar year.)

	==References==		==References==

AstroLynx: webaddress update

2011-06-07T08:53:22Z

webaddress update

← Previous revision		Revision as of 08:53, 7 June 2011
Line 1:		Line 1:
	The '''Kuwaiti algorithm''' is used by [[Microsoft]] to convert between [[Gregorian calendar]] dates and [[Islamic calendar]] dates.<ref>[http://www.microsoft.com/globaldev/DrIntl/columns/002/default.mspx#EAD Hijri Dates in SQL Server 2000] from Microsoft</ref><ref>Kriegel, Alex, and Boris M. Trukhnov. SQL Bible. Indianapolis, IN: Wiley, 2008. Page 383.</ref> There is no fixed correspondence defined in advance between the Gregorian [[solar calendar]] and the Islamic [[lunar calendar]], since the latter is defined by the visibility of the new moon by religious authorities and can therefore vary by a day or two, depending on the particular Islamic authority, weather conditions, and other variables. As an attempt to make conversions between the calendars somewhat predictable, Microsoft claims to have created this [[algorithm]] based on statistical analysis of historical data from [[Kuwait]]. However, its results are identical to a variation of the [[tabular Islamic calendar]], which was introduced by Muslim astronomers around the eighth century.<ref>[http://www.~~phys~~.uu.nl/~~~vgent~~/islam/~~islam_tabcal_main~~.htm~~#kuwait~~ The "Kuwait algorithm" in Islamic-Western Calendar Converter by Robert van Gent]</ref>		The '''Kuwaiti algorithm''' is used by [[Microsoft]] to convert between [[Gregorian calendar]] dates and [[Islamic calendar]] dates.<ref>[http://www.microsoft.com/globaldev/DrIntl/columns/002/default.mspx#EAD Hijri Dates in SQL Server 2000] from Microsoft</ref><ref>Kriegel, Alex, and Boris M. Trukhnov. SQL Bible. Indianapolis, IN: Wiley, 2008. Page 383.</ref> There is no fixed correspondence defined in advance between the Gregorian [[solar calendar]] and the Islamic [[lunar calendar]], since the latter is defined by the visibility of the new moon by religious authorities and can therefore vary by a day or two, depending on the particular Islamic authority, weather conditions, and other variables. As an attempt to make conversions between the calendars somewhat predictable, Microsoft claims to have created this [[algorithm]] based on statistical analysis of historical data from [[Kuwait]]. However, its results are identical to a variation of the [[tabular Islamic calendar]], which was introduced by Muslim astronomers around the eighth century.<ref>[http://www.staff.science.uu.nl/~gent0113/islam/islam_tabcal.htm The "Kuwait algorithm" in Islamic-Western Calendar Converter by Robert van Gent]</ref>

	Inevitably, any arithmetic algorithm is imprecise, and results often differ by a day or two from observation or complex calculation.		Inevitably, any arithmetic algorithm is imprecise, and results often differ by a day or two from observation or complex calculation.

Joe Kress: wording

2010-02-14T05:58:01Z

wording

← Previous revision		Revision as of 05:58, 14 February 2010
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	The '''Kuwaiti algorithm''' is ~~a tool~~ used by ~~the~~ ~~company~~ [[~~Microsoft~~]] <ref>[http://www.microsoft.com/globaldev/DrIntl/columns/002/default.mspx#EAD Hijri Dates in SQL Server 2000] from Microsoft</ref><ref>Kriegel, Alex, and Boris M. Trukhnov. SQL Bible. Indianapolis, IN: Wiley, 2008. Page 383.</ref> ~~to convert between dates in the Western standard [[Gregorian calendar]] and dates in the Hijri or [[Islamic calendar]].~~ There is no fixed correspondence defined in advance between the Gregorian [[solar calendar]] and the Islamic [[lunar calendar]], since the latter is defined by the visibility of the new moon by religious authorities and can therefore vary by a day or two, depending on the particular Islamic authority, weather conditions, and other variables. As an attempt to make conversions between the calendars somewhat predictable, Microsoft claims to have created this [[algorithm]] based on statistical analysis of historical data from [[Kuwait]]. However, its results are identical to a variation of the [[tabular Islamic calendar]], which was introduced by Muslim astronomers around the eighth century.<ref>[http://www.phys.uu.nl/~vgent/islam/islam_tabcal_main.htm#kuwait The "Kuwait algorithm" in Islamic-Western Calendar Converter by Robert van Gent]</ref>		The '''Kuwaiti algorithm''' is used by [[Microsoft]] to convert between [[Gregorian calendar]] dates and [[Islamic calendar]] dates.<ref>[http://www.microsoft.com/globaldev/DrIntl/columns/002/default.mspx#EAD Hijri Dates in SQL Server 2000] from Microsoft</ref><ref>Kriegel, Alex, and Boris M. Trukhnov. SQL Bible. Indianapolis, IN: Wiley, 2008. Page 383.</ref> There is no fixed correspondence defined in advance between the Gregorian [[solar calendar]] and the Islamic [[lunar calendar]], since the latter is defined by the visibility of the new moon by religious authorities and can therefore vary by a day or two, depending on the particular Islamic authority, weather conditions, and other variables. As an attempt to make conversions between the calendars somewhat predictable, Microsoft claims to have created this [[algorithm]] based on statistical analysis of historical data from [[Kuwait]]. However, its results are identical to a variation of the [[tabular Islamic calendar]], which was introduced by Muslim astronomers around the eighth century.<ref>[http://www.phys.uu.nl/~vgent/islam/islam_tabcal_main.htm#kuwait The "Kuwait algorithm" in Islamic-Western Calendar Converter by Robert van Gent]</ref>

	Inevitably, any arithmetic algorithm is imprecise, and results often differ by a day or two from observation or complex calculation.		Inevitably, any arithmetic algorithm is imprecise, and results often differ by a day or two from observation or complex calculation.

Lyc. cooperi: whoops, spacing issue

2010-02-14T04:50:05Z

whoops, spacing issue

← Previous revision		Revision as of 04:50, 14 February 2010
Line 1:		Line 1:
	The '''Kuwaiti algorithm'''is a tool used by the company [[Microsoft]] <ref>[http://www.microsoft.com/globaldev/DrIntl/columns/002/default.mspx#EAD Hijri Dates in SQL Server 2000] from Microsoft</ref><ref>Kriegel, Alex, and Boris M. Trukhnov. SQL Bible. Indianapolis, IN: Wiley, 2008. Page 383.</ref> to convert between dates in the Western standard [[Gregorian calendar]] and dates in the Hijri or [[Islamic calendar]]. There is no fixed correspondence defined in advance between the Gregorian [[solar calendar]] and the Islamic [[lunar calendar]], since the latter is defined by the visibility of the new moon by religious authorities and can therefore vary by a day or two, depending on the particular Islamic authority, weather conditions, and other variables. As an attempt to make conversions between the calendars somewhat predictable, Microsoft claims to have created this [[algorithm]] based on statistical analysis of historical data from [[Kuwait]]. However, its results are identical to a variation of the [[tabular Islamic calendar]], which was introduced by Muslim astronomers around the eighth century.<ref>[http://www.phys.uu.nl/~vgent/islam/islam_tabcal_main.htm#kuwait The "Kuwait algorithm" in Islamic-Western Calendar Converter by Robert van Gent]</ref>		The '''Kuwaiti algorithm''' is a tool used by the company [[Microsoft]] <ref>[http://www.microsoft.com/globaldev/DrIntl/columns/002/default.mspx#EAD Hijri Dates in SQL Server 2000] from Microsoft</ref><ref>Kriegel, Alex, and Boris M. Trukhnov. SQL Bible. Indianapolis, IN: Wiley, 2008. Page 383.</ref> to convert between dates in the Western standard [[Gregorian calendar]] and dates in the Hijri or [[Islamic calendar]]. There is no fixed correspondence defined in advance between the Gregorian [[solar calendar]] and the Islamic [[lunar calendar]], since the latter is defined by the visibility of the new moon by religious authorities and can therefore vary by a day or two, depending on the particular Islamic authority, weather conditions, and other variables. As an attempt to make conversions between the calendars somewhat predictable, Microsoft claims to have created this [[algorithm]] based on statistical analysis of historical data from [[Kuwait]]. However, its results are identical to a variation of the [[tabular Islamic calendar]], which was introduced by Muslim astronomers around the eighth century.<ref>[http://www.phys.uu.nl/~vgent/islam/islam_tabcal_main.htm#kuwait The "Kuwait algorithm" in Islamic-Western Calendar Converter by Robert van Gent]</ref>

	Inevitably, any arithmetic algorithm is imprecise, and results often differ by a day or two from observation or complex calculation.		Inevitably, any arithmetic algorithm is imprecise, and results often differ by a day or two from observation or complex calculation.