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harbour-core/harbour/doc/en/math.txt
2000-08-12 23:39:35 +00:00

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/*
* $Id$
*/
/*
* The following parts are Copyright of the individual authors.
* www - http://www.harbour-project.org
*
* Copyright 2000 Luiz Rafael Culik <culik@sl.conex.net>
* Documentation for: ABS(),EXP(),LOG(),INT(),MAX()
* MIN(),SQRT(),ROUND()
* See doc/license.txt for licensing terms.
*
*/
/* $DOC$
* $FUNCNAME$
* ABS()
* $CATEGORY$
* Math
* $ONELINER$
* Return the absolute value of a number.
* $SYNTAX$
* ABS(<nNumber>) --> <nAbsNumber>
* $ARGUMENTS$
* <nNumber> Any number.
* $RETURNS$
* <nAbsNumber> The absolute numeric value.
* $DESCRIPTION$
* This function yields the absolute value of the numeric value or
* expression <nNumber>.
* $EXAMPLES$
* Proc Main()
*
* Local nNumber:=50
* Local nNumber1:=27
* cls
*
* qout(nNumber-nNumber1)
* qout(nNumber1-nNumber)
* qout(ABS(nNumber-nNumber1))
* qout(ABSnNumber1-nNumber))
* qout(ABS( -1 * 345))
* </fixed>
* $STATUS$
* R
* $COMPLIANCE$
* This function is CA-Clipper compliant.
* $PLATFORMS$
* All
* $FILES$
* Library is rtl
* $SEEALSO$
* EXP()
* $END$
*/
/* $DOC$
* $FUNCNAME$
* EXP()
* $CATEGORY$
* Math
* $ONELINER$
* Calculates the value of e raised to the passed power.
* $SYNTAX$
* EXP( <nNumber> ) --> <nValue>
* $ARGUMENTS$
* <nNumber> Any real number.
* $RETURNS$
* <nValue> The anti-logarithm of <nNumber>
* $DESCRIPTION$
* This function returns the value of e raised to the power of
* <nNumber>. It is the inverse of LOG().
* $EXAMPLES$
* ? EXP(45)
* </fixed>
* $STATUS$
* R
* $COMPLIANCE$
* This function is CA-Clipper compliant.
* $PLATFORMS$
* All
* $FILES$
* Library is rtl
* $SEEALSO$
* LOG()
* $END$
*/
/* $DOC$
* $FUNCNAME$
* INT()
* $CATEGORY$
* Math
* $ONELINER$
* Return the integer port of a numeric value.
* $SYNTAX$
* INT( <nNumber> ) --> <nIntNumber>
* $ARGUMENTS$
* <nNumber> Any numeric value.
* $RETURNS$
* <nIntNumber> The integer portion of the numeric value.
* $DESCRIPTION$
* This function converts a numeric expression to an integer. All
* decimal digits are truncated. This function does not round a value
* upward or downward; it merely truncates a number at the decimal point.
* $EXAMPLES$
* SET Decimal to 5
* ? INT(632512.62541)
* ? INT(845414111.91440)
* </fixed>
* $STATUS$
* R
* $COMPLIANCE$
* This function is CA-Clipper compliant.
* $PLATFORMS$
* All
* $FILES$
* Library is rtl
* $SEEALSO$
* ROUND(),STRZERO()
* $END$
*/
/* $DOC$
* $FUNCNAME$
* LOG()
* $CATEGORY$
* Math
* $ONELINER$
* Returns the natural logarithm of a number.
* $SYNTAX$
* LOG( <nNumber> ) --> <nLog>
* $ARGUMENTS$
* <nNumber> Any numeric expression.
* $RETURNS$
* <nExponent> The natural logarithm of <nNumber>.
* $DESCRIPTION$
* This function returns the natural logarithm of the number <nNumber>.
* If <nNumber> is 0 or less than 0, a numeric overflow occurs,
* which is depicted on the display device as a series of asterisks.
* This function is the inverse of EXP().
* $EXAMPLES$
* ? LOG(632512)
* </fixed>
* $STATUS$
* R
* $COMPLIANCE$
* This function is CA-Clipper compliant.
* $PLATFORMS$
* All
* $FILES$
* Library is rtl
* $SEEALSO$
* EXP()
* $END$
*/
/* $DOC$
* $FUNCNAME$
* MAX()
* $CATEGORY$
* Math
* $ONELINER$
* Returns the maximum of two numbers or dates.
* $SYNTAX$
* MAX(<xValue>,<xValue1>) --> <xMax>
* $ARGUMENTS$
* <xValue> Any date or numeric value.
*
* <xValue1> Any date or numeric value (same type as <xValue>).
* $RETURNS$
* <xMax> The larger numeric (or later date) value.
* $DESCRIPTION$
* This function returns the larger of the two passed espressions. If
* <xValue> and <xValue1> are numeric data types, the value returned by
* this function will be a numeric data type as well and will be the
* larger of the two numbers passed to it. If <xValue> and <xValue1> are
* date data types, the return value will be a date data
* type as well. It will be the later of the two dates passed to it.
* $EXAMPLES$
* ? MAX(214514214,6251242142)
* ? MAX(CTOD('11/11/2000'),CTOD('21/06/2014')
* </fixed>
* $STATUS$
* R
* $COMPLIANCE$
* This function is Ca-Clipper compliant.
* $PLATFORMS$
* All
* $FILES$
* Library is rtl
* $SEEALSO$
* Min()
* $END$
*/
/* $DOC$
* $FUNCNAME$
* MIN()
* $CATEGORY$
* Math
* $ONELINER$
* Determines the minumum of two numbers or dates.
* $SYNTAX$
* MIN(<xValue>,<xValue1>) --> <xMin>
* $ARGUMENTS$
* <xValue> Any date or numeric value.
*
* <xValue1> Any date or numeric value.
* $RETURNS$
* <xMin> The smaller numeric (or earlier date) value.
* $DESCRIPTION$
* This function returns the smaller of the two passed espressions.
* <xValue> and <xValue1> must be the same data type. If numeric, the
* smaller number is returned. If dates, the earlier date is returned.
* $EXAMPLES$
* ? MIN(214514214,6251242142)
* ? MIN(CTOD('11/11/2000'),CTOD('21/06/2014')
* </fixed>
* $STATUS$
* R
* $COMPLIANCE$
* This function is Ca-Clipper compliant.
* $PLATFORMS$
* All
* $FILES$
* Library is rtl
* $SEEALSO$
* MAX()
* $END$
*/
/* $DOC$
* $FUNCNAME$
* MOD()
* $CATEGORY$
* Math
* $ONELINER$
* Return the modulus of two numbers.
* $SYNTAX$
* MOD( <nNumber>,<nNumber1>) --> <nRemainder>
* $ARGUMENTS$
* <nNumber> Numerator in a divisional expression.
*
* <nNumber1> Denominator in a divisional expression.
* $RETURNS$
* <nRemainder> The remainder after the division operation.
* $DESCRIPTION$
* This functuion returns the remainder of one number divided by another.
* $EXAMPLES$
* ? MOD(12,8.521)
* ? Mod(12,0)
* ? Mod(62412.5142,4522114.12014)
* </fixed>
* $STATUS$
* R
* $COMPLIANCE$
* This Function is Ca-Clipper compliant.
* $PLATFORMS$
* All
* $FILES$
* Library is rtl
* $SEEALSO$
* %
* $END$
*/
/* $DOC$
* $FUNCNAME$
* SQRT()
* $CATEGORY$
* Math
* $ONELINER$
* Calculates the square root of a number.
* $SYNTAX$
* SQRT( <nNumber> ) --> <nSqrt>
* $ARGUMENTS$
* <nNumber> Any numeric value.
* $RETURNS$
* <nSqrt> The square root of <number>.
* $DESCRIPTION$
* This function returns the square root of <nNumber>. The precision of
* this evaluation is based solely on the settings of the SET DECIMAL TO
* command. Any negative number passed as <nNumber> will always return a 0.
* $EXAMPLES$
* SET Decimal to 5
* ? SQRT(632512.62541)
* ? SQRT(845414111.91440)
* $STATUS$
* R
* $COMPLIANCE$
* This function is CA-Clipper compliant.
* $PLATFORMS$
* All
* $FILES$
* Library is rtl
* $SEEALSO$
* ROUND()
* $END$
*/
/* $DOC$
* $FUNCNAME$
* ROUND()
* $CATEGORY$
* Math
* $ONELINER$
* Rounds off a numeric expression.
* $SYNTAX$
* ROUND( <nNumber>,<nPlace> ) --> <nResult>
* $ARGUMENTS$
* <nNumber> Any numeric value.
*
* <nPlace> The number of places to round to.
* $RETURNS$
* <nResult> The rounded number.
* $DESCRIPTION$
* This function rounds off the value of <nNumber> to the number of
* decimal places specified by <nPlace>. If the value of <nPlace> is a
* negative number, the function will attempt to round <nNumber> in whole
* numbers. Numbers from 5 through 9 will be rounded up, all others will
* be rounded down.
* $EXAMPLES$
* ? ROUND(632512.62541,5)
* ? ROUND(845414111.91440,3)
* $STATUS$
* R
* $COMPLIANCE$
* This function is CA-Clipper compliant.
* $PLATFORMS$
* All
* $FILES$
* Library is rtl
* $SEEALSO$
* INT(),STR(),VAL(),SET FIXED
* $END$
*/