Oracle® C++ Call Interface Programmer's Guide 10g Release 1 (10.1) Part Number B10778-01 |
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The Number
class handles limited-precision signed base 10
numbers. A Number
guarantees 38
decimal digits of precision. All positive numbers in the range displayed here can be represented to a full 38
-digit precision:
10^-130
and
9.99999999999999999999999999999999999999*10^125
The range of representable negative numbers is symmetrical.
The number zero can be represented exactly. Also, Oracle numbers have representations for positive and negative infinity. These are generally used to indicate overflow.
The internal storage type is opaque and private. Scale is not preserved when Number
instances are created.
Number
does not support the concept of NaN and is not IEEE-754-85 compliant. Number
does support +Infinity and -Infinity.
Objects from the Number
class can be used as standalone class objects in client side numerical computations. They can also be used to fetch from and set to the database.
The following code example demonstrates a Number
column value being retrieved from the database, a bind using a Number
object, and a comparison using a standalone Number
object:
/* Create a connection */ Environment *env = Environment::createEnvironment(Environment::DEFAULT); Connection *conn = env->createConnection(user, passwd, db); /* Create a statement and associate a select clause with it */ string sqlStmt = "SELECT department_id FROM DEPARTMENTS"; Statement *stmt = conn->createStatement(sqlStmt); /* Execute the statement to get a result set */ ResultSet *rset = stmt->executeQuery(); while(rset->next()) { Number deptId = rset->getNumber(1); /* Display the department id with the format string 9,999 */ cout << "Department Id" << deptId.toText(env, "9,999"); /* Use the number obtained as a bind value in the following query */ stmt->setSQL("SELECT * FROM EMPLOYEES WHERE department_id = :x"); stmt->setNumber(1, deptId); ResultSet *rset2 = stmt->executeQuery(); . . } /* Using a Number object as a standalone and the operations on them */ /* Create a number to a double value */ double value = 2345.123; Number nu1 (value); /* Some common Number methods */ Number abs = nu1.abs(); /* absolute value */ Number sqrt = nu1.squareroot(); /* square root */ Environment *env = Environment::createEnvironment(); //create a null year-month interval IntervalYM ym if(ym.isNull()) cout << "\n ym is null"; //assign a non null value to ym IntervalYM anotherYM(env, "10-30"); ym = anotherYM; //now all operations are valid on ym... int yr = ym.getYear();
Table 10-28 Summary of Number Methods
Method | Summary |
---|---|
Number() |
Number class constructor. |
abs() |
Return the absolute value of the number. |
arcCos() |
Return the arcCosine of the number. |
arcSin() |
Return the arcSine of the number. |
arcTan() |
Return the arcTangent of the number. |
arcTan2() |
Return the arcTangent2 of the input number y and this number x . |
ceil() |
Return the smallest integral value not less than the value of the number. |
cos() |
Return the cosine of the number. |
exp() |
Return the natural exponent of the number. |
floor() |
Return the largest integral value not greater than the value of the number. |
fromBytes() |
Return a Number derived from a Bytes object. |
fromText() |
Return a Number from a given number string, format string and nls parameters specified. |
hypCos() |
Return the hyperbolic cosine of the number. |
hypSin() |
Return the hyperbolic sine of the number. |
hypTan() |
Return the hyperbolic tangent of the number. |
intPower() |
Return the number raised to the integer value specified. |
isNull() |
Check if Number is NULL . |
ln() |
Return the natural logarithm of the number. |
log() |
Return the logarithm of the number to the base value specified. |
operator++() |
Increment the number by 1. |
-- |
Decrement the number by 1. |
operator*() |
Return the product of two Number s. |
operator/() |
Return the quotient of two Number s. |
operator%() |
Return the modulo of two Number s. |
operator+() |
Return the sum of two Number s. |
operator-() |
Return the negated value of Number. |
operator-() |
Return the difference between two Number s. |
operator<() |
Check if a number is less than an other number. |
operator<=() |
Check if a number is less than or equal to an other number. |
operator>() |
Check if a number is greater than an other number. |
operator>=() |
Check if a number is greater than or equal to an other number. |
operator=() |
Assign one number to another. |
operator==() |
Check if two numbers are equal. |
operator!=() |
Check if two numbers are not equal. |
operator*=() |
Multiplication assignment. |
operator/=() |
Division assignment. |
operator%=() |
Modulo assignment. |
operator+=() |
Addition assignment. |
-= |
Subtraction assignment. |
operator char() |
Return Number converted to native char. |
operator signed char() |
Return Number converted to native signed char. |
operator double() |
Return Number converted to a native double. |
operator float() |
Return Number converted to a native float. |
operator int() |
Return Number converted to native integer. |
operator long() |
Return Number converted to native long. |
operator long double() |
Return Number converted to a native long double. |
operator short() |
Return Number converted to native short integer. |
operator unsigned char() |
Return Number converted to an unsigned native char. |
operator unsigned int() |
Return Number converted to an unsigned native integer. |
operator unsigned long() |
Return Number converted to an unsigned native long. |
operator unsigned short() |
Return Number converted to an unsigned native short integer. |
power() |
Return Number raised to the power of another number specified. |
prec() |
Return Number rounded to digits of precision specified. |
round() |
Return Number rounded to decimal place specified. Negative values are allowed. |
setNull() |
Set Number to NULL . |
shift() |
Return a Number that is equivalent to the passed value * 10^n , where n may be positive or negative. |
sign() |
Return the sign of the value of the passed value: -1 for the passed value < 0, 0 for the passed value == 0, and 1 for the passed value > 0. |
sin() |
Return sine of the number. |
squareroot() |
Return the square root of the number. |
tan() |
Returns tangent of the number. |
toBytes() |
Return a Bytes object representing the Number . |
toText() |
Return the number as a string formatted based on the format and nls parameters. |
trunc() |
Return a Number with the value truncated at n decimal place(s). Negative values are allowed. |
Number
class constructor.
Syntax | Description |
---|---|
Number(); |
Default constructor. |
Number( const Number &val); |
Creates a copy of a Number . |
Number( long double &val); |
Translates a native long double into a Number . The Number is created using the precision of the platform-specific constant LDBL_DIG . |
Number( double val); |
Translates a native double into a Number . The Number is created using the precision of the platform-specific constant DBL_DIG . |
Number( float val); |
Translates a native float into a Number . The Number is created using the precision of the platform-specific constant FLT_DIG . |
Number( long val); |
Translates a native long into a Number . |
Number( int val); |
Translates a native int into a Number . |
Number( shot val); |
Translates a native short into a Number . |
Number( char val); |
Translates a native char into a Number . |
Number( signed char val); |
Translates a native signed char into a Number . |
Number( unsigned long val); |
Translates an native unsigned long into a Number . |
Number( unsigned int val); |
Translates a native unsigned int into a Number . |
Number( unsigned short val); |
Translates a native unsigned short into a Number . |
Number( unsigned char val); |
Translates the unsigned character array into a Number . |
Parameter | Description |
---|---|
val |
The value assigned to the Number object. |
This method returns the absolute value of the Number
object.
const Number abs() const;
This method returns the arccosine of the Number
object.
const Numberconst Number arcCos() const;
This method returns the arcsine of the Number
object.
const Number arcSin() const;
This method returns the arctangent of the Number
object.
const Number arcTan() const;
This method returns the arctangent of the Number
object with the parameter specified. It returns atan2 (val, x) where val is the parameter specified and x is the current number object.
const Number arcTan2( const Number &val) const;
Parameter | Description |
---|---|
val |
Number parameter val to the arcTangent function atan2(val,x) . |
This method returns the smallest integer that is greater than or equal to the Number
object.
const Number ceil() const;
This method returns the cosine of the Number
object.
const Number cos() const;
This method returns the natural exponential of the Number
object.
const Number exp() const;
This method returns the largest integer that is less than or equal to the Number
object.
const Number floor() const;
This method returns a Number
object represented by the byte string specified.
void fromBytes( const Bytes &str);
Parameter | Description |
---|---|
str |
A byte string. |
Set Number
object to value represented by a string
or UString
.
The value is interpreted based on the fmt
and nlsParam
parameters. In cases where nlsParam
is not passed, the Globalization Support settings of the envp
parameter are used.
Syntax | Description |
---|---|
void fromText( const Environment *envp, const string &numstr, const string &fmt, const string &nlsParam = ""); |
Set Number object to value represented by a string . |
void fromText( const Environment *envp, const UString &numstr, const UString &fmt, const UString &nlsParam); |
Set Number object to value represented by a UString . |
Parameter | Description |
---|---|
envp |
The OCCI environment. |
number |
The number string to be converted to a Number object. |
fmt |
The format string. |
nlsParam |
The nls parameters string. If nlsParam is specified, this determines the nls parameters to be used for the conversion. If nlsParam is not specified, the nls parameters are picked up from envp . |
This method returns the hypercosine of the Number
object.
const Number hypCos() const;
This method returns the hypersine of the Number
object.
const Number hypSin() const;
This method returns the hypertangent of the Number
object.
const Number hypTan() const;
This method returns a Number
whose value is the number object raised to the power of the value specified.
const Number intPower( int val) const;
Parameter | Description |
---|---|
val |
Power to which the number is raised. |
This method tests whether the Number
object is NULL
. If the Number
object is NULL
, then TRUE
is returned; otherwise, FALSE
is returned.
bool isNull() const;
This method returns the natural logarithm of the Number
object.
const Number ln() const;
This method returns the logarithm of the Number
object with the base provided by the parameter specified.
const Number log( const Number &val) const;
Parameter | Description |
---|---|
val |
The base to be used in the logarithm calculation. |
++
()Unary operator++()
. This method returns the Number
object incremented by 1
. This is a prefix operator.
Number& operator++();
Unary operator++().
This method returns the Number
object incremented by the integer specified. This is a postfix operator.
const Number operator++( int incr);
Parameter | Description |
---|---|
incr |
The number by which the Number object is incremented. |
--
()Unary operator--()
. This method returns the Number
object decremented by 1
. This is a prefix operator.
Number& operator--();
--
()Unary operator--()
. This method returns the Number
object decremented by the integer specified. This is a postfix operator.
const Number operator--( int decr);
Parameter | Description |
---|---|
decr |
The number by which the Number object is decremented. |
This method returns the product of the parameters specified.
Number operator*( const Number &first,
const Number &second);
Parameter | Description |
---|---|
first |
First multiplicand. |
second |
Second multiplicand. |
This method returns the quotient of the parameters specified.
Number operator/( const Number ÷nd, const Number &divisor);
Parameter | Description |
---|---|
dividend |
The number to be divided. |
divizor |
The number by which to divide. |
This method returns the remainder of the division of the parameters specified.
Number operator%( const Number ÷nd, const Number ÷r);
Parameter | Description |
---|---|
dividend |
The number to be divided. |
divizor |
The number by which to divide. |
This method returns the sum of the parameters specified.
Number operator+( const Number &first, const Number &second);
Parameter | Description |
---|---|
first |
First number to be added. |
second |
Second number to be added. |
Unary operator-()
. This method returns the negated value of the Number
object.
const Number operator-();
This method returns the difference between the parameters specified.
Number operator-( const Number &subtrahend, const Number &subtractor);
Parameter | Description |
---|---|
subtrahend |
The number to be reduced. |
subtractor |
The number to be subtracted. |
This method checks whether the first parameter specified is less than the second parameter specified. If the first parameter is less than the second parameter, then TRUE
is returned; otherwise, FALSE
is returned. If either parameter is equal to infinity, then FALSE
is returned.
bool operator<( const Number &first, const Number &second);
Parameter | Description |
---|---|
first |
First number to be compared. |
second |
Second number to be compared. |
This method checks whether the first parameter specified is less than or equal to the second parameter specified. If the first parameter is less than or equal to the second parameter, then TRUE
is returned; otherwise, FALSE
is returned. If either parameter
is equal to infinity, then FALSE
is returned.
bool operator<=( const Number &first, const Number &second);
Parameter | Description |
---|---|
first |
First number to be compared. |
second |
Second number to be compared. |
This method checks whether the first parameter specified is greater than the second parameter specified. If the first parameter is greater than the second parameter, then TRUE
is returned; otherwise, FALSE
is returned. If either parameter is equal to infinity, then FALSE
is returned.
bool operator>( const Number &first, const Number &second);
Parameter | Description |
---|---|
first |
First number to be compared. |
second |
Second number to be compared. |
This method checks whether the first parameter specified is greater than or equal to the second parameter specified. If the first parameter is greater than or equal to the second parameter, then TRUE
is returned; otherwise, FALSE
is returned. If either parameter is equal to infinity, then FALSE
is returned.
bool operator>=( const Number &first, const Number &second);
Parameter | Description |
---|---|
first |
First number to be compared. |
second |
Second number to be compared. |
This method checks whether the parameters specified are equal. If the parameters are equal, then TRUE
is returned; otherwise, FALSE
is returned. If either parameter is equal to +infinity or -infinity, then FALSE
is returned.
bool operator==( const Number &first, const Number &second);
Parameter | Description |
---|---|
first |
First number to be compared. |
second |
Second number to be compared. |
This method checks whether the first parameter specified is equal to the second parameter specified. If the parameters are not equal, TRUE
is returned; otherwise, FALSE
is returned.
bool operator!=( const Number &first, const Number &second);
Parameter | Description |
---|---|
first |
First number to be compared. |
second |
Second number to be compared. |
This method assigns the value of the parameter specified to the Number
object.
Number& operator=( const Number &num);
Parameter | Description |
---|---|
num |
A parameter of type Number . |
This method multiplies the Number
object by the parameter specified, and assigns the product to the Number
object.
Number& operator*=( const Number &num);
Parameter | Description |
---|---|
num |
A parameter of type Number . |
This method divides the Number
object by the parameter specified, and assigns the quotient to the Number
object.
Number& operator/=( const Number &num);
Parameter | Description |
---|---|
num |
A parameter of type Number . |
This method divides the Number
object by the parameter specified, and assigns the remainder to the Number
object.
Number& operator%=( const Number &num);
Parameter | Description |
---|---|
num |
A parameter of type Number . |
This method adds the Number object and the parameter specified, and assigns the sum to the Number
object.
Number& operator+=( const Number &num);
Parameter | Description |
---|---|
num |
A parameter of type Number . |
-=
()This method subtracts the parameter specified from the Number
object, and assigns the difference to the Number
object.
Number& operator-=( const Number &num);
Parameter | Description |
---|---|
num |
A parameter of type Number . |
This method returns the value of the Number object converted to a native char
.
operator char() const;
This method returns the value of the Number object converted to a native signed char
.
operator signed char() const;
This method returns the value of the Number
object converted to a native double
.
operator double() const;
This method returns the value of the Number
object converted to a native float
.
operator float() const;
This method returns the value of the Number
object converted to a native int
.
operator int() const;
This method returns the value of the Number
object converted to a native long
.
operator long() const;
This method returns the value of the Number
object converted to a native long double
.
operator long double() const;
This method returns the value of the Number
object converted to a native short
integer.
operator short() const;
This method returns the value of the Number
object converted to a native unsigned char
.
operator unsigned char() const;
This method returns the value of the Number
object converted to a native unsigned int
.
operator unsigned int() const;
This method returns the value of the Number
object converted to a native unsigned long
.
operator unsigned long() const;
This method returns the value of the Number
object converted to a native unsigned short
integer.
operator unsigned short() const;
This method returns the value of the Number
object raised to the power of the value provided by the parameter specified.
const Number power( const Number &val) const;
Parameter | Description |
---|---|
val |
The power to which the number has to be raised. |
This method returns the value of the Number
object rounded to the digits of precision provided by the parameter specified.
const Number prec( int digits) const;
Parameter | Description |
---|---|
digits |
The number of digits of precision. |
This method returns the value of the Number
object rounded to the decimal place provided by the parameter specified.
const Number round( int decPlace) const;
Parameter | Description |
---|---|
decPlace |
The number of digits to the right of the decimal point. |
This method sets the value of the Number
object to NULL
.
void setNull();
This method returns the Number
object multiplied by 10 to the power provided by the parameter specified.
const Number shift( int val) const;
Parameter | Description |
---|---|
val |
An integer value. |
This method returns the sign of the value of the Number
object. If the Number
object is negative, then create a Date
object using integer parameters is returned. If the Number
object is equal to 0
, then create a Date
object using integer parameters is returned. If the Number
object is positive, then 1
is returned.
const int sign() const;
This method returns the sin of the Number
object.
const Number sin();
This method returns the square root of the Number
object.
const Number squareroot() const;
This method returns the tangent of the Number
object.
const Number tan() const;
This method converts the Number
object into a Bytes
object. The bytes representation is assumed to be in length excluded format, that is, the Byte.length()
method gives the length of valid bytes and the 0
th byte is the exponent byte.
Bytes toBytes() const;
Convert the Number
object to a formatted string
or UString
based on the parameters specified.
Syntax | Description |
---|---|
string toText( const Environment *envp, const string &fmt, const string &nlsParam = "") const; |
Convert the Number object to a formatted string based on the parameters specified. |
UString toText( const Environment *envp, const UString &fmt, const UString &nlsParam) const; |
Convert the Number object to a UString based on the parameters specified. |
Parameter | Description |
---|---|
envp |
The OCCI environment. |
fmt |
The format string. |
nlsParam |
The nls parameters string. If nlsParam is specified, this determines the nls parameters to be used for the conversion. If nlsParam is not specified, the nls parameters are picked up from envp . |
This method returns the Number
object truncated at the number of decimal places provided by the parameter specified.
const Number trunc( int decPlace) const;
Parameter | Description |
---|---|
decPlace |
The number of places to the right of the decimal place at which the value is to be truncated. |