$NCONVERT (ObjectScript)
Synopsis
$NCONVERT(n,format,endian)
$NC(n,format,endian)
Arguments
| Argument | Description |
|---|---|
| n | Any number, which can be specified as a value, a variable, or an expression. Additional limitations on valid values are imposed by the format selected. |
| format | One of the following format codes, specified as a quoted string: S1, S2, S4, S8, U1, U2, U4, F4, or F8. |
| endian | Optional — A boolean value, where 0 = little-endian and 1 = big-endian. The default is 0. |
Description
$NCONVERT uses the specified format to convert the number n to an encoded string of 8-bit characters. The values of these characters are in the range $CHAR(0) through $CHAR(255).
The following are the supported format codes:
| Code | Description |
|---|---|
| S1 | Signed integer encoded into a string of one 8-bit byte. The value must be in the range -128 through 127, inclusive. |
| S2 | Signed integer encoded into a string of two 8-bit bytes. The value must be in the range -32768 through 32767, inclusive. |
| S4 | Signed integer encoded into a string of four 8-bit bytes. The value must be in the range -2147483648 through 2147483647, inclusive. |
| S8 | Signed integer encoded into a string of eight 8-bit bytes. The value must be in the range -9223372036854775808 through 9223372036854775807, inclusive. |
| U1 | Unsigned integer encoded into a string of one 8-bit byte. The maximum value is 255. |
| U2 | Unsigned integer encoded into a string of two 8-bit bytes. The maximum value is 65535. |
| U4 | Unsigned integer encoded into a string of four 8-bit bytes. The maximum value is 4294967295. |
| F4 | IEEE floating point number encoded into a string of four 8-bit bytes. |
| F8 | IEEE floating point number encoded into a string of eight 8-bit bytes. |
Values beyond the range of format limits result in a <VALUE OUT OF RANGE> error. Specifying a negative number for an Unsigned format results in a <VALUE OUT OF RANGE> error. If n is a non-numeric value (contains any non-numeric characters) InterSystems IRIS performs conversion of a string to a numeric value. A string beginning with a non-numeric character is converted to 0.
InterSystems IRIS rounds a fractional number to an integer value for all formats except F4 and F8.
You can use the IsBigEndian()Opens in a new tab class method to determine which bit ordering is used on your operating system platform: 1=big-endian bit order; 0=little-endian bit order.
WRITE $SYSTEM.Version.IsBigEndian()$SCONVERT provides the inverse of the $NCONVERT operation.
Examples
The following example converts a series of unsigned numbers to two-byte encoded values:
FOR x=250:1:260 {
ZZDUMP $NCONVERT(x,"U2") }
QUITThe following example performs the same operation in big-endian order:
FOR x=250:1:260 {
ZZDUMP $NCONVERT(x,"U2",1) }
QUITSee Also
-
$SCONVERT function
