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				.Dd July 8, 2018
				.Dt Q_SIGNED 3
				.Os
				.Sh NAME
				.Nm Q_SIGNED ,
				.Nm Q_LTZ ,
				.Nm Q_PRECEQ ,
				.Nm Q_QLTQ ,
				.Nm Q_QLEQ ,
				.Nm Q_QGTQ ,
				.Nm Q_QGEQ ,
				.Nm Q_QEQ ,
				.Nm Q_QNEQ ,
				.Nm Q_OFLOW ,
				.Nm Q_RELPREC
				.Nd fixed-point math comparison and logic functions
				.Sh SYNOPSIS
				.In sys/qmath.h
				.Ft bool
				.Fn Q_SIGNED "NTYPE n"
				.Ft bool
				.Fn Q_LTZ "NTYPE n"
				.Ft bool
				.Fn Q_PRECEQ "QTYPE a" "QTYPE b"
				.Ft bool
				.Fn Q_QLTQ "QTYPE a" "QTYPE b"
				.Ft bool
				.Fn Q_QLEQ "QTYPE a" "QTYPE b"
				.Ft bool
				.Fn Q_QGTQ "QTYPE a" "QTYPE b"
				.Ft bool
				.Fn Q_QGEQ "QTYPE a" "QTYPE b"
				.Ft bool
				.Fn Q_QEQ "QTYPE a" "QTYPE b"
				.Ft bool
				.Fn Q_QNEQ "QTYPE a" "QTYPE b"
				.Ft bool
				.Fn Q_OFLOW "QTYPE q" "ITYPE iv"
				.Ft int
				.Fn Q_RELPREC "QTYPE a" "QTYPE b"
				.Sh DESCRIPTION
				.Fn Q_SIGNED
				returns
				.Ft true
				if the numeric data type passed in as
				.Fa n
				is signed, or
				.Ft false
				otherwise.
				.Pp
				.Fn Q_LTZ
				returns
				.Ft true
				if the numeric value
				passed in as
				.Fa n
				is negative
				.Pq requires types which use the MSB as the sign bit ,
				or
				.Ft false
				otherwise.
				.Pp
				.Fn Q_PRECEQ
				returns
				.Ft true
				if the number of
				.Fa a
				and
				.Fa b
				fractional bits is the same,
				.Ft false
				otherwise.
				.Pp
				The
				.Fn Q_QLTQ ,
				.Fn Q_QLEQ ,
				.Fn Q_QGTQ ,
				.Fn Q_QGEQ ,
				.Fn Q_QEQ
				and
				.Fn Q_QNEQ
				functions compare two Q numbers, returning
				.Ft true
				if
				.Fa a
				is less than, less than or equal to, greater than, greater than or equal to,
				equal to, or not equal to
				.Fa b
				respectively, or
				.Ft false
				otherwise.
				The integral and fractional values are used to perform the comparison, without
				explicit concern for the underlying number of integer versus fractional bits.
				.Pp
				.Fn Q_OFLOW
				returns
				.Ft true
				if integer value
				.Fa iv
				cannot be stored in
				.Fa q
				without truncation, or false otherwise.
				.Pp
				.Fn Q_RELPREC
				returns the relative precision of
				.Fa a
				versus
				.Fa b .
				In terms of
				.Em Qm.n
				notation, this function returns the difference between the
				.Em n
				values of
				.Fa a
				and
				.Fa b .
				For example, a return value of +4 means that
				.Fa a
				has an additional 4 bits of fractional precision compared to
				.Fa b .

				sefUnsubmitted Done Inline Actions Missing .Pp? sef: Missing .Pp?
				All of those functions operate on
				the following data types:
				.Vt s8q_t ,
				.Vt u8q_t ,
				.Vt s16q_t ,
				.Vt u16q_t ,
				.Vt s32q_t ,
				.Vt u32q_t ,
				.Vt s64q_t ,
				and
				.Vt u64q_t ,
				which are referred to generically as
				.Fa QTYPE .
				The
				.Fa ITYPE
				refers to the
				.Xr stdint 7
				integer types.
				.Fa NTYPE
				is used to refer to any numeric type and is therefore a superset of
				.Fa QTYPE
				and
				.Fa ITYPE .
				.Pp
				For more details, see
				.Xr qmath 3 .
				.Sh RETURN VALUES
				The
				.Fn Q_SIGNED ,
				.Fn Q_LTZ ,
				.Fn Q_PRECEQ ,
				.Fn Q_QLTQ ,
				.Fn Q_QLEQ ,
				.Fn Q_QGTQ ,
				.Fn Q_QGEQ ,
				.Fn Q_QEQ ,
				.Fn Q_QNEQ
				and
				.Fn Q_OFLOW
				functions return expressions that evaluate to boolean
				.Vt true
				or
				.Vt false .
				.Pp
				.Fn Q_RELPREC
				returns the relative precision difference as a signed integer.
				.Sh SEE ALSO
				.Xr errno 2 ,
				.Xr qmath 3 ,
				.Xr stdint 7
				.Sh HISTORY
				The
				.Xr qmath 3
				functions first appeared in
				.Fx 13.0 .
				.Sh AUTHORS
				.An -nosplit
				The
				.Xr qmath 3
				functions and this manual page were written by
				.An Lawrence Stewart Aq Mt lstewart@FreeBSD.org
				and sponsored by Netflix, Inc.