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diff --git a/man3/floor.3 b/man3/floor.3 new file mode 100644 index 0000000..6040607 --- /dev/null +++ b/man3/floor.3 @@ -0,0 +1,106 @@ +'\" t +.\" Copyright 2001 Andries Brouwer <aeb@cwi.nl>. +.\" and Copyright 2008, Linux Foundation, written by Michael Kerrisk +.\" <mtk.manpages@gmail.com> +.\" +.\" SPDX-License-Identifier: Linux-man-pages-copyleft +.\" +.TH floor 3 2023-07-20 "Linux man-pages 6.05.01" +.SH NAME +floor, floorf, floorl \- largest integral value not greater than argument +.SH LIBRARY +Math library +.RI ( libm ", " \-lm ) +.SH SYNOPSIS +.nf +.B #include <math.h> +.PP +.BI "double floor(double " x ); +.BI "float floorf(float " x ); +.BI "long double floorl(long double " x ); +.fi +.PP +.RS -4 +Feature Test Macro Requirements for glibc (see +.BR feature_test_macros (7)): +.RE +.PP +.BR floorf (), +.BR floorl (): +.nf + _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L + || /* Since glibc 2.19: */ _DEFAULT_SOURCE + || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE +.fi +.SH DESCRIPTION +These functions return the largest integral value that is not greater than +.IR x . +.PP +For example, +.I floor(0.5) +is 0.0, and +.I floor(\-0.5) +is \-1.0. +.SH RETURN VALUE +These functions return the floor of +.IR x . +.PP +If +.I x +is integral, +0, \-0, NaN, or an infinity, +.I x +itself is returned. +.SH ERRORS +No errors occur. +POSIX.1-2001 documents a range error for overflows, but see NOTES. +.SH ATTRIBUTES +For an explanation of the terms used in this section, see +.BR attributes (7). +.TS +allbox; +lbx lb lb +l l l. +Interface Attribute Value +T{ +.na +.nh +.BR floor (), +.BR floorf (), +.BR floorl () +T} Thread safety MT-Safe +.TE +.sp 1 +.SH STANDARDS +C11, POSIX.1-2008. +.SH HISTORY +C99, POSIX.1-2001. +.PP +The variant returning +.I double +also conforms to +SVr4, 4.3BSD, C89. +.PP +SUSv2 and POSIX.1-2001 contain text about overflow (which might set +.I errno +to +.BR ERANGE , +or raise an +.B FE_OVERFLOW +exception). +In practice, the result cannot overflow on any current machine, +so this error-handling stuff is just nonsense. +.\" The POSIX.1-2001 APPLICATION USAGE SECTION discusses this point. +(More precisely, overflow can happen only when the maximum value +of the exponent is smaller than the number of mantissa bits. +For the IEEE-754 standard 32-bit and 64-bit floating-point numbers +the maximum value of the exponent is 127 (respectively, 1023), +and the number of mantissa bits +including the implicit bit +is 24 (respectively, 53).) +.SH SEE ALSO +.BR ceil (3), +.BR lrint (3), +.BR nearbyint (3), +.BR rint (3), +.BR round (3), +.BR trunc (3) |