Reference
C Library
IOstream Library
Strings library
STL Containers
STL Algorithms
Miscellaneous
C Library
cassert (assert.h)
cctype (ctype.h)
cerrno (errno.h)
cfloat (float.h)
ciso646 (iso646.h)
climits (limits.h)
clocale (locale.h)
cmath (math.h)
csetjmp (setjmp.h)
csignal (signal.h)
cstdarg (stdarg.h)
cstddef (stddef.h)
cstdio (stdio.h)
cstdlib (stdlib.h)
cstring (string.h)
ctime (time.h)
cmath (math.h)
functions:
abs
acos
asin
atan
atan2
ceil
cos
cosh
exp
fabs
floor
fmod
frexp
ldexp
log
log10
modf
pow
sin
sinh
sqrt
tan
tanh
macro constants:
HUGE_VAL


floor

function
<cmath>
     double floor (      double x );
      float floor (       float x );
long double floor ( long double x );

Round down value

Returns the largest integral value that is not greater than x.

Parameters

x
Floating point value.

Return Value

The largest integral value not greater than x.

Portability

In C, only the double version of this function exists with this name.

Example

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/* floor example */
#include <stdio.h>
#include <math.h>
int main ()
{
  printf ("floor of 2.3 is %.1lf\n", floor (2.3) );
  printf ("floor of 3.8 is %.1lf\n", floor (3.8) );
  printf ("floor of -2.3 is %.1lf\n", floor (-2.3) );
  printf ("floor of -3.8 is %.1lf\n", floor (-3.8) );
  return 0;
}


Output:

floor of 2.3 is 2.0
floor of 3.8 is 3.0
floor of -2.3 is -3.0
floor of -3.8 is -4.0

See also

ceil Round up value (function)
fabs Compute absolute value (function)
modf Break into fractional and integral parts (function)