Class: Float

Inherits:
Numeric show all
Includes:
Precision
Defined in:
numeric.c

Overview

Float objects represent real numbers using the native architecture???s double-precision floating point representation.

Constant Summary collapse

ROUNDS = 
INT2FIX(FLT_ROUNDS)
RADIX = 
INT2FIX(FLT_RADIX)
MANT_DIG = 
INT2FIX(DBL_MANT_DIG)
DIG = 
INT2FIX(DBL_DIG)
MIN_EXP = 
INT2FIX(DBL_MIN_EXP)
MAX_EXP = 
INT2FIX(DBL_MAX_EXP)
MIN_10_EXP = 
INT2FIX(DBL_MIN_10_EXP)
MAX_10_EXP = 
INT2FIX(DBL_MAX_10_EXP)
MIN = 
rb_float_new(DBL_MIN)
MAX = 
rb_float_new(DBL_MAX)
EPSILON = 
rb_float_new(DBL_EPSILON)

Class Method Summary collapse

Instance Method Summary collapse

Methods included from Precision

included, #prec, #prec_f, #prec_i

Methods inherited from Numeric

#+@, #div, #fdiv, #initialize_copy, #integer?, #nonzero?, #quo, #remainder, #singleton_method_added, #step

Methods included from Comparable

#between?

Class Method Details

.induced_from(obj) ⇒ Float

Convert obj to a float.

Returns:




# File 'numeric.c'

/*
 * call-seq:
 *   Float.induced_from(obj)    =>  float
 *
 * Convert <code>obj</code> to a float.
 */

static VALUE
rb_flo_induced_from(klass, x)
    VALUE klass, x;
{
    switch (TYPE(x)) {
    case T_FIXNUM:
    case T_BIGNUM:
       return rb_funcall(x, rb_intern("to_f"), 0);
    case T_FLOAT:
       return x;
    default:
       rb_raise(rb_eTypeError, "failed to convert %s into Float",
                rb_obj_classname(x));
    }
}

Instance Method Details

#%(other) ⇒ Float #modulo(other) ⇒ Float

Return the modulo after division of flt by other.

6543.21.modulo(137)      #=> 104.21
6543.21.modulo(137.24)   #=> 92.9299999999996

Overloads:




# File 'numeric.c'

/*
 *  call-seq:
 *     flt % other         => float
 *     flt.modulo(other)   => float
 *
 *  Return the modulo after division of <code>flt</code> by <code>other</code>.
 *
 *     6543.21.modulo(137)      #=> 104.21
 *     6543.21.modulo(137.24)   #=> 92.9299999999996
 */

static VALUE
flo_mod(x, y)
    VALUE x, y;
{
    double fy, mod;

    switch (TYPE(y)) {
      case T_FIXNUM:
    fy = (double)FIX2LONG(y);
    break;
      case T_BIGNUM:
    fy = rb_big2dbl(y);
    break;
      case T_FLOAT:
    fy = RFLOAT(y)->value;
    break;
      default:
    return rb_num_coerce_bin(x, y);
    }
    flodivmod(RFLOAT(x)->value, fy, 0, &mod);
    return rb_float_new(mod);
}

#*(other) ⇒ Float

Returns a new float which is the product of float and other.

Returns:




# File 'numeric.c'

/*
 * call-seq:
 *   float * other   => float
 *
 * Returns a new float which is the product of <code>float</code>
 * and <code>other</code>.
 */

static VALUE
flo_mul(x, y)
    VALUE x, y;
{
    switch (TYPE(y)) {
      case T_FIXNUM:
    return rb_float_new(RFLOAT(x)->value * (double)FIX2LONG(y));
      case T_BIGNUM:
    return rb_float_new(RFLOAT(x)->value * rb_big2dbl(y));
      case T_FLOAT:
    return rb_float_new(RFLOAT(x)->value * RFLOAT(y)->value);
      default:
    return rb_num_coerce_bin(x, y);
    }
}

#**(other) ⇒ Float

Raises float the other power.

Returns:




# File 'numeric.c'

/*
 * call-seq:
 *
 *  flt ** other   => float
 *
 * Raises <code>float</code> the <code>other</code> power.
 */

static VALUE
flo_pow(x, y)
    VALUE x, y;
{
    switch (TYPE(y)) {
      case T_FIXNUM:
        return rb_float_new(pow(RFLOAT(x)->value, (double)FIX2LONG(y)));
      case T_BIGNUM:
    return rb_float_new(pow(RFLOAT(x)->value, rb_big2dbl(y)));
      case T_FLOAT:
        return rb_float_new(pow(RFLOAT(x)->value, RFLOAT(y)->value));
      default:
        return rb_num_coerce_bin(x, y);
    }
}

#+(other) ⇒ Float

Returns a new float which is the sum of float and other.

Returns:




# File 'numeric.c'

/*
 * call-seq:
 *   float + other   => float
 *
 * Returns a new float which is the sum of <code>float</code>
 * and <code>other</code>.
 */

static VALUE
flo_plus(x, y)
    VALUE x, y;
{
    switch (TYPE(y)) {
      case T_FIXNUM:
    return rb_float_new(RFLOAT(x)->value + (double)FIX2LONG(y));
      case T_BIGNUM:
    return rb_float_new(RFLOAT(x)->value + rb_big2dbl(y));
      case T_FLOAT:
    return rb_float_new(RFLOAT(x)->value + RFLOAT(y)->value);
      default:
    return rb_num_coerce_bin(x, y);
    }
}

#+(other) ⇒ Float

Returns a new float which is the difference of float and other.

Returns:




# File 'numeric.c'

/*
 * call-seq:
 *   float + other   => float
 *
 * Returns a new float which is the difference of <code>float</code>
 * and <code>other</code>.
 */

static VALUE
flo_minus(x, y)
    VALUE x, y;
{
    switch (TYPE(y)) {
      case T_FIXNUM:
    return rb_float_new(RFLOAT(x)->value - (double)FIX2LONG(y));
      case T_BIGNUM:
    return rb_float_new(RFLOAT(x)->value - rb_big2dbl(y));
      case T_FLOAT:
    return rb_float_new(RFLOAT(x)->value - RFLOAT(y)->value);
      default:
    return rb_num_coerce_bin(x, y);
    }
}

#- ⇒ Float

Returns float, negated.

Returns:




# File 'numeric.c'

/*
 * call-seq:
 *    -float   => float
 *
 * Returns float, negated.
 */

static VALUE
flo_uminus(flt)
    VALUE flt;
{
    return rb_float_new(-RFLOAT(flt)->value);
}

#/(other) ⇒ Float

Returns a new float which is the result of dividing float by other.

Returns:




# File 'numeric.c'

/*
 * call-seq:
 *   float / other   => float
 *
 * Returns a new float which is the result of dividing
 * <code>float</code> by <code>other</code>.
 */

static VALUE
flo_div(x, y)
    VALUE x, y;
{
    long f_y;
    double d;

    switch (TYPE(y)) {
      case T_FIXNUM:
    f_y = FIX2LONG(y);
    return rb_float_new(RFLOAT(x)->value / (double)f_y);
      case T_BIGNUM:
    d = rb_big2dbl(y);
    return rb_float_new(RFLOAT(x)->value / d);
      case T_FLOAT:
    return rb_float_new(RFLOAT(x)->value / RFLOAT(y)->value);
      default:
    return rb_num_coerce_bin(x, y);
    }
}

#<(other) ⇒ Boolean

true if flt is less than other.

Returns:

  • (Boolean) 



# File 'numeric.c'

/*
 * call-seq:
 *   flt < other    =>  true or false
 *
 * <code>true</code> if <code>flt</code> is less than <code>other</code>.
 */

static VALUE
flo_lt(x, y)
    VALUE x, y;
{
    double a, b;

    a = RFLOAT(x)->value;
    switch (TYPE(y)) {
      case T_FIXNUM:
    b = (double)FIX2LONG(y);
    break;

      case T_BIGNUM:
    b = rb_big2dbl(y);
    break;

      case T_FLOAT:
    b = RFLOAT(y)->value;
    if (isnan(b)) return Qfalse;
    break;

      default:
    return rb_num_coerce_relop(x, y);
    }
    if (isnan(a)) return Qfalse;
    return (a < b)?Qtrue:Qfalse;
}

#<=(other) ⇒ Boolean

true if flt is less than or equal to other.

Returns:

  • (Boolean) 



# File 'numeric.c'

/*
 * call-seq:
 *   flt <= other    =>  true or false
 *
 * <code>true</code> if <code>flt</code> is less than
 * or equal to <code>other</code>.
 */

static VALUE
flo_le(x, y)
    VALUE x, y;
{
    double a, b;

    a = RFLOAT(x)->value;
    switch (TYPE(y)) {
      case T_FIXNUM:
    b = (double)FIX2LONG(y);
    break;

      case T_BIGNUM:
    b = rb_big2dbl(y);
    break;

      case T_FLOAT:
    b = RFLOAT(y)->value;
    if (isnan(b)) return Qfalse;
    break;

      default:
    return rb_num_coerce_relop(x, y);
    }
    if (isnan(a)) return Qfalse;
    return (a <= b)?Qtrue:Qfalse;
}

#<=>(numeric) ⇒ -1, ...

Returns -1, 0, or +1 depending on whether flt is less than, equal to, or greater than numeric. This is the basis for the tests in Comparable.

Returns:

  • (-1, 0, +1) 



# File 'numeric.c'

/*
 *  call-seq:
 *     flt <=> numeric   => -1, 0, +1
 *
 *  Returns -1, 0, or +1 depending on whether <i>flt</i> is less than,
 *  equal to, or greater than <i>numeric</i>. This is the basis for the
 *  tests in <code>Comparable</code>.
 */

static VALUE
flo_cmp(x, y)
    VALUE x, y;
{
    double a, b;

    a = RFLOAT(x)->value;
    switch (TYPE(y)) {
      case T_FIXNUM:
    b = (double)FIX2LONG(y);
    break;

      case T_BIGNUM:
    b = rb_big2dbl(y);
    break;

      case T_FLOAT:
    b = RFLOAT(y)->value;
    break;

      default:
    return rb_num_coerce_cmp(x, y);
    }
    return rb_dbl_cmp(a, b);
}

#==(obj) ⇒ Boolean

Returns true only if obj has the same value as flt. Contrast this with Float#eql?, which requires obj to be a Float.

1.0 == 1   #=> true

Returns:

  • (Boolean) 



# File 'numeric.c'

/*
 *  call-seq:
 *     flt == obj   => true or false
 *
 *  Returns <code>true</code> only if <i>obj</i> has the same value
 *  as <i>flt</i>. Contrast this with <code>Float#eql?</code>, which
 *  requires <i>obj</i> to be a <code>Float</code>.
 *
 *     1.0 == 1   #=> true
 *
 */

static VALUE
flo_eq(x, y)
    VALUE x, y;
{
    volatile double a, b;

    switch (TYPE(y)) {
      case T_FIXNUM:
    b = FIX2LONG(y);
    break;
      case T_BIGNUM:
    b = rb_big2dbl(y);
    break;
      case T_FLOAT:
    b = RFLOAT(y)->value;
    if (isnan(b)) return Qfalse;
    break;
      default:
    return num_equal(x, y);
    }
    a = RFLOAT(x)->value;
    if (isnan(a)) return Qfalse;
    return (a == b)?Qtrue:Qfalse;
}

#>(other) ⇒ Boolean

true if flt is greater than other.

Returns:

  • (Boolean) 



# File 'numeric.c'

/*
 * call-seq:
 *   flt > other    =>  true or false
 *
 * <code>true</code> if <code>flt</code> is greater than <code>other</code>.
 */

static VALUE
flo_gt(x, y)
    VALUE x, y;
{
    double a, b;

    a = RFLOAT(x)->value;
    switch (TYPE(y)) {
      case T_FIXNUM:
    b = (double)FIX2LONG(y);
    break;

      case T_BIGNUM:
    b = rb_big2dbl(y);
    break;

      case T_FLOAT:
    b = RFLOAT(y)->value;
    if (isnan(b)) return Qfalse;
    break;

      default:
    return rb_num_coerce_relop(x, y);
    }
    if (isnan(a)) return Qfalse;
    return (a > b)?Qtrue:Qfalse;
}

#>=(other) ⇒ Boolean

true if flt is greater than or equal to other.

Returns:

  • (Boolean) 



# File 'numeric.c'

/*
 * call-seq:
 *   flt >= other    =>  true or false
 *
 * <code>true</code> if <code>flt</code> is greater than
 * or equal to <code>other</code>.
 */

static VALUE
flo_ge(x, y)
    VALUE x, y;
{
    double a, b;

    a = RFLOAT(x)->value;
    switch (TYPE(y)) {
      case T_FIXNUM:
    b = (double)FIX2LONG(y);
    break;

      case T_BIGNUM:
    b = rb_big2dbl(y);
    break;

      case T_FLOAT:
    b = RFLOAT(y)->value;
    if (isnan(b)) return Qfalse;
    break;

      default:
    return rb_num_coerce_relop(x, y);
    }
    if (isnan(a)) return Qfalse;
    return (a >= b)?Qtrue:Qfalse;
}

#abs ⇒ Float

Returns the absolute value of flt.

(-34.56).abs   #=> 34.56
-34.56.abs     #=> 34.56

Returns:




# File 'numeric.c'

/*
 *  call-seq:
 *     flt.abs    => float
 *
 *  Returns the absolute value of <i>flt</i>.
 *
 *     (-34.56).abs   #=> 34.56
 *     -34.56.abs     #=> 34.56
 *
 */

static VALUE
flo_abs(flt)
    VALUE flt;
{
    double val = fabs(RFLOAT(flt)->value);
    return rb_float_new(val);
}

#ceil ⇒ Integer

Returns the smallest Integer greater than or equal to flt.

1.2.ceil      #=> 2
2.0.ceil      #=> 2
(-1.2).ceil   #=> -1
(-2.0).ceil   #=> -2

Returns:




# File 'numeric.c'

/*
 *  call-seq:
 *     flt.ceil    => integer
 *
 *  Returns the smallest <code>Integer</code> greater than or equal to
 *  <i>flt</i>.
 *
 *     1.2.ceil      #=> 2
 *     2.0.ceil      #=> 2
 *     (-1.2).ceil   #=> -1
 *     (-2.0).ceil   #=> -2
 */

static VALUE
flo_ceil(num)
    VALUE num;
{
    double f = ceil(RFLOAT(num)->value);
    long val;

    if (!FIXABLE(f)) {
    return rb_dbl2big(f);
    }
    val = f;
    return LONG2FIX(val);
}

#coerce ⇒ Object

MISSING: documentation




# File 'numeric.c'

/*
 * MISSING: documentation
 */

static VALUE
flo_coerce(x, y)
    VALUE x, y;
{
    return rb_assoc_new(rb_Float(y), x);
}

#divmod(numeric) ⇒ Array

See Numeric#divmod.

Returns:




# File 'numeric.c'

/*
 *  call-seq:
 *     flt.divmod(numeric)    => array
 *
 *  See <code>Numeric#divmod</code>.
 */

static VALUE
flo_divmod(x, y)
    VALUE x, y;
{
    double fy, div, mod, val;
    volatile VALUE a, b;

    switch (TYPE(y)) {
      case T_FIXNUM:
    fy = (double)FIX2LONG(y);
    break;
      case T_BIGNUM:
    fy = rb_big2dbl(y);
    break;
      case T_FLOAT:
    fy = RFLOAT(y)->value;
    break;
      default:
    return rb_num_coerce_bin(x, y);
    }
    flodivmod(RFLOAT(x)->value, fy, &div, &mod);
    if (FIXABLE(div)) {
        val = round(div);
    a = LONG2FIX(val);
    }
    else {
    a = rb_dbl2big(div);
    }
    b = rb_float_new(mod);
    return rb_assoc_new(a, b);
}

#eql?(obj) ⇒ Boolean

Returns true only if obj is a Float with the same value as flt. Contrast this with Float#==, which performs type conversions.

1.0.eql?(1)   #=> false

Returns:

  • (Boolean) 



# File 'numeric.c'

/*
 *  call-seq:
 *     flt.eql?(obj)   => true or false
 *
 *  Returns <code>true</code> only if <i>obj</i> is a
 *  <code>Float</code> with the same value as <i>flt</i>. Contrast this
 *  with <code>Float#==</code>, which performs type conversions.
 *
 *     1.0.eql?(1)   #=> false
 */

static VALUE
flo_eql(x, y)
    VALUE x, y;
{
    if (TYPE(y) == T_FLOAT) {
    double a = RFLOAT(x)->value;
    double b = RFLOAT(y)->value;

    if (isnan(a) || isnan(b)) return Qfalse;
    if (a == b) return Qtrue;
    }
    return Qfalse;
}

#finite? ⇒ Boolean

Returns true if flt is a valid IEEE floating point number (it is not infinite, and nan? is false).

Returns:

  • (Boolean) 



# File 'numeric.c'

/*
 *  call-seq:
 *     flt.finite? -> true or false
 *
 *  Returns <code>true</code> if <i>flt</i> is a valid IEEE floating
 *  point number (it is not infinite, and <code>nan?</code> is
 *  <code>false</code>).
 *
 */

static VALUE
flo_is_finite_p(num)
     VALUE num;
{
    double value = RFLOAT(num)->value;

#if HAVE_FINITE
    if (!finite(value))
    return Qfalse;
#else
    if (isinf(value) || isnan(value))
    return Qfalse;
#endif

    return Qtrue;
}

#floor ⇒ Integer

Returns the largest integer less than or equal to flt.

1.2.floor      #=> 1
2.0.floor      #=> 2
(-1.2).floor   #=> -2
(-2.0).floor   #=> -2

Returns:




# File 'numeric.c'

/*
 *  call-seq:
 *     flt.floor   => integer
 *
 *  Returns the largest integer less than or equal to <i>flt</i>.
 *
 *     1.2.floor      #=> 1
 *     2.0.floor      #=> 2
 *     (-1.2).floor   #=> -2
 *     (-2.0).floor   #=> -2
 */

static VALUE
flo_floor(num)
    VALUE num;
{
    double f = floor(RFLOAT(num)->value);
    long val;

    if (!FIXABLE(f)) {
    return rb_dbl2big(f);
    }
    val = f;
    return LONG2FIX(val);
}

#hash ⇒ Integer

Returns a hash code for this float.

Returns:




# File 'numeric.c'

/*
 * call-seq:
 *   flt.hash   => integer
 *
 * Returns a hash code for this float.
 */

static VALUE
flo_hash(num)
    VALUE num;
{
    double d;
    char *c;
    int i, hash;

    d = RFLOAT(num)->value;
    if (d == 0) d = fabs(d);
    c = (char*)&d;
    for (hash=0, i=0; i<sizeof(double);i++) {
    hash = (hash * 971) ^ (unsigned char)c[i];
    }
    if (hash < 0) hash = -hash;
    return INT2FIX(hash);
}

#infinite? ⇒ nil, ...

Returns nil, -1, or 1 depending on whether flt is finite, -infinity, or infinity.

(0.0).infinite?        #=> nil
(-1.0/0.0).infinite?   #=> -1
(+1.0/0.0).infinite?   #=> 1

Returns:

  • (nil, -1, +1) 



# File 'numeric.c'

/*
 *  call-seq:
 *     flt.infinite? -> nil, -1, +1
 *
 *  Returns <code>nil</code>, -1, or +1 depending on whether <i>flt</i>
 *  is finite, -infinity, or +infinity.
 *
 *     (0.0).infinite?        #=> nil
 *     (-1.0/0.0).infinite?   #=> -1
 *     (+1.0/0.0).infinite?   #=> 1
 */

static VALUE
flo_is_infinite_p(num)
     VALUE num;
{
    double value = RFLOAT(num)->value;

    if (isinf(value)) {
    return INT2FIX( value < 0 ? -1 : 1 );
    }

    return Qnil;
}

#%(other) ⇒ Float #modulo(other) ⇒ Float

Return the modulo after division of flt by other.

6543.21.modulo(137)      #=> 104.21
6543.21.modulo(137.24)   #=> 92.9299999999996

Overloads:




# File 'numeric.c'

/*
 *  call-seq:
 *     flt % other         => float
 *     flt.modulo(other)   => float
 *
 *  Return the modulo after division of <code>flt</code> by <code>other</code>.
 *
 *     6543.21.modulo(137)      #=> 104.21
 *     6543.21.modulo(137.24)   #=> 92.9299999999996
 */

static VALUE
flo_mod(x, y)
    VALUE x, y;
{
    double fy, mod;

    switch (TYPE(y)) {
      case T_FIXNUM:
    fy = (double)FIX2LONG(y);
    break;
      case T_BIGNUM:
    fy = rb_big2dbl(y);
    break;
      case T_FLOAT:
    fy = RFLOAT(y)->value;
    break;
      default:
    return rb_num_coerce_bin(x, y);
    }
    flodivmod(RFLOAT(x)->value, fy, 0, &mod);
    return rb_float_new(mod);
}

#nan? ⇒ Boolean

Returns true if flt is an invalid IEEE floating point number.

a = -1.0      #=> -1.0
a.nan?        #=> false
a = 0.0/0.0   #=> NaN
a.nan?        #=> true

Returns:

  • (Boolean) 



# File 'numeric.c'

/*
 *  call-seq:
 *     flt.nan? -> true or false
 *
 *  Returns <code>true</code> if <i>flt</i> is an invalid IEEE floating
 *  point number.
 *
 *     a = -1.0      #=> -1.0
 *     a.nan?        #=> false
 *     a = 0.0/0.0   #=> NaN
 *     a.nan?        #=> true
 */

static VALUE
flo_is_nan_p(num)
     VALUE num;
{
    double value = RFLOAT(num)->value;

    return isnan(value) ? Qtrue : Qfalse;
}

#round ⇒ Integer

Rounds flt to the nearest integer. Equivalent to:

def round
  return (self+0.5).floor if self > 0.0
  return (self-0.5).ceil  if self < 0.0
  return 0
end

1.5.round      #=> 2
(-1.5).round   #=> -2

Returns:




# File 'numeric.c'

/*
 *  call-seq:
 *     flt.round   => integer
 *
 *  Rounds <i>flt</i> to the nearest integer. Equivalent to:
 *
 *     def round
 *       return (self+0.5).floor if self > 0.0
 *       return (self-0.5).ceil  if self < 0.0
 *       return 0
 *     end
 *
 *     1.5.round      #=> 2
 *     (-1.5).round   #=> -2
 *
 */

static VALUE
flo_round(num)
    VALUE num;
{
    double f = RFLOAT(num)->value;
    long val;

    f = round(f);

    if (!FIXABLE(f)) {
    return rb_dbl2big(f);
    }
    val = f;
    return LONG2FIX(val);
}

#to_f ⇒ Object

As flt is already a float, returns self.




# File 'numeric.c'

/*
 * call-seq:
 *   flt.to_f   => flt
 *
 * As <code>flt</code> is already a float, returns <i>self</i>.
 */

static VALUE
flo_to_f(num)
    VALUE num;
{
    return num;
}

#to_i ⇒ Integer #to_int ⇒ Integer #truncate ⇒ Integer

Returns flt truncated to an Integer.

Overloads:




# File 'numeric.c'

/*
 *  call-seq:
 *     flt.to_i       => integer
 *     flt.to_int     => integer
 *     flt.truncate   => integer
 *
 *  Returns <i>flt</i> truncated to an <code>Integer</code>.
 */

static VALUE
flo_truncate(num)
    VALUE num;
{
    double f = RFLOAT(num)->value;
    long val;

    if (f > 0.0) f = floor(f);
    if (f < 0.0) f = ceil(f);

    if (!FIXABLE(f)) {
    return rb_dbl2big(f);
    }
    val = f;
    return LONG2FIX(val);
}

#to_i ⇒ Integer #to_int ⇒ Integer #truncate ⇒ Integer

Returns flt truncated to an Integer.

Overloads:




# File 'numeric.c'

/*
 *  call-seq:
 *     flt.to_i       => integer
 *     flt.to_int     => integer
 *     flt.truncate   => integer
 *
 *  Returns <i>flt</i> truncated to an <code>Integer</code>.
 */

static VALUE
flo_truncate(num)
    VALUE num;
{
    double f = RFLOAT(num)->value;
    long val;

    if (f > 0.0) f = floor(f);
    if (f < 0.0) f = ceil(f);

    if (!FIXABLE(f)) {
    return rb_dbl2big(f);
    }
    val = f;
    return LONG2FIX(val);
}

#to_s ⇒ String

Returns a string containing a representation of self. As well as a fixed or exponential form of the number, the call may return "NaN", "Infinity", and "-Infinity".

Returns:




# File 'numeric.c'

/*
 *  call-seq:
 *     flt.to_s    => string
 *
 *  Returns a string containing a representation of self. As well as a
 *  fixed or exponential form of the number, the call may return
 *  ``<code>NaN</code>'', ``<code>Infinity</code>'', and
 *  ``<code>-Infinity</code>''.
 */

static VALUE
flo_to_s(flt)
    VALUE flt;
{
    char buf[32];
    double value = RFLOAT(flt)->value;
    char *p, *e;

    if (isinf(value))
    return rb_str_new2(value < 0 ? "-Infinity" : "Infinity");
    else if(isnan(value))
    return rb_str_new2("NaN");

    sprintf(buf, "%#.15g", value); /* ensure to print decimal point */
    if (!(e = strchr(buf, 'e'))) {
    e = buf + strlen(buf);
    }
    if (!ISDIGIT(e[-1])) { /* reformat if ended with decimal point (ex 111111111111111.) */
    sprintf(buf, "%#.14e", value);
    if (!(e = strchr(buf, 'e'))) {
        e = buf + strlen(buf);
    }
    }
    p = e;
    while (p[-1]=='0' && ISDIGIT(p[-2]))
    p--;
    memmove(p, e, strlen(e)+1);
    return rb_str_new2(buf);
}

#to_i ⇒ Integer #to_int ⇒ Integer #truncate ⇒ Integer

Returns flt truncated to an Integer.

Overloads:




# File 'numeric.c'

/*
 *  call-seq:
 *     flt.to_i       => integer
 *     flt.to_int     => integer
 *     flt.truncate   => integer
 *
 *  Returns <i>flt</i> truncated to an <code>Integer</code>.
 */

static VALUE
flo_truncate(num)
    VALUE num;
{
    double f = RFLOAT(num)->value;
    long val;

    if (f > 0.0) f = floor(f);
    if (f < 0.0) f = ceil(f);

    if (!FIXABLE(f)) {
    return rb_dbl2big(f);
    }
    val = f;
    return LONG2FIX(val);
}

#zero? ⇒ Boolean

Returns true if flt is 0.0.

Returns:

  • (Boolean) 



# File 'numeric.c'

/*
 *  call-seq:
 *     flt.zero? -> true or false
 *
 *  Returns <code>true</code> if <i>flt</i> is 0.0.
 *
 */

static VALUE
flo_zero_p(num)
    VALUE num;
{
    if (RFLOAT(num)->value == 0.0) {
    return Qtrue;
    }
    return Qfalse;
}