Class: Float

Inherits:
Numeric show all
Defined in:
src/numeric.c

Overview

15.2.9

Instance Method Summary collapse

Methods inherited from Numeric

#[email protected], #[email protected], #abs, #negative?, #nonzero?, #positive?, #to_r, #zero?

Methods included from Comparable

#<, #<=, #>, #>=, #between?, #clamp

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:


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# File 'src/numeric.c', line 343

static mrb_value
flo_mod(mrb_state *mrb, mrb_value x)
{
  mrb_value y;
  mrb_float mod;

  mrb_get_args(mrb, "o", &y);

  flodivmod(mrb, mrb_float(x), mrb_to_flo(mrb, y), 0, &mod);
  return mrb_float_value(mrb, mod);
}

#&Object


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# File 'src/numeric.c', line 1037

static mrb_value flo_and(mrb_state *mrb, mrb_value x);

#*(other) ⇒ Float

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

Returns:


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# File 'src/numeric.c', line 281

static mrb_value
flo_mul(mrb_state *mrb, mrb_value x)
{
  mrb_value y;

  mrb_get_args(mrb, "o", &y);
  return mrb_float_value(mrb, mrb_float(x) * mrb_to_flo(mrb, y));
}

#+Object

15.2.9.3.1


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# File 'src/numeric.c', line 1597

static mrb_value
flo_plus(mrb_state *mrb, mrb_value x)
{
  mrb_value y;

  mrb_get_args(mrb, "o", &y);
  return mrb_float_value(mrb, mrb_float(x) + mrb_to_flo(mrb, y));
}

#-(other) ⇒ Float

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

Returns:


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# File 'src/numeric.c', line 263

static mrb_value
flo_minus(mrb_state *mrb, mrb_value x)
{
  mrb_value y;

  mrb_get_args(mrb, "o", &y);
  return mrb_float_value(mrb, mrb_float(x) - mrb_to_flo(mrb, y));
}

#<<Object


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# File 'src/numeric.c', line 535

static mrb_value
flo_lshift(mrb_state *mrb, mrb_value x)
{
  mrb_int width;

  mrb_get_args(mrb, "i", &width);
  return flo_shift(mrb, x, width);
}

#==(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)

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# File 'src/numeric.c', line 402

static mrb_value
flo_eq(mrb_state *mrb, mrb_value x)
{
  mrb_value y;
  mrb_get_args(mrb, "o", &y);

  switch (mrb_type(y)) {
  case MRB_TT_FIXNUM:
    return mrb_bool_value(mrb_float(x) == (mrb_float)mrb_fixnum(y));
  case MRB_TT_FLOAT:
    return mrb_bool_value(mrb_float(x) == mrb_float(y));
  default:
    return mrb_false_value();
  }
}

#>>Object


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# File 'src/numeric.c', line 526

static mrb_value
flo_rshift(mrb_state *mrb, mrb_value x)
{
  mrb_int width;

  mrb_get_args(mrb, "i", &width);
  return flo_shift(mrb, x, -width);
}

#^Object


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# File 'src/numeric.c', line 1039

static mrb_value flo_xor(mrb_state *mrb, mrb_value x);

#ceilInteger

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:


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# File 'src/numeric.c', line 646

static mrb_value
flo_ceil(mrb_state *mrb, mrb_value num)
{
  mrb_float f = ceil(mrb_float(num));

  mrb_check_num_exact(mrb, f);
  return mrb_int_value(mrb, f);
}

#divmodObject

15.2.9.3.15


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# File 'src/numeric.c', line 967

static mrb_value
flo_divmod(mrb_state *mrb, mrb_value x)
{
  mrb_value y;
  mrb_float div, mod;
  mrb_value a, b;

  mrb_get_args(mrb, "o", &y);

  flodivmod(mrb, mrb_float(x), mrb_to_flo(mrb, y), &div, &mod);
  a = mrb_int_value(mrb, div);
  b = mrb_float_value(mrb, mod);
  return mrb_assoc_new(mrb, a, b);
}

#eql?Boolean

15.2.8.3.16

Returns:

  • (Boolean)

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# File 'src/numeric.c', line 379

static mrb_value
flo_eql(mrb_state *mrb, mrb_value x)
{
  mrb_value y;

  mrb_get_args(mrb, "o", &y);
  if (!mrb_float_p(y)) return mrb_false_value();
  return mrb_bool_value(mrb_float(x) == mrb_float(y));
}

#finite?Boolean

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

Returns:

  • (Boolean)

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# File 'src/numeric.c', line 593

static mrb_value
flo_finite_p(mrb_state *mrb, mrb_value num)
{
  return mrb_bool_value(isfinite(mrb_float(num)));
}

#floorInteger

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:


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# File 'src/numeric.c', line 623

static mrb_value
flo_floor(mrb_state *mrb, mrb_value num)
{
  mrb_float f = floor(mrb_float(num));

  mrb_check_num_exact(mrb, f);
  return mrb_int_value(mrb, f);
}

#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)

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# File 'src/numeric.c', line 571

static mrb_value
flo_infinite_p(mrb_state *mrb, mrb_value num)
{
  mrb_float value = mrb_float(num);

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

#to_sString

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:


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# File 'src/numeric.c', line 209

static mrb_value
flo_to_s(mrb_state *mrb, mrb_value flt)
{
  mrb_float f = mrb_float(flt);

  if (isinf(f)) {
    return f < 0 ? mrb_str_new_lit(mrb, "-Infinity")
                 : mrb_str_new_lit(mrb, "Infinity");
  }
  else if (isnan(f)) {
    return mrb_str_new_lit(mrb, "NaN");
  }
  else {
    char fmt[] = "%." MRB_STRINGIZE(FLO_TO_STR_PREC) "g";
    mrb_value str = mrb_float_to_str(mrb, flt, fmt);
    mrb_int len;
    char *begp, *p, *endp;

    insert_dot_zero:
    begp = RSTRING_PTR(str);
    len = RSTRING_LEN(str);
    for (p = begp, endp = p + len; p < endp; ++p) {
      if (*p == '.') {
        return str;
      }
      else if (*p == 'e') {
        ptrdiff_t e_pos = p - begp;
        mrb_str_cat(mrb, str, ".0", 2);
        p = RSTRING_PTR(str) + e_pos;
        memmove(p + 2, p, len - e_pos);
        memcpy(p, ".0", 2);
        return str;
      }
    }

    if (FLO_TO_STR_PREC + (begp[0] == '-') <= len) {
      --fmt[sizeof(fmt) - 3];  /* %.16g(%.8g) -> %.15g(%.7g) */
      str = mrb_float_to_str(mrb, flt, fmt);
      goto insert_dot_zero;
    }

    return str;
  }
}

#nan?Boolean

Returns:

  • (Boolean)

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# File 'src/numeric.c', line 759

static mrb_value
flo_nan_p(mrb_state *mrb, mrb_value num)
{
  return mrb_bool_value(isnan(mrb_float(num)));
}

#round([ndigits]) ⇒ Integer, Float

Rounds flt to a given precision in decimal digits (default 0 digits). Precision may be negative. Returns a floating point number when ndigits is more than zero.

1.4.round #=> 1 1.5.round #=> 2 1.6.round #=> 2 (-1.5).round #=> -2

1.234567.round(2) #=> 1.23 1.234567.round(3) #=> 1.235 1.234567.round(4) #=> 1.2346 1.234567.round(5) #=> 1.23457

34567.89.round(-5) #=> 0 34567.89.round(-4) #=> 30000 34567.89.round(-3) #=> 35000 34567.89.round(-2) #=> 34600 34567.89.round(-1) #=> 34570 34567.89.round(0) #=> 34568 34567.89.round(1) #=> 34567.9 34567.89.round(2) #=> 34567.89 34567.89.round(3) #=> 34567.89

Returns:


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# File 'src/numeric.c', line 686

static mrb_value
flo_round(mrb_state *mrb, mrb_value num)
{
  double number, f;
  mrb_int ndigits = 0;
  mrb_int i;

  mrb_get_args(mrb, "|i", &ndigits);
  number = mrb_float(num);

  if (0 < ndigits && (isinf(number) || isnan(number))) {
    return num;
  }
  mrb_check_num_exact(mrb, number);

  f = 1.0;
  i = ndigits >= 0 ? ndigits : -ndigits;
  if (ndigits > DBL_DIG+2) return num;
  while  (--i >= 0)
    f = f*10.0;

  if (isinf(f)) {
    if (ndigits < 0) number = 0;
  }
  else {
    double d;

    if (ndigits < 0) number /= f;
    else number *= f;

    /* home-made inline implementation of round(3) */
    if (number > 0.0) {
      d = floor(number);
      number = d + (number - d >= 0.5);
    }
    else if (number < 0.0) {
      d = ceil(number);
      number = d - (d - number >= 0.5);
    }

    if (ndigits < 0) number *= f;
    else number /= f;
  }

  if (ndigits > 0) {
    if (!isfinite(number)) return num;
    return mrb_float_value(mrb, number);
  }
  return mrb_int_value(mrb, number);
}

#to_fself

As flt is already a float, returns +self+.

Returns:

  • (self)

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# File 'src/numeric.c', line 552

static mrb_value
flo_to_f(mrb_state *mrb, mrb_value num)
{
  return num;
}

#to_iInteger #truncateInteger

Returns flt truncated to an Integer.

Overloads:


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# File 'src/numeric.c', line 747

static mrb_value
flo_truncate(mrb_state *mrb, mrb_value num)
{
  mrb_float f = mrb_float(num);

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

  mrb_check_num_exact(mrb, f);
  return mrb_int_value(mrb, f);
}

#to_iInteger #truncateInteger

Returns flt truncated to an Integer.

Overloads:


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# File 'src/numeric.c', line 747

static mrb_value
flo_truncate(mrb_state *mrb, mrb_value num)
{
  mrb_float f = mrb_float(num);

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

  mrb_check_num_exact(mrb, f);
  return mrb_int_value(mrb, f);
}

#to_sString

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:


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# File 'src/numeric.c', line 209

static mrb_value
flo_to_s(mrb_state *mrb, mrb_value flt)
{
  mrb_float f = mrb_float(flt);

  if (isinf(f)) {
    return f < 0 ? mrb_str_new_lit(mrb, "-Infinity")
                 : mrb_str_new_lit(mrb, "Infinity");
  }
  else if (isnan(f)) {
    return mrb_str_new_lit(mrb, "NaN");
  }
  else {
    char fmt[] = "%." MRB_STRINGIZE(FLO_TO_STR_PREC) "g";
    mrb_value str = mrb_float_to_str(mrb, flt, fmt);
    mrb_int len;
    char *begp, *p, *endp;

    insert_dot_zero:
    begp = RSTRING_PTR(str);
    len = RSTRING_LEN(str);
    for (p = begp, endp = p + len; p < endp; ++p) {
      if (*p == '.') {
        return str;
      }
      else if (*p == 'e') {
        ptrdiff_t e_pos = p - begp;
        mrb_str_cat(mrb, str, ".0", 2);
        p = RSTRING_PTR(str) + e_pos;
        memmove(p + 2, p, len - e_pos);
        memcpy(p, ".0", 2);
        return str;
      }
    }

    if (FLO_TO_STR_PREC + (begp[0] == '-') <= len) {
      --fmt[sizeof(fmt) - 3];  /* %.16g(%.8g) -> %.15g(%.7g) */
      str = mrb_float_to_str(mrb, flt, fmt);
      goto insert_dot_zero;
    }

    return str;
  }
}

#to_iInteger #truncateInteger

Returns flt truncated to an Integer.

Overloads:


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# File 'src/numeric.c', line 747

static mrb_value
flo_truncate(mrb_state *mrb, mrb_value num)
{
  mrb_float f = mrb_float(num);

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

  mrb_check_num_exact(mrb, f);
  return mrb_int_value(mrb, f);
}

#|Object


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# File 'src/numeric.c', line 1038

static mrb_value flo_or(mrb_state *mrb, mrb_value x);

#~Object

15.2.9.3.7


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# File 'src/numeric.c', line 444

static mrb_value
flo_rev(mrb_state *mrb, mrb_value x)
{
  int64_t v1;
  v1 = (int64_t)mrb_float(x);
  return int64_value(mrb, ~v1);
}