In Files

  • numeric.c

Fixnum

A Fixnum holds Integer values that can be represented in a native machine word (minus 1 bit). If any operation on a Fixnum exceeds this range, the value is automatically converted to a Bignum.

Fixnum objects have immediate value. This means that when they are assigned or passed as parameters, the actual object is passed, rather than a reference to that object. Assignment does not alias Fixnum objects. There is effectively only one Fixnum object instance for any given integer value, so, for example, you cannot add a singleton method to a Fixnum.

Public Class Methods

induced_from(obj) => fixnum click to toggle source

Convert obj to a Fixnum. Works with numeric parameters. Also works with Symbols, but this is deprecated.

 
               static VALUE
rb_fix_induced_from(klass, x)
    VALUE klass, x;
{
    return rb_num2fix(x);
}
            

Public Instance Methods

fix % other => Numeric click to toggle source

Returns fix modulo other. See Numeric.divmod for more information.

 
               static VALUE
fix_mod(x, y)
    VALUE x, y;
{
    if (FIXNUM_P(y)) {
        long mod;

        fixdivmod(FIX2LONG(x), FIX2LONG(y), 0, &mod);
        return LONG2NUM(mod);
    }
    return rb_num_coerce_bin(x, y);
}
            
fix & other => integer click to toggle source

Bitwise AND.

 
               static VALUE
fix_and(x, y)
    VALUE x, y;
{
    long val;

    if (!FIXNUM_P(y = fix_coerce(y))) {
        return rb_big_and(y, x);
    }
    val = FIX2LONG(x) & FIX2LONG(y);
    return LONG2NUM(val);
}
            
fix * numeric => numeric_result click to toggle source

Performs multiplication: the class of the resulting object depends on the class of numeric and on the magnitude of the result.

 
               static VALUE
fix_mul(x, y)
    VALUE x, y;
{
    if (FIXNUM_P(y)) {
#ifdef __HP_cc
        /* avoids an optimization bug of HP aC++/ANSI C B3910B A.06.05 [Jul 25 2005] */
        volatile
#endif
        long a, b, c;
        VALUE r;

        a = FIX2LONG(x);
        if (a == 0) return x;

        b = FIX2LONG(y);
        c = a * b;
        r = LONG2FIX(c);

        if (FIX2LONG(r) != c || c/a != b) {
            r = rb_big_mul(rb_int2big(a), rb_int2big(b));
        }
        return r;
    }
    if (TYPE(y) == T_FLOAT) {
        return rb_float_new((double)FIX2LONG(x) * RFLOAT(y)->value);
    }
    return rb_num_coerce_bin(x, y);
}
            
fix ** other => Numeric click to toggle source

Raises fix to the other power, which may be negative or fractional.

2 ** 3      #=> 8
2 ** -1     #=> 0.5
2 ** 0.5    #=> 1.4142135623731
 
               static VALUE
fix_pow(x, y)
    VALUE x, y;
{
    static const double zero = 0.0;
    long a = FIX2LONG(x);

    if (FIXNUM_P(y)) {
        long b;

        b = FIX2LONG(y);
        if (b == 0) return INT2FIX(1);
        if (b == 1) return x;
        a = FIX2LONG(x);
        if (a == 0) {
            if (b > 0) return INT2FIX(0);
            return rb_float_new(1.0 / zero);
        }
        if (a == 1) return INT2FIX(1);
        if (a == -1) {
            if (b % 2 == 0)
                return INT2FIX(1);
            else 
                return INT2FIX(-1);
        }
        if (b > 0) {
            return rb_big_pow(rb_int2big(a), y);
        }
        return rb_float_new(pow((double)a, (double)b));
    }
    switch (TYPE(y)) {
      case T_BIGNUM:
        if (a == 0) return INT2FIX(0);
        if (a == 1) return INT2FIX(1);
        if (a == -1) {
            if (int_even_p(y)) return INT2FIX(1);
            else return INT2FIX(-1);
        }
        x = rb_int2big(FIX2LONG(x));
        return rb_big_pow(x, y);
      case T_FLOAT:
        if (a == 0) {
            return rb_float_new(RFLOAT(y)->value < 0 ? (1.0 / zero) : 0.0);
        }
        if (a == 1) return rb_float_new(1.0);
        return rb_float_new(pow((double)a, RFLOAT(y)->value));
      default:
        return rb_num_coerce_bin(x, y);
    }
}
            
fix + numeric => numeric_result click to toggle source

Performs addition: the class of the resulting object depends on the class of numeric and on the magnitude of the result.

 
               static VALUE
fix_plus(x, y)
    VALUE x, y;
{
    if (FIXNUM_P(y)) {
        long a, b, c;
        VALUE r;

        a = FIX2LONG(x);
        b = FIX2LONG(y);
        c = a + b;
        r = LONG2NUM(c);

        return r;
    }
    if (TYPE(y) == T_FLOAT) {
        return rb_float_new((double)FIX2LONG(x) + RFLOAT(y)->value);
    }
    return rb_num_coerce_bin(x, y);
}
            
fix - numeric => numeric_result click to toggle source

Performs subtraction: the class of the resulting object depends on the class of numeric and on the magnitude of the result.

 
               static VALUE
fix_minus(x, y)
    VALUE x, y;
{
    if (FIXNUM_P(y)) {
        long a, b, c;
        VALUE r;

        a = FIX2LONG(x);
        b = FIX2LONG(y);
        c = a - b;
        r = LONG2NUM(c);

        return r;
    }
    if (TYPE(y) == T_FLOAT) {
        return rb_float_new((double)FIX2LONG(x) - RFLOAT(y)->value);
    }
    return rb_num_coerce_bin(x, y);
}
            
-fix => integer click to toggle source

Negates fix (which might return a Bignum).

 
               static VALUE
fix_uminus(num)
    VALUE num;
{
    return LONG2NUM(-FIX2LONG(num));
}
            
fix / numeric => numeric_result click to toggle source

Performs division: the class of the resulting object depends on the class of numeric and on the magnitude of the result.

 
               static VALUE
fix_div(x, y)
    VALUE x, y;
{
    if (FIXNUM_P(y)) {
        long div;

        fixdivmod(FIX2LONG(x), FIX2LONG(y), &div, 0);
        return LONG2NUM(div);
    }
    return rb_num_coerce_bin(x, y);
}
            
fix < other => true or false click to toggle source

Returns true if the value of fix is less than that of other.

 
               static VALUE
fix_lt(x, y)
    VALUE x, y;
{
    if (FIXNUM_P(y)) {
        long a = FIX2LONG(x), b = FIX2LONG(y);

        if (a < b) return Qtrue;
        return Qfalse;
    }
    else {
        return rb_num_coerce_relop(x, y);
    }
}
            
fix << count => integer click to toggle source

Shifts fix left count positions (right if count is negative).

 
               static VALUE
rb_fix_lshift(x, y)
    VALUE x, y;
{
    long val, width;

    val = NUM2LONG(x);
    if (!FIXNUM_P(y))
        return rb_big_lshift(rb_int2big(val), y);
    width = FIX2LONG(y);
    if (width < 0)
        return fix_rshift(val, (unsigned long)-width);
    return fix_lshift(val, width);
}
            
fix <= other => true or false click to toggle source

Returns true if the value of fix is less thanor equal to that of other.

 
               static VALUE
fix_le(x, y)
    VALUE x, y;
{
    if (FIXNUM_P(y)) {
        long a = FIX2LONG(x), b = FIX2LONG(y);

        if (a <= b) return Qtrue;
        return Qfalse;
    }
    else {
        return rb_num_coerce_relop(x, y);
    }
}
            
fix <=> numeric => -1, 0, +1 click to toggle source

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

 
               static VALUE
fix_cmp(x, y)
    VALUE x, y;
{
    if (x == y) return INT2FIX(0);
    if (FIXNUM_P(y)) {
        long a = FIX2LONG(x), b = FIX2LONG(y);

        if (a > b) return INT2FIX(1);
        return INT2FIX(-1);
    }
    else {
        return rb_num_coerce_cmp(x, y);
    }
}
            
fix == other click to toggle source

Return true if fix equals other numerically.

1 == 2      #=> false
1 == 1.0    #=> true
 
               static VALUE
fix_equal(x, y)
    VALUE x, y;
{
    if (x == y) return Qtrue;
    if (FIXNUM_P(y)) return Qfalse;
    return num_equal(x, y);
}
            
fix > other => true or false click to toggle source

Returns true if the value of fix is greater than that of other.

 
               static VALUE
fix_gt(x, y)
    VALUE x, y;
{
    if (FIXNUM_P(y)) {
        long a = FIX2LONG(x), b = FIX2LONG(y);

        if (a > b) return Qtrue;
        return Qfalse;
    }
    else {
        return rb_num_coerce_relop(x, y);
    }
}
            
fix >= other => true or false click to toggle source

Returns true if the value of fix is greater than or equal to that of other.

 
               static VALUE
fix_ge(x, y)
    VALUE x, y;
{
    if (FIXNUM_P(y)) {
        long a = FIX2LONG(x), b = FIX2LONG(y);

        if (a >= b) return Qtrue;
        return Qfalse;
    }
    else {
        return rb_num_coerce_relop(x, y);
    }
}
            
fix >> count => integer click to toggle source

Shifts fix right count positions (left if count is negative).

 
               static VALUE
rb_fix_rshift(x, y)
    VALUE x, y;
{
    long i, val;

    val = FIX2LONG(x);
    if (!FIXNUM_P(y))
        return rb_big_rshift(rb_int2big(val), y);
    i = FIX2LONG(y);
    if (i == 0) return x;
    if (i < 0)
        return fix_lshift(val, (unsigned long)-i);
    return fix_rshift(val, i);
}
            
fix[n] => 0, 1 click to toggle source

Bit Reference—Returns the nth bit in the binary representation of fix, where fix is the least significant bit.

a = 0b11001100101010
30.downto(0) do |n| print a[n] end

produces:

0000000000000000011001100101010
 
               static VALUE
fix_aref(fix, idx)
    VALUE fix, idx;
{
    long val = FIX2LONG(fix);
    long i;

    if (!FIXNUM_P(idx = fix_coerce(idx))) {
        idx = rb_big_norm(idx);
        if (!FIXNUM_P(idx)) {
            if (!RBIGNUM(idx)->sign || val >= 0)
                return INT2FIX(0);
            return INT2FIX(1);
        }
    }
    i = FIX2LONG(idx);

    if (i < 0) return INT2FIX(0);
    if (sizeof(VALUE)*CHAR_BIT-1 < i) {
        if (val < 0) return INT2FIX(1);
        return INT2FIX(0);
    }
    if (val & (1L<<i))
        return INT2FIX(1);
    return INT2FIX(0);
}
            
fix ^ other => integer click to toggle source

Bitwise EXCLUSIVE OR.

 
               static VALUE
fix_xor(x, y)
    VALUE x, y;
{
    long val;

    if (!FIXNUM_P(y = fix_coerce(y))) {
        return rb_big_xor(y, x);
    }
    val = FIX2LONG(x) ^ FIX2LONG(y);
    return LONG2NUM(val);
}
            
abs → aFixnum click to toggle source

Returns the absolute value of fix.

-12345.abs   #=> 12345
12345.abs    #=> 12345
 
               static VALUE
fix_abs(fix)
    VALUE fix;
{
    long i = FIX2LONG(fix);

    if (i < 0) i = -i;

    return LONG2NUM(i);
}
            
div(numeric) => numeric_result click to toggle source

Performs division: the class of the resulting object depends on the class of numeric and on the magnitude of the result.

 
               static VALUE
fix_div(x, y)
    VALUE x, y;
{
    if (FIXNUM_P(y)) {
        long div;

        fixdivmod(FIX2LONG(x), FIX2LONG(y), &div, 0);
        return LONG2NUM(div);
    }
    return rb_num_coerce_bin(x, y);
}
            
divmod(numeric) => array click to toggle source

See Numeric#divmod.

 
               static VALUE
fix_divmod(x, y)
    VALUE x, y;
{
    if (FIXNUM_P(y)) {
        long div, mod;

        fixdivmod(FIX2LONG(x), FIX2LONG(y), &div, &mod);

        return rb_assoc_new(LONG2NUM(div), LONG2NUM(mod));
    }
    return rb_num_coerce_bin(x, y);
}
            
id2name → string or nil click to toggle source

Returns the name of the object whose symbol id is fix. If there is no symbol in the symbol table with this value, returns nil. id2name has nothing to do with the Object.id method. See also Fixnum#to_sym, String#intern, and class Symbol.

symbol = :@inst_var    #=> :@inst_var
id     = symbol.to_i   #=> 9818
id.id2name             #=> "@inst_var"
 
               static VALUE
fix_id2name(fix)
    VALUE fix;
{
    char *name = rb_id2name(FIX2UINT(fix));
    if (name) return rb_str_new2(name);
    return Qnil;
}
            
modulo(other) => Numeric click to toggle source

Returns fix modulo other. See Numeric.divmod for more information.

 
               static VALUE
fix_mod(x, y)
    VALUE x, y;
{
    if (FIXNUM_P(y)) {
        long mod;

        fixdivmod(FIX2LONG(x), FIX2LONG(y), 0, &mod);
        return LONG2NUM(mod);
    }
    return rb_num_coerce_bin(x, y);
}
            
quo(numeric) => float click to toggle source

Returns the floating point result of dividing fix by numeric.

654321.quo(13731)      #=> 47.6528293642124
654321.quo(13731.24)   #=> 47.6519964693647
 
               static VALUE
fix_quo(x, y)
    VALUE x, y;
{
    if (FIXNUM_P(y)) {
        return rb_float_new((double)FIX2LONG(x) / (double)FIX2LONG(y));
    }
    return rb_num_coerce_bin(x, y);
}
            
size → fixnum click to toggle source

Returns the number of bytes in the machine representation of a Fixnum.

1.size            #=> 4
-1.size           #=> 4
2147483647.size   #=> 4
 
               static VALUE
fix_size(fix)
    VALUE fix;
{
    return INT2FIX(sizeof(long));
}
            
to_f → float click to toggle source

Converts fix to a Float.

 
               static VALUE
fix_to_f(num)
    VALUE num;
{
    double val;

    val = (double)FIX2LONG(num);

    return rb_float_new(val);
}
            
to_s( base=10 ) → aString click to toggle source

Returns a string containing the representation of fix radix base (between 2 and 36).

12345.to_s       #=> "12345"
12345.to_s(2)    #=> "11000000111001"
12345.to_s(8)    #=> "30071"
12345.to_s(10)   #=> "12345"
12345.to_s(16)   #=> "3039"
12345.to_s(36)   #=> "9ix"
 
               static VALUE
fix_to_s(argc, argv, x)
    int argc;
    VALUE *argv;
    VALUE x;
{
    VALUE b;
    int base;

    rb_scan_args(argc, argv, "01", &b);
    if (argc == 0) base = 10;
    else base = NUM2INT(b);

    return rb_fix2str(x, base);
}
            
to_sym → aSymbol click to toggle source

Returns the symbol whose integer value is fix. See also Fixnum#id2name.

fred = :fred.to_i
fred.id2name   #=> "fred"
fred.to_sym    #=> :fred
 
               static VALUE
fix_to_sym(fix)
    VALUE fix;
{
    ID id = FIX2UINT(fix);

    if (rb_id2name(id)) {
        return ID2SYM(id);
    }
    return Qnil;
}
            
zero? => true or false click to toggle source

Returns true if fix is zero.

 
               static VALUE
fix_zero_p(num)
    VALUE num;
{
    if (FIX2LONG(num) == 0) {
        return Qtrue;
    }
    return Qfalse;
}
            
fix | other => integer click to toggle source

Bitwise OR.

 
               static VALUE
fix_or(x, y)
    VALUE x, y;
{
    long val;

    if (!FIXNUM_P(y = fix_coerce(y))) {
        return rb_big_or(y, x);
    }
    val = FIX2LONG(x) | FIX2LONG(y);
    return LONG2NUM(val);
}
            
~fix => integer click to toggle source

One’s complement: returns a number where each bit is flipped.

 
               static VALUE
fix_rev(num)
    VALUE num;
{
    long val = FIX2LONG(num);

    val = ~val;
    return LONG2NUM(val);
}
            

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