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/ IRIX Base Documentation 2001 May / SGI IRIX Base Documentation 2001 May.iso / usr / share / catman / p_man / cat3c / frexp.z / frexp
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Text File  |  1998-10-20  |  14.8 KB  |  199 lines
  1.  
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  3.  
  4. ffffrrrreeeexxxxpppp((((3333CCCC))))                                                            ffffrrrreeeexxxxpppp((((3333CCCC))))
  5.  
  6.  
  7.  
  8. NNNNAAAAMMMMEEEE
  9.      _ffff_rrrr_eeee_xxxx_pppp, _llll_dddd_eeee_xxxx_pppp, _llll_oooo_gggg_bbbb, _iiii_llll_oooo_gggg_bbbb, _mmmm_oooo_dddd_ffff, _mmmm_oooo_dddd_ffff_ffff, _nnnn_eeee_xxxx_tttt_aaaa_ffff_tttt_eeee_rrrr, _ssss_cccc_aaaa_llll_bbbb, _ffff_rrrr_eeee_xxxx_pppp_llll, _llll_dddd_eeee_xxxx_pppp_llll,
  10.      _llll_oooo_gggg_bbbb_llll, _mmmm_oooo_dddd_ffff_llll, _nnnn_eeee_xxxx_tttt_aaaa_ffff_tttt_eeee_rrrr_llll, _ssss_cccc_aaaa_llll_bbbb_llll - manipulate parts of floating-point
  11.      numbers (libc routines)
  12.  
  13. SSSSYYYYNNNNOOOOPPPPSSSSIIIISSSS
  14.      _####_iiii_nnnn_cccc_llll_uuuu_dddd_eeee _<<<<_mmmm_aaaa_tttt_hhhh_...._hhhh_>>>>
  15.  
  16.      _dddd_oooo_uuuu_bbbb_llll_eeee _ffff_rrrr_eeee_xxxx_pppp _((((_dddd_oooo_uuuu_bbbb_llll_eeee _vvvv_aaaa_llll_uuuu_eeee_,,,, _iiii_nnnn_tttt _****_eeee_pppp_tttt_rrrr_))))_;;;;
  17.  
  18.      _dddd_oooo_uuuu_bbbb_llll_eeee _llll_dddd_eeee_xxxx_pppp _((((_dddd_oooo_uuuu_bbbb_llll_eeee _vvvv_aaaa_llll_uuuu_eeee_,,,, _iiii_nnnn_tttt _eeee_xxxx_pppp_))))_;;;;
  19.  
  20.      _dddd_oooo_uuuu_bbbb_llll_eeee _llll_oooo_gggg_bbbb _((((_dddd_oooo_uuuu_bbbb_llll_eeee _vvvv_aaaa_llll_uuuu_eeee_))))_;;;;
  21.  
  22.      _iiii_nnnn_tttt _iiii_llll_oooo_gggg_bbbb _((((_dddd_oooo_uuuu_bbbb_llll_eeee _vvvv_aaaa_llll_uuuu_eeee_))))_;;;;
  23.  
  24.      _dddd_oooo_uuuu_bbbb_llll_eeee _nnnn_eeee_xxxx_tttt_aaaa_ffff_tttt_eeee_rrrr _((((_dddd_oooo_uuuu_bbbb_llll_eeee _vvvv_aaaa_llll_uuuu_eeee_1111_,,,, _dddd_oooo_uuuu_bbbb_llll_eeee _vvvv_aaaa_llll_uuuu_eeee_2222_))))_;;;;
  25.  
  26.      _dddd_oooo_uuuu_bbbb_llll_eeee _ssss_cccc_aaaa_llll_bbbb _((((_dddd_oooo_uuuu_bbbb_llll_eeee _vvvv_aaaa_llll_uuuu_eeee_,,,, _dddd_oooo_uuuu_bbbb_llll_eeee _eeee_xxxx_pppp_))))_;;;;
  27.  
  28.      _dddd_oooo_uuuu_bbbb_llll_eeee _mmmm_oooo_dddd_ffff _((((_dddd_oooo_uuuu_bbbb_llll_eeee _vvvv_aaaa_llll_uuuu_eeee_,,,, _dddd_oooo_uuuu_bbbb_llll_eeee _****_iiii_pppp_tttt_rrrr_))))_;;;;
  29.  
  30.      _ffff_llll_oooo_aaaa_tttt _mmmm_oooo_dddd_ffff_ffff _((((_ffff_llll_oooo_aaaa_tttt _vvvv_aaaa_llll_uuuu_eeee_,,,, _ffff_llll_oooo_aaaa_tttt _****_iiii_pppp_tttt_rrrr_))))_;;;;
  31.  
  32.      _llll_oooo_nnnn_gggg _dddd_oooo_uuuu_bbbb_llll_eeee _ffff_rrrr_eeee_xxxx_pppp_llll _((((_llll_oooo_nnnn_gggg _dddd_oooo_uuuu_bbbb_llll_eeee _vvvv_aaaa_llll_uuuu_eeee_,,,, _iiii_nnnn_tttt _****_eeee_pppp_tttt_rrrr_))))_;;;;
  33.  
  34.      _llll_oooo_nnnn_gggg _dddd_oooo_uuuu_bbbb_llll_eeee _llll_dddd_eeee_xxxx_pppp_llll _((((_llll_oooo_nnnn_gggg _dddd_oooo_uuuu_bbbb_llll_eeee _vvvv_aaaa_llll_uuuu_eeee_,,,, _iiii_nnnn_tttt _eeee_xxxx_pppp_))))_;;;;
  35.  
  36.      _llll_oooo_nnnn_gggg _dddd_oooo_uuuu_bbbb_llll_eeee _llll_oooo_gggg_bbbb_llll _((((_llll_oooo_nnnn_gggg _dddd_oooo_uuuu_bbbb_llll_eeee _vvvv_aaaa_llll_uuuu_eeee_))))_;;;;
  37.  
  38.      _llll_oooo_nnnn_gggg _dddd_oooo_uuuu_bbbb_llll_eeee _nnnn_eeee_xxxx_tttt_aaaa_ffff_tttt_eeee_rrrr_llll _((((_llll_oooo_nnnn_gggg _dddd_oooo_uuuu_bbbb_llll_eeee _vvvv_aaaa_llll_uuuu_eeee_1111_,,,, _llll_oooo_nnnn_gggg _dddd_oooo_uuuu_bbbb_llll_eeee _vvvv_aaaa_llll_uuuu_eeee_2222_))))_;;;;
  39.  
  40.      _llll_oooo_nnnn_gggg _dddd_oooo_uuuu_bbbb_llll_eeee _ssss_cccc_aaaa_llll_bbbb_llll _((((_llll_oooo_nnnn_gggg _dddd_oooo_uuuu_bbbb_llll_eeee _vvvv_aaaa_llll_uuuu_eeee_,,,, _llll_oooo_nnnn_gggg _dddd_oooo_uuuu_bbbb_llll_eeee _eeee_xxxx_pppp_))))_;;;;
  41.  
  42.      _llll_oooo_nnnn_gggg _dddd_oooo_uuuu_bbbb_llll_eeee _mmmm_oooo_dddd_ffff_llll _((((_llll_oooo_nnnn_gggg _dddd_oooo_uuuu_bbbb_llll_eeee _vvvv_aaaa_llll_uuuu_eeee_,,,, _llll_oooo_nnnn_gggg _dddd_oooo_uuuu_bbbb_llll_eeee _****_iiii_pppp_tttt_rrrr_))))_;;;;
  43.  
  44. DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
  45.      (Note that the long double routines are only valid for the MIPSpro
  46.      compilers.)  Long double functions have been renamed to be compliant with
  47.      the ANSI-C standard, however to be backward compatible, they may still be
  48.      called with the double precision function name prefixed with a q.
  49.  
  50.      Every non-zero number can be written uniquely as _x*2**_n, where the
  51.      ``mantissa'' (fraction) _x is in the range 0.5 _< |_x| < 1.0, and the
  52.      ``exponent'' _n is an integer.  _ffff_rrrr_eeee_xxxx_pppp returns the mantissa of a double
  53.      _v_a_l_u_e, and stores the exponent indirectly in the location pointed to by
  54.      _e_p_t_r.  If _v_a_l_u_e is zero, both results returned by _ffff_rrrr_eeee_xxxx_pppp are zero.
  55.  
  56.      _ffff_rrrr_eeee_xxxx_pppp_llll returns the mantissa of a long double _v_a_l_u_e, and stores the
  57.      exponent indirectly in the location pointed to by _e_p_t_r.  If _v_a_l_u_e is
  58.      zero, both results returned by _ffff_rrrr_eeee_xxxx_pppp_llll are zero.
  59.  
  60.  
  61.  
  62.  
  63.                                                                         PPPPaaaaggggeeee 1111
  64.  
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  67.  
  68.  
  69.  
  70. ffffrrrreeeexxxxpppp((((3333CCCC))))                                                            ffffrrrreeeexxxxpppp((((3333CCCC))))
  71.  
  72.  
  73.  
  74.      _llll_dddd_eeee_xxxx_pppp and _ssss_cccc_aaaa_llll_bbbb return the quantity _v_a_l_u_e*2**_e_x_p.  The only difference
  75.      between the two is that _ssss_cccc_aaaa_llll_bbbb of a signaling NaN will result in the
  76.      invalid operation exception being raised.  Users should note that routine
  77.      scalb in libm43 with prototype
  78.  
  79.      _dddd_oooo_uuuu_bbbb_llll_eeee _ssss_cccc_aaaa_llll_bbbb _((((_dddd_oooo_uuuu_bbbb_llll_eeee _vvvv_aaaa_llll_uuuu_eeee_,,,, _iiii_nnnn_tttt _eeee_xxxx_pppp_))))
  80.  
  81.      conflicts with the above definition of scalb.  If it is necessary to call
  82.      the libc version of scalb in this situation, the strong name _scalb
  83.      should be used.
  84.  
  85.      _llll_dddd_eeee_xxxx_pppp_llll and _ssss_cccc_aaaa_llll_bbbb_llll return the quantity _v_a_l_u_e*2**_e_x_p.  The only difference
  86.      between the two is that _ssss_cccc_aaaa_llll_bbbb_llll of a signaling NaN will result in the
  87.      invalid operation exception being raised.
  88.  
  89.      _llll_oooo_gggg_bbbb returns the unbiased exponent of its floating-point argument as a
  90.      double-precision floating-point value.
  91.  
  92.      _iiii_llll_oooo_gggg_bbbb returns the unbiased exponent of its floating-point argument as an
  93.      integer value.  The call _iiii_llll_oooo_gggg_bbbb_((((_xxxx_)))) is equivalent to _((((_iiii_nnnn_tttt_))))_llll_oooo_gggg_bbbb_((((_xxxx_)))).
  94.  
  95.      _llll_oooo_gggg_bbbb_llll returns the unbiased exponent of its floating-point argument as a
  96.      long double-precision floating-point value.
  97.  
  98.      _mmmm_oooo_dddd_ffff , _mmmm_oooo_dddd_ffff_ffff (single-precision version) and _mmmm_oooo_dddd_ffff_llll (long double-precision
  99.      version) return the signed fractional part of _v_a_l_u_e and store the
  100.      integral part indirectly in the location pointed to by _i_p_t_r.
  101.  
  102.      _nnnn_eeee_xxxx_tttt_aaaa_ffff_tttt_eeee_rrrr returns the next representable double-precision floating-point
  103.      value following _v_a_l_u_e_1 in the direction of _v_a_l_u_e_2.  Thus, if _v_a_l_u_e_2 is
  104.      less than _v_a_l_u_e_1, _nnnn_eeee_xxxx_tttt_aaaa_ffff_tttt_eeee_rrrr returns the largest representable floating-
  105.      point number less than _v_a_l_u_e_1.
  106.  
  107.      _nnnn_eeee_xxxx_tttt_aaaa_ffff_tttt_eeee_rrrr_llll returns the next representable long double-precision
  108.      floating-point value following _v_a_l_u_e_1 in the direction of _v_a_l_u_e_2.
  109.  
  110. SSSSEEEEEEEE AAAALLLLSSSSOOOO
  111.      _cccc_cccc(1), _iiii_nnnn_tttt_rrrr_oooo(3M).
  112.  
  113. DDDDIIIIAAAAGGGGNNNNOOOOSSSSTTTTIIIICCCCSSSS
  114.      If _llll_dddd_eeee_xxxx_pppp or _llll_dddd_eeee_xxxx_pppp_llll would cause overflow, _++++_____HHHH_UUUU_GGGG_EEEE______VVVV_AAAA_LLLL (defined in _mmmm_aaaa_tttt_hhhh_...._hhhh) is
  115.      returned (according to the sign of _v_a_l_u_e), and _eeee_rrrr_rrrr_nnnn_oooo is set to _EEEE_RRRR_AAAA_NNNN_GGGG_EEEE.
  116.      If _llll_dddd_eeee_xxxx_pppp or _llll_dddd_eeee_xxxx_pppp_llll would cause underflow, zero is returned and _eeee_rrrr_rrrr_nnnn_oooo is
  117.      set to _EEEE_RRRR_AAAA_NNNN_GGGG_EEEE.  If the input _v_a_l_u_e to _llll_dddd_eeee_xxxx_pppp or _llll_dddd_eeee_xxxx_pppp_llll is NaN, the default
  118.      quiet NaN is returned and _eeee_rrrr_rrrr_nnnn_oooo is set to _EEEE_DDDD_OOOO_MMMM.  If the input _v_a_l_u_e to
  119.      _llll_dddd_eeee_xxxx_pppp or _llll_dddd_eeee_xxxx_pppp_llll is Infinity, Infinity is returned and _eeee_rrrr_rrrr_nnnn_oooo is set to
  120.      _EEEE_RRRR_AAAA_NNNN_GGGG_EEEE.  The same error conditions apply to _ssss_cccc_aaaa_llll_bbbb and _ssss_cccc_aaaa_llll_bbbb_llll except that
  121.      a signaling NaN as input will result in the raising of the invalid
  122.      operation exception.
  123.  
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  127.  
  128.  
  129.                                                                         PPPPaaaaggggeeee 2222
  130.  
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  133.  
  134.  
  135.  
  136. ffffrrrreeeexxxxpppp((((3333CCCC))))                                                            ffffrrrreeeexxxxpppp((((3333CCCC))))
  137.  
  138.  
  139.  
  140.      _llll_oooo_gggg_bbbb and _llll_oooo_gggg_bbbb_llll of NaN returns that NaN, _llll_oooo_gggg_bbbb and _llll_oooo_gggg_bbbb_llll of infinity return
  141.      positive infinity, and _llll_oooo_gggg_bbbb and _llll_oooo_gggg_bbbb_llll of zero return negative infinity
  142.      and result in the raising of the divide by zero exception.  In each of
  143.      these conditions _eeee_rrrr_rrrr_nnnn_oooo is set to _EEEE_DDDD_OOOO_MMMM.
  144.  
  145.      _iiii_llll_oooo_gggg_bbbb of NaN or zero returns _I_N_T__M_I_N, _iiii_llll_oooo_gggg_bbbb of +infinity or -infinity
  146.      returns _I_N_T__M_A_X.  In each of these conditions _eeee_rrrr_rrrr_nnnn_oooo is _n_o_t set.
  147.  
  148.      If input _v_a_l_u_e_1 to _nnnn_eeee_xxxx_tttt_aaaa_ffff_tttt_eeee_rrrr or _nnnn_eeee_xxxx_tttt_aaaa_ffff_tttt_eeee_rrrr_llll is positive or negative
  149.      infinity, that input is returned and _eeee_rrrr_rrrr_nnnn_oooo is set to _EEEE_DDDD_OOOO_MMMM.  The overflow
  150.      and inexact exceptions are signalled when input _v_a_l_u_e_1 is finite, but
  151.      _nnnn_eeee_xxxx_tttt_aaaa_ffff_tttt_eeee_rrrr_((((_v_a_l_u_e_1_,,,, _v_a_l_u_e_2_)))) or _nnnn_eeee_xxxx_tttt_aaaa_ffff_tttt_eeee_rrrr_llll_((((_v_a_l_u_e_1_,,,, _v_a_l_u_e_2_)))) is not. The
  152.      underflow and inexact exceptions are signalled when _nnnn_eeee_xxxx_tttt_aaaa_ffff_tttt_eeee_rrrr_((((_v_a_l_u_e_1_,,,,
  153.      _v_a_l_u_e_2_)))) lies strictly between +_2**-1022 or _nnnn_eeee_xxxx_tttt_aaaa_ffff_tttt_eeee_rrrr_llll_((((_v_a_l_u_e_1_,,,, _v_a_l_u_e_2_))))
  154.      lies strictly between +_2**-916.  In these cases _eeee_rrrr_rrrr_nnnn_oooo is also set to
  155.      _EEEE_RRRR_AAAA_NNNN_GGGG_EEEE.
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  195.                                                                         PPPPaaaaggggeeee 3333
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