qpms/tiny_inlines.h

   1 /*! \file tiny_inlines.h
   2  * \brief Simple but frequently used inline functions and macros.
   3  */
   4 #ifndef TINY_INLINES_H
   5 #define TINY_INLINES_H
   6 #include <stdlib.h>
   7
   8 static inline int min1pow(int pow) { return (pow % 2) ? -1 : 1; }
   9
  10
  11 // This is useful for calculating spherical harmonics with negative m
  12 // if spharm-normalised legendre functions for positive m are available.
  13 // TODO: write a function that gets legendre buffer, m, n, and returns the correct spharm
  14 // and use it in the code (mainly translations.c, ewald.c).
  15 static inline int min1pow_m_neg(int m) {
  16         return (m < 0) ? min1pow(m) : 1;
  17 }
  18
  19
  20 #if 0
  21 #ifdef __GSL_SF_LEGENDRE_H__
  22 static inline complex double
  23 spharm_eval(gsl_sf_legendre_t P_normconv, int P_csphase, qpms_l_t l, qpms_m_t m, double P_n_abs_m, complex double exp_imf) {
  24
  25         return;
  26 }
  27 #endif
  28 #endif
  29
  30 // this has shitty precision:
  31 // static inline complex double ipow(int x) { return cpow(I, x); }
  32
  33 static inline complex double ipow(int x) {
  34   x = ((x % 4) + 4) % 4;
  35   switch(x) {
  36     case 0:
  37       return 1;
  38     case 1:
  39       return I;
  40     case 2:
  41       return -1;
  42     case 3:
  43       return -I;
  44     default:
  45       abort();
  46   }
  47 }
  48
  49 static inline int isq(int x) {return x * x;}
  50
  51 #ifndef MIN
  52 #define MIN(x, y) (((x) < (y)) ? (x) : (y))
  53 #endif
  54
  55 #ifndef MAX
  56 #define MAX(x, y) (((x) >= (y)) ? (x) : (y))
  57 #endif
  58
  59 #ifndef SQ
  60 #define SQ(x) ((x) * (x))
  61 #endif
  62
  63
  64 #endif // TINY_INLINES_H