ceph/src/dpdk/lib/librte_sched/rte_approx.h

   1 /*-
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  33
  34 #ifndef __INCLUDE_RTE_APPROX_H__
  35 #define __INCLUDE_RTE_APPROX_H__
  36
  37 #ifdef __cplusplus
  38 extern "C" {
  39 #endif
  40
  41 /**
  42  * @file
  43  * RTE Rational Approximation
  44  *
  45  * Given a rational number alpha with 0 < alpha < 1 and a precision d, the goal
  46  * is to find positive integers p, q such that alpha - d < p/q < alpha + d, and
  47  * q is minimal.
  48  *
  49  ***/
  50
  51 #include <stdint.h>
  52
  53 /**
  54  * Find best rational approximation
  55  *
  56  * @param alpha
  57  *   Rational number to approximate
  58  * @param d
  59  *   Precision for the rational approximation
  60  * @param p
  61  *   Pointer to pre-allocated space where the numerator of the rational
  62  *   approximation will be stored when operation is successful
  63  * @param q
  64  *   Pointer to pre-allocated space where the denominator of the rational
  65  *   approximation will be stored when operation is successful
  66  * @return
  67  *   0 upon success, error code otherwise
  68  */
  69 int rte_approx(double alpha, double d, uint32_t *p, uint32_t *q);
  70
  71 #ifdef __cplusplus
  72 }
  73 #endif
  74
  75 #endif /* __INCLUDE_RTE_APPROX_H__ */