foxBMS  1.4.0
The foxBMS Battery Management System API Documentation
foxmath.c
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41 
42 /**
43  * @file foxmath.c
44  * @author foxBMS Team
45  * @date 2018-01-18 (date of creation)
46  * @updated 2022-07-28 (date of last update)
47  * @version v1.4.0
48  * @ingroup DRIVERS
49  * @prefix MATH
50  *
51  * @brief mathlib function implementations
52  *
53  */
54 
55 /*========== Includes =======================================================*/
56 #include "foxmath.h"
57 
58 /*========== Macros and Definitions =========================================*/
59 /** shift one byte (8 positions) */
60 #define SHIFT_ONE_BYTE (8u)
61 
62 /** shift two bytes (16 positions) */
63 #define SHIFT_TWO_BYTES (16u)
64 
65 /** shift four bytes (32 positions) */
66 #define SHIFT_FOUR_BYTES (32u)
67 
68 /*========== Static Constant and Variable Definitions =======================*/
69 
70 /*========== Extern Constant and Variable Definitions =======================*/
71 
72 /*========== Static Function Prototypes =====================================*/
73 
74 /*========== Static Function Implementations ================================*/
75 
76 /*========== Extern Function Implementations ================================*/
77 
78 /* AXIVION Disable Style Generic-MissingParameterAssert: If not specified otherwise, functions in this lib are
79  designed to take full range input. No assert needed. */
80 
81 extern void MATH_StartupSelfTest(void) {
82  FAS_ASSERT(MATH_AbsInt64_t(INT64_MIN) == INT64_MAX);
83  FAS_ASSERT(MATH_AbsInt32_t(INT32_MIN) == INT32_MAX);
84 }
85 
87  const float x1,
88  const float y1,
89  const float x2,
90  const float y2,
91  const float x_interpolate) {
92  float slope = 0.0f;
93 
94  if (fabsf(x1 - x2) >= FLT_EPSILON) {
95  /* Calculate slope */
96  slope = (y2 - y1) / (x2 - x1);
97  }
98  /* In the case that the if clause is not entered (x values are identical)
99  * -> no interpolation possible: return y1 value
100  * -> slope takes initialization value of 0.0f
101  */
102 
103  /* Interpolate starting from x1/y1 */
104  float y_interpolate = y1 + (slope * (x_interpolate - x1));
105 
106  return y_interpolate;
107 }
108 
109 extern uint16_t MATH_SwapBytesUint16_t(const uint16_t val) {
110  return (val << SHIFT_ONE_BYTE) | (val >> SHIFT_ONE_BYTE);
111 }
112 
113 extern uint32_t MATH_SwapBytesUint32_t(const uint32_t val) {
114  const uint32_t alternating2PatternStartFF = 0xFF00FF00u;
115  const uint32_t alternating2PatternStart00 = 0x00FF00FFu;
116  const uint32_t intermediate = ((val << SHIFT_ONE_BYTE) & alternating2PatternStartFF) |
117  ((val >> SHIFT_ONE_BYTE) & alternating2PatternStart00);
118  return (intermediate << SHIFT_TWO_BYTES) | (intermediate >> SHIFT_TWO_BYTES);
119 }
120 
121 extern uint64_t MATH_SwapBytesUint64_t(const uint64_t val) {
122  const uint64_t alternating2PatternStartFF = 0xFF00FF00FF00FF00uLL;
123  const uint64_t alternating2PatternStart00 = 0x00FF00FF00FF00FFuLL;
124  const uint64_t alternating4PatternStartFFFF = 0xFFFF0000FFFF0000uLL;
125  const uint64_t alternating4PatternStart0000 = 0x0000FFFF0000FFFFuLL;
126 
127  uint64_t intermediate = ((val << SHIFT_ONE_BYTE) & alternating2PatternStartFF) |
128  ((val >> SHIFT_ONE_BYTE) & alternating2PatternStart00);
129  intermediate = ((intermediate << SHIFT_TWO_BYTES) & alternating4PatternStartFFFF) |
130  ((intermediate >> SHIFT_TWO_BYTES) & alternating4PatternStart0000);
131  return (intermediate << SHIFT_FOUR_BYTES) | (intermediate >> SHIFT_FOUR_BYTES);
132 }
133 
134 extern float MATH_MinimumOfTwoFloats(const float value1, const float value2) {
135  return fminf(value1, value2);
136 }
137 
138 extern uint8_t MATH_MinimumOfTwoUint8_t(const uint8_t value1, const uint8_t value2) {
139  uint8_t returnvalue = value1;
140  if (returnvalue > value2) {
141  returnvalue = value2;
142  }
143  return returnvalue;
144 }
145 
146 extern uint16_t MATH_MinimumOfTwoUint16_t(const uint16_t value1, const uint16_t value2) {
147  uint16_t returnvalue = value1;
148  if (returnvalue > value2) {
149  returnvalue = value2;
150  }
151  return returnvalue;
152 }
153 
154 extern int32_t MATH_AbsInt32_t(const int32_t value) {
155  int32_t absValue = INT32_MAX;
156  if (value != INT32_MIN) {
157  absValue = labs(value);
158  }
159  return absValue;
160 }
161 
162 extern int64_t MATH_AbsInt64_t(const int64_t value) {
163  int64_t absValue = INT64_MAX;
164  if (value != INT64_MIN) {
165  absValue = llabs(value);
166  }
167  return absValue;
168 }
169 
170 /* AXIVION Enable Style Generic-MissingParameterAssert: */
171 
172 /*========== Externalized Static Function Implementations (Unit Test) =======*/
#define FAS_ASSERT(x)
Assertion macro that asserts that x is true.
Definition: fassert.h:252
int32_t MATH_AbsInt32_t(const int32_t value)
Returns the absolute value of passed int32_t value.
Definition: foxmath.c:154
float MATH_LinearInterpolation(const float x1, const float y1, const float x2, const float y2, const float x_interpolate)
Linear inter-/extrapolates a third point according to two given points.
Definition: foxmath.c:86
uint16_t MATH_SwapBytesUint16_t(const uint16_t val)
Swap bytes of uint16_t value.
Definition: foxmath.c:109
int64_t MATH_AbsInt64_t(const int64_t value)
Returns the absolute value of passed int64_t value.
Definition: foxmath.c:162
uint16_t MATH_MinimumOfTwoUint16_t(const uint16_t value1, const uint16_t value2)
Returns the minimum of the passed uint16_t values.
Definition: foxmath.c:146
#define SHIFT_TWO_BYTES
Definition: foxmath.c:63
#define SHIFT_ONE_BYTE
Definition: foxmath.c:60
#define SHIFT_FOUR_BYTES
Definition: foxmath.c:66
uint32_t MATH_SwapBytesUint32_t(const uint32_t val)
Swap bytes of uint32_t value.
Definition: foxmath.c:113
void MATH_StartupSelfTest(void)
: self test for math functions that can be called at startup
Definition: foxmath.c:81
uint8_t MATH_MinimumOfTwoUint8_t(const uint8_t value1, const uint8_t value2)
Returns the minimum of the passed uint8_t values.
Definition: foxmath.c:138
float MATH_MinimumOfTwoFloats(const float value1, const float value2)
Returns the minimum of the passed float values.
Definition: foxmath.c:134
uint64_t MATH_SwapBytesUint64_t(const uint64_t val)
Swap bytes of uint64_t value.
Definition: foxmath.c:121
math library for often used math functions