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Copyright(c) 2019 by Aerospace C.Power (Chongqing) Microelectronics. ALL RIGHTS RESERVED.

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be copied by any method or incorporated into another program without
the express written consent of Aerospace C.Power. This Information or any portion
thereof remains the property of Aerospace C.Power. The Information contained herein
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****************************************************************************/

#include "math_log10.h"

const math_log10_tbl_t log10_tbl[] = {
    {0.0,     1         },
    {0.2,     2         },
    {0.4,     3         },
    {0.6,     4         },
    {0.7,     5         },
    {0.8,     6         },
    {0.9,     8         },
    {1.0,     10        },
    {1.1,     13        },
    {1.2,     16        },
    {1.3,     20        },
    {1.4,     25        },
    {1.5,     32        },
    {1.6,     40        },
    {1.7,     50        },
    {1.8,     63        },
    {1.9,     79        },
    {2.0,     100       },
    {2.1,     126       },
    {2.2,     158       },
    {2.3,     200       },
    {2.4,     251       },
    {2.5,     316       },
    {2.6,     398       },
    {2.7,     501       },
    {2.8,     631       },
    {2.9,     794       },
    {3.0,     1000      },
    {3.1,     1259      },
    {3.2,     1585      },
    {3.3,     1995      },
    {3.4,     2512      },
    {3.5,     3162      },
    {3.6,     3981      },
    {3.7,     5012      },
    {3.8,     6310      },
    {3.9,     7943      },
    {4.0,     10000     },
    {4.1,     12589     },
    {4.2,     15849     },
    {4.3,     19953     },
    {4.4,     25119     },
    {4.5,     31623     },
    {4.6,     39811     },
    {4.7,     50119     },
    {4.8,     63096     },
    {4.9,     79433     },
    {5.0,     100000    },
    {5.1,     125893    },
    {5.2,     158489    },
    {5.3,     199526    },
    {5.4,     251189    },
    {5.5,     316228    },
    {5.6,     398107    },
    {5.7,     501187    },
    {5.8,     630957    },
    {5.9,     794328    },
    {6.0,     1000000   },
    {6.1,     1258925   },
    {6.2,     1584893   },
    {6.3,     1995262   },
    {6.4,     2511886   },
    {6.5,     3162277   },
    {6.6,     3981071   },
    {6.7,     5011872   },
    {6.8,     6309573   },
    {6.9,     7943282   },
    {7.0,     10000000  },
    {7.1,     12589254  },
    {7.2,     15848931  },
    {7.3,     19952623  },
    {7.4,     25118864  },
    {7.5,     31622776  },
    {7.6,     39810717  },
    {7.7,     50118723  },
    {7.8,     63095734  },
    {7.9,     79432823  },
    {8.0,     100000000 },
    {8.1,     125892541 },
    {8.2,     158489319 },
    {8.3,     199526231 },
    {8.4,     251188643 },
    {8.5,     316227766 },
    {8.6,     398107170 },
    {8.7,     501187233 },
    {8.8,     630957344 },
    {8.9,     794328234 },
    {9.0,     1000000000},
    {9.1,     1258925411},
    {9.2,     1584893192},
    {9.3,     1995262314},
    {9.4,     2511886431},
    {9.5,     3162277660},
    {9.6,     3981071705},
    /* the maximum value of uint32 type is 4294967295 */
    {9.7,     5011872336},
    {9.8,     6309573444},
    {9.9,     7943282347},
    {10.0,    10000000000},
    {11.0,    100000000000},
    {12.0,    1000000000000},
    {13.0,    10000000000000},
    {14.0,    100000000000000},
    {15.0,    1000000000000000},
    {16.0,    10000000000000000},
    {17.0,    100000000000000000},
    {18.0,    1000000000000000000},
    //{19.0,    10000000000000000000}, /* uint64_t max */
};

float mlog10(uint64_t raw_data)
{
    uint32_t i;
    if(raw_data <= log10_tbl[0].raw_data){
        return log10_tbl[0].log10_val;
    }

    for(i = 1; i < sizeof(log10_tbl)/sizeof(math_log10_tbl_t); i++)
    {
        if(raw_data == log10_tbl[i].raw_data){
            return log10_tbl[i].log10_val;
        }
        else if(raw_data > log10_tbl[i-1].raw_data && \
            raw_data < log10_tbl[i].raw_data){
            return log10_tbl[i-1].log10_val;
        }
    }

    return log10_tbl[i-1].log10_val;
}