[301] | 1 | // ----------------------------------------------------------------------- |
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| 2 | // getStats.cc: Basic functions to calculate statistical parameters |
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| 3 | // such as mean, median, rms, madfm, min, max. |
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| 4 | // ----------------------------------------------------------------------- |
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| 5 | // Copyright (C) 2006, Matthew Whiting, ATNF |
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| 6 | // |
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| 7 | // This program is free software; you can redistribute it and/or modify it |
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| 8 | // under the terms of the GNU General Public License as published by the |
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| 9 | // Free Software Foundation; either version 2 of the License, or (at your |
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| 10 | // option) any later version. |
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| 11 | // |
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| 12 | // Duchamp is distributed in the hope that it will be useful, but WITHOUT |
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| 13 | // ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
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| 14 | // FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
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| 15 | // for more details. |
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| 16 | // |
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| 17 | // You should have received a copy of the GNU General Public License |
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| 18 | // along with Duchamp; if not, write to the Free Software Foundation, |
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| 19 | // Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA |
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| 20 | // |
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| 21 | // Correspondence concerning Duchamp may be directed to: |
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| 22 | // Internet email: Matthew.Whiting [at] atnf.csiro.au |
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| 23 | // Postal address: Dr. Matthew Whiting |
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| 24 | // Australia Telescope National Facility, CSIRO |
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| 25 | // PO Box 76 |
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| 26 | // Epping NSW 1710 |
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| 27 | // AUSTRALIA |
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| 28 | // ----------------------------------------------------------------------- |
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[3] | 29 | #include <iostream> |
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[204] | 30 | #include <algorithm> |
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[3] | 31 | #include <math.h> |
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[393] | 32 | #include <duchamp/Utils/utils.hh> |
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[3] | 33 | |
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[848] | 34 | template <class T> float findMean(T *array, size_t size) |
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[70] | 35 | { |
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[528] | 36 | /// @details |
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| 37 | /// Find the mean of an array of numbers. Type independent. |
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| 38 | /// \param array The array of numbers. |
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| 39 | /// \param size The length of the array. |
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| 40 | /// \return The mean value of the array, returned as a float |
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[848] | 41 | double mean = 0; |
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| 42 | for(size_t i=0;i<size;i++) mean += double(array[i]); |
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| 43 | if(size>0) |
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| 44 | mean /= double(size); |
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[653] | 45 | return float(mean); |
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[53] | 46 | } |
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[848] | 47 | template float findMean<int>(int *array, size_t size); |
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| 48 | template float findMean<long>(long *array, size_t size); |
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| 49 | template float findMean<float>(float *array, size_t size); |
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| 50 | template float findMean<double>(double *array, size_t size); |
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[190] | 51 | //-------------------------------------------------------------------- |
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[53] | 52 | |
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[848] | 53 | template <class T> float findMean(T *array, bool *mask, size_t size) |
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[53] | 54 | { |
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[528] | 55 | /// @details |
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[848] | 56 | /// Find the mean of an array of numbers. Type independent. |
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[528] | 57 | /// \param array The array of numbers. |
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[848] | 58 | /// \param mask An array of the same length that says whether to |
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| 59 | /// include each member of the array in the calculations. Only use |
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| 60 | /// values where mask=true. |
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[528] | 61 | /// \param size The length of the array. |
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[848] | 62 | /// \return The mean value of the array, returned as a float |
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| 63 | double mean = 0.; |
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| 64 | int ct=0; |
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| 65 | for(size_t i=0;i<size;i++){ |
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| 66 | if(mask[i]){ |
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| 67 | mean += double(array[i]); |
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| 68 | ct++; |
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| 69 | } |
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[646] | 70 | } |
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[848] | 71 | if(ct>0) mean /= double(ct); |
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| 72 | return float(mean); |
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[53] | 73 | } |
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[848] | 74 | template float findMean<int>(int *array, bool *mask, size_t size); |
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| 75 | template float findMean<long>(long *array, bool *mask, size_t size); |
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| 76 | template float findMean<float>(float *array, bool *mask, size_t size); |
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| 77 | template float findMean<double>(double *array, bool *mask, size_t size); |
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[190] | 78 | //-------------------------------------------------------------------- |
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[53] | 79 | |
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[848] | 80 | template <class T> float findStddev(T *array, size_t size) |
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[53] | 81 | { |
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[848] | 82 | /// @details Find the rms or standard deviation of an array of |
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| 83 | /// numbers. Type independent. Calculated by iterating only once, |
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| 84 | /// using \sum x and \sum x^2 (no call to findMean) |
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[528] | 85 | /// \param array The array of numbers. |
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| 86 | /// \param size The length of the array. |
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[848] | 87 | /// \return The rms value of the array, returned as a float |
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[646] | 88 | |
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[848] | 89 | // double mean = double(findMean(array,size)); |
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| 90 | // double stddev = (double(array[0])-mean) * (double(array[0])-mean); |
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| 91 | // for(size_t i=1;i<size;i++) stddev += (double(array[i])-mean)*(double(array[i])-mean); |
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| 92 | // double stddev = stddev/double(size-1)); |
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[190] | 93 | |
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[848] | 94 | T sumx=0,sumxx=0; |
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| 95 | double stddev=0; |
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| 96 | for(size_t i=0;i<size;i++){ |
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| 97 | sumx += array[i]; |
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| 98 | sumxx += (array[i]*array[i]); |
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[756] | 99 | } |
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[848] | 100 | if(size>0) |
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| 101 | stddev = sqrt(double(sumxx)/double(size) - double(sumx*sumx)/double(size*size)); |
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| 102 | return float(stddev); |
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[756] | 103 | } |
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[848] | 104 | template float findStddev<int>(int *array, size_t size); |
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| 105 | template float findStddev<long>(long *array, size_t size); |
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| 106 | template float findStddev<float>(float *array, size_t size); |
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| 107 | template float findStddev<double>(double *array, size_t size); |
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[756] | 108 | //-------------------------------------------------------------------- |
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| 109 | |
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[848] | 110 | template <class T> float findStddev(T *array, bool *mask, size_t size) |
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[3] | 111 | { |
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[848] | 112 | /// @details Find the rms or standard deviation of an array of |
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| 113 | /// numbers. Type independent. Calculated by iterating only once, |
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| 114 | /// using \sum x and \sum x^2 (no call to findMean) |
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[528] | 115 | /// \param array The array of numbers. |
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| 116 | /// \param mask An array of the same length that says whether to |
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| 117 | /// include each member of the array in the calculations. Only use |
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| 118 | /// values where mask=true. |
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[848] | 119 | /// \param size The length of the array. |
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| 120 | /// \return The rms value of the array, returned as a float |
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[528] | 121 | |
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[848] | 122 | T sumx=0,sumxx=0; |
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| 123 | double stddev=0; |
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| 124 | int ct=0; |
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| 125 | for(size_t i=0;i<size;i++){ |
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| 126 | if(mask[i]){ |
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| 127 | sumx += array[i]; |
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| 128 | sumxx += (array[i]*array[i]); |
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| 129 | ct++; |
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| 130 | } |
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[190] | 131 | } |
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[848] | 132 | if(ct>0) |
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| 133 | stddev = sqrt(double(sumxx)/double(ct) - double(sumx*sumx)/double(ct*ct)); |
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| 134 | return float(stddev); |
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[3] | 135 | } |
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[848] | 136 | template float findStddev<int>(int *array, bool *mask, size_t size); |
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| 137 | template float findStddev<long>(long *array, bool *mask, size_t size); |
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| 138 | template float findStddev<float>(float *array, bool *mask, size_t size); |
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| 139 | template float findStddev<double>(double *array, bool *mask, size_t size); |
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[190] | 140 | //-------------------------------------------------------------------- |
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[3] | 141 | |
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[848] | 142 | template <class T> void findNormalStats(T *array, size_t size, |
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[190] | 143 | float &mean, float &stddev) |
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[3] | 144 | { |
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[528] | 145 | /// @details |
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| 146 | /// Find the mean and rms or standard deviation of an array of |
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| 147 | /// numbers. Type independent. |
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| 148 | /// |
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| 149 | /// \param array The array of numbers. |
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| 150 | /// \param size The length of the array. |
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| 151 | /// \param mean The mean value of the array, returned as a float. |
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| 152 | /// \param stddev The rms or standard deviation of the array, |
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| 153 | /// returned as a float. |
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| 154 | |
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[190] | 155 | if(size==0){ |
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| 156 | std::cerr << "Error in findNormalStats: zero sized array!\n"; |
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| 157 | return; |
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| 158 | } |
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[3] | 159 | mean = array[0]; |
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[848] | 160 | for(size_t i=1;i<size;i++){ |
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[3] | 161 | mean += array[i]; |
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| 162 | } |
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| 163 | mean /= float(size); |
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| 164 | |
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[79] | 165 | stddev = (array[0]-mean) * (array[0]-mean); |
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[848] | 166 | for(size_t i=1;i<size;i++) stddev += (array[i]-mean)*(array[i]-mean); |
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[79] | 167 | stddev = sqrt(stddev/float(size-1)); |
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[3] | 168 | |
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| 169 | } |
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[848] | 170 | template void findNormalStats<int>(int *array, size_t size, |
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[222] | 171 | float &mean, float &stddev); |
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[848] | 172 | template void findNormalStats<long>(long *array, size_t size, |
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[222] | 173 | float &mean, float &stddev); |
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[848] | 174 | template void findNormalStats<float>(float *array, size_t size, |
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[222] | 175 | float &mean, float &stddev); |
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[848] | 176 | template void findNormalStats<double>(double *array, size_t size, |
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[222] | 177 | float &mean, float &stddev); |
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[190] | 178 | //-------------------------------------------------------------------- |
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[3] | 179 | |
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[848] | 180 | template <class T> void findNormalStats(T *array, size_t size, bool *mask, |
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[190] | 181 | float &mean, float &stddev) |
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[70] | 182 | { |
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[528] | 183 | /// @details |
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| 184 | /// Find the mean and rms or standard deviation of a subset of an |
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| 185 | /// array of numbers. The subset is defined by an array of bool |
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| 186 | /// variables. Type independent. |
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| 187 | /// |
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| 188 | /// \param array The array of numbers. |
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| 189 | /// \param size The length of the array. |
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| 190 | /// \param mask An array of the same length that says whether to |
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| 191 | /// include each member of the array in the calculations. Only look |
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| 192 | /// at values where mask=true. |
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| 193 | /// \param mean The mean value of the array, returned as a float. |
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| 194 | /// \param stddev The rms or standard deviation of the array, |
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| 195 | /// returned as a float. |
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| 196 | |
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[190] | 197 | int goodSize=0; |
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[848] | 198 | for(size_t i=0;i<size;i++) if(mask[i]) goodSize++; |
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[190] | 199 | if(goodSize==0){ |
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| 200 | std::cerr << "Error in findNormalStats: no good values!\n"; |
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| 201 | return; |
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| 202 | } |
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| 203 | int start=0; |
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[275] | 204 | while(!mask[start]){start++;} |
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[190] | 205 | mean = array[start]; |
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[848] | 206 | for(size_t i=start+1;i<size;i++){ |
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[275] | 207 | if(mask[i]) mean += array[i]; |
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[190] | 208 | } |
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| 209 | mean /= float(goodSize); |
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[70] | 210 | |
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[190] | 211 | stddev = (array[start]-mean) * (array[start]-mean); |
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[848] | 212 | for(size_t i=1;i<size;i++){ |
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[275] | 213 | if(mask[i]) stddev += (array[i]-mean)*(array[i]-mean); |
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[190] | 214 | } |
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| 215 | stddev = sqrt(stddev/float(goodSize-1)); |
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| 216 | |
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| 217 | } |
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[848] | 218 | template void findNormalStats<int>(int *array, size_t size, bool *mask, |
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[222] | 219 | float &mean, float &stddev); |
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[848] | 220 | template void findNormalStats<long>(long *array, size_t size, bool *mask, |
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[222] | 221 | float &mean, float &stddev); |
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[848] | 222 | template void findNormalStats<float>(float *array, size_t size, bool *mask, |
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[222] | 223 | float &mean, float &stddev); |
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[848] | 224 | template void findNormalStats<double>(double *array, size_t size, bool *mask, |
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[222] | 225 | float &mean, float &stddev); |
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[848] | 226 | //-------------------------------------------------------------------- |
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[275] | 227 | |
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[848] | 228 | template <class T> void findNormalStatsDiff(T *first, T *second, size_t size, |
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| 229 | float &mean, float &stddev) |
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[275] | 230 | { |
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[528] | 231 | /// @details |
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[848] | 232 | /// Find the mean and rms or standard deviation of the difference between two arrays of |
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| 233 | /// numbers. The difference is defined as first - second. Type independent. |
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[528] | 234 | /// |
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[848] | 235 | /// \param first The first array |
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| 236 | /// \param second The second array |
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[528] | 237 | /// \param size The length of the array. |
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| 238 | /// \param mean The mean value of the array, returned as a float. |
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| 239 | /// \param stddev The rms or standard deviation of the array, |
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| 240 | /// returned as a float. |
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| 241 | |
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[275] | 242 | if(size==0){ |
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[848] | 243 | std::cerr << "Error in findNormalStats: zero sized array!\n"; |
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[275] | 244 | return; |
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| 245 | } |
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[848] | 246 | mean = first[0]-second[0]; |
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| 247 | for(size_t i=1;i<size;i++){ |
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| 248 | mean += (first[i]-second[i]); |
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| 249 | } |
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| 250 | mean /= float(size); |
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[275] | 251 | |
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[848] | 252 | stddev = (first[0]-second[0]-mean) * (first[0]-second[0]-mean); |
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| 253 | for(size_t i=1;i<size;i++) stddev += (first[i]-second[i]-mean)*(first[i]-second[i]-mean); |
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| 254 | stddev = sqrt(stddev/float(size-1)); |
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[275] | 255 | |
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| 256 | } |
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[848] | 257 | template void findNormalStatsDiff<int>(int *first, int *second, size_t size, |
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| 258 | float &mean, float &stddev); |
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| 259 | template void findNormalStatsDiff<long>(long *first, long *second, size_t size, |
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| 260 | float &mean, float &stddev); |
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| 261 | template void findNormalStatsDiff<float>(float *first, float *second, size_t size, |
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| 262 | float &mean, float &stddev); |
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| 263 | template void findNormalStatsDiff<double>(double *first, double *second, size_t size, |
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| 264 | float &mean, float &stddev); |
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[275] | 265 | //-------------------------------------------------------------------- |
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| 266 | |
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[848] | 267 | template <class T> void findNormalStatsDiff(T *first, T *second, size_t size, bool *mask, |
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| 268 | float &mean, float &stddev) |
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[275] | 269 | { |
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[848] | 270 | /// @details Find the mean and rms or standard deviation of the |
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| 271 | /// difference between two arrays of numbers, where some elements |
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| 272 | /// are masked out. The mask is defined by an array of bool |
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| 273 | /// variables, and the difference is defined as first - second. Type |
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| 274 | /// independent. |
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[528] | 275 | /// |
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[848] | 276 | /// \param first The first array |
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| 277 | /// \param second The second array |
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[528] | 278 | /// \param size The length of the array. |
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| 279 | /// \param mask An array of the same length that says whether to |
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| 280 | /// include each member of the array in the calculations. Only look |
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| 281 | /// at values where mask=true. |
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| 282 | /// \param mean The mean value of the array, returned as a float. |
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| 283 | /// \param stddev The rms or standard deviation of the array, |
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| 284 | /// returned as a float. |
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| 285 | |
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[275] | 286 | int goodSize=0; |
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[848] | 287 | for(size_t i=0;i<size;i++) if(mask[i]) goodSize++; |
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[275] | 288 | if(goodSize==0){ |
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[848] | 289 | std::cerr << "Error in findNormalStats: no good values!\n"; |
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[275] | 290 | return; |
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| 291 | } |
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[848] | 292 | int start=0; |
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| 293 | while(!mask[start]){start++;} |
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| 294 | mean = first[start]-second[start]; |
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| 295 | for(size_t i=start+1;i<size;i++){ |
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| 296 | if(mask[i]) mean += (first[i]-second[i]); |
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| 297 | } |
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| 298 | mean /= float(goodSize); |
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[275] | 299 | |
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[848] | 300 | stddev = (first[start]-second[start]-mean) * (first[start]-second[start]-mean); |
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| 301 | for(size_t i=1;i<size;i++){ |
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| 302 | if(mask[i]) stddev += (first[i]-second[i]-mean)*(first[i]-second[i]-mean); |
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| 303 | } |
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| 304 | stddev = sqrt(stddev/float(goodSize-1)); |
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[275] | 305 | |
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| 306 | } |
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[848] | 307 | template void findNormalStatsDiff<int>(int *first, int *second, size_t size, bool *mask, |
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| 308 | float &mean, float &stddev); |
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| 309 | template void findNormalStatsDiff<long>(long *first, long *second, size_t size, bool *mask, |
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| 310 | float &mean, float &stddev); |
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| 311 | template void findNormalStatsDiff<float>(float *first, float *second, size_t size, bool *mask, |
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| 312 | float &mean, float &stddev); |
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| 313 | template void findNormalStatsDiff<double>(double *first, double *second, size_t size, bool *mask, |
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| 314 | float &mean, float &stddev); |
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[275] | 315 | //-------------------------------------------------------------------- |
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