include/histogram.h

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  38 /*! \file
  39  * \brief API for calculation of histograms with error estimates.
  40  *
  41  * The API is documented in more detail on a separate page:
  42  * \ref histograms
  43  *
  44  * The functions within this file can be used and developed independently of
  45  * the other parts of the library.
  46  * Other parts of the library do not reference these functions.
  47  */
  48 #ifndef HISTOGRAM_H
  49 #define HISTOGRAM_H
  50
  51 #include "typedefs.h"
  52
  53 #ifdef __cplusplus
  54 extern "C"
  55 {
  56 #endif
  57
  58 /** Type of histogram. */
  59 typedef enum
  60 {
  61     /*! \brief
  62      * Simple histogram.
  63      *
  64      * Use gmx_histogram_increment() or gmx_histogram_increment_bin()
  65      * to sample.
  66      */
  67     HIST_SIMPLE,
  68     /*! \brief
  69      * Weighted histogram where different points contribute different amounts.
  70      *
  71      * Use gmx_histogram_add() or gmx_histogram_add_to_bin() to sample.
  72      */
  73     HIST_WEIGHT,
  74     /*! \brief
  75      * Calculate averages within each bin.
  76      *
  77      * Use gmx_histogram_add_item() or gmx_histogram_add_item_to_bin() to sample.
  78      */
  79     HIST_BINAVER
  80 } e_histogram_t;
  81
  82 /** Whether bins are centered at integer values. */
  83 #define HIST_INTEGERBINS  1
  84 /** Whether the values outside the range should be included in the histogram. */
  85 #define HIST_ALL          2
  86 /** Whether the initialization used binwidths. */
  87 #define HIST_INITBW       128
  88
  89 /** Stores data for a histogram. */
  90 typedef struct gmx_histogram_t gmx_histogram_t;
  91
  92 /*! \name Initialization functions
  93  */
  94 /*@{*/
  95 /** Initialize calculation of a histogram. */
  96 int
  97 gmx_histogram_create(gmx_histogram_t **h, e_histogram_t type, int nbins);
  98 /** Initialize calculation of a histogram for a range. */
  99 int
 100 gmx_histogram_create_range(gmx_histogram_t **h, e_histogram_t type,
 101                            real start, real end, real binw, gmx_bool bIntegerBins);
 102 /** Clears the bins in the histogram. */
 103 void
 104 gmx_histogram_clear(gmx_histogram_t *h);
 105 /** Frees the memory allocated for a histogram. */
 106 void
 107 gmx_histogram_free(gmx_histogram_t *h);
 108 /** Sets histogram range using a starting point and a bin width. */
 109 int
 110 gmx_histogram_set_binwidth(gmx_histogram_t *h, real start, real binw);
 111 /** Sets histogram range using endpoint values. */
 112 int
 113 gmx_histogram_set_range(gmx_histogram_t *h, real start, real end);
 114 /** Sets histogram bins to center at integer values. */
 115 void
 116 gmx_histogram_set_integerbins(gmx_histogram_t *h, gmx_bool bIntegerBins);
 117 /** Sets histogram to include outlying values in the bins at the edges. */
 118 void
 119 gmx_histogram_set_all(gmx_histogram_t *h, gmx_bool bAll);
 120 /** Sets block size for histogram averaging. */
 121 int
 122 gmx_histogram_set_blocksize(gmx_histogram_t *h, int bsize);
 123 /** Sets output file for block histograms. */
 124 int
 125 gmx_histogram_set_block_output(gmx_histogram_t *h, FILE *fp);
 126 /*@}*/
 127
 128 /*! \name Access functions
 129  */
 130 /*@{*/
 131 /** Finds the histogram bin corresponding to a value. */
 132 int
 133 gmx_histogram_find_bin(gmx_histogram_t *h, real pos);
 134 /** Returns the number of bins in a histogram. */
 135 int
 136 gmx_histogram_get_nbins(gmx_histogram_t *h);
 137 /** Returns the bin width of a histogram. */
 138 real
 139 gmx_histogram_get_binwidth(gmx_histogram_t *h);
 140 /** Returns the value of the histogram at a certain position. */
 141 void
 142 gmx_histogram_get_value(gmx_histogram_t *h, real pos, double *val, double *err);
 143 /** Returns the value of the histogram in a certain bin. */
 144 void
 145 gmx_histogram_get_bin_value(gmx_histogram_t *h, int bin, double *val, double *err);
 146 /** Returns an array of values for the histogram. */
 147 double *
 148 gmx_histogram_get_values(gmx_histogram_t *h);
 149 /** Returns an array of error values for the histogram. */
 150 double *
 151 gmx_histogram_get_errors(gmx_histogram_t *h);
 152 /*@}*/
 153
 154 /*! \name Sampling functions
 155  */
 156 /*@{*/
 157 /** Increments the count in a histogram bin corresponding to \p pos. */
 158 void
 159 gmx_histogram_increment(gmx_histogram_t *h, real pos);
 160 /** Increments the count in a histogram bin. */
 161 void
 162 gmx_histogram_increment_bin(gmx_histogram_t *h, int bin);
 163
 164 /** Adds a value to a histogram bin corresponding to \p pos. */
 165 void
 166 gmx_histogram_add(gmx_histogram_t *h, real pos, double value);
 167 /** Adds a value to a histogram bin. */
 168 void
 169 gmx_histogram_add_to_bin(gmx_histogram_t *h, int bin, double value);
 170
 171 /** Adds a value to a histogram bin corresponding to \p pos. */
 172 void
 173 gmx_histogram_add_item(gmx_histogram_t *h, real pos, double value);
 174 /** Adds a value to a histogram bin. */
 175 void
 176 gmx_histogram_add_item_to_bin(gmx_histogram_t *h, int bin, double value);
 177
 178 /** Finishes histogram sampling for a frame. */
 179 void
 180 gmx_histogram_finish_frame(gmx_histogram_t *h);
 181 /** Normalizes a histogram. */
 182 void
 183 gmx_histogram_finish(gmx_histogram_t *h);
 184 /*@}*/
 185
 186
 187 /*! \name Post-processing functions
 188  */
 189 /*@{*/
 190 /** Creates a new histogram with double the binwidth. */
 191 void
 192 gmx_histogram_resample_dblbw(gmx_histogram_t **dest, gmx_histogram_t *src,
 193                              gmx_bool bIntegerBins);
 194 /** Makes a clone of a histogram. */
 195 void
 196 gmx_histogram_clone(gmx_histogram_t **dest, gmx_histogram_t *src);
 197 /** Normalizes a histogram to a probability distribution. */
 198 void
 199 gmx_histogram_normalize_prob(gmx_histogram_t *h);
 200 /** Scales a histogram with a custom normalization factor. */
 201 void
 202 gmx_histogram_scale(gmx_histogram_t *h, real norm);
 203 /** Scales a histogram with a custom non-uniform normalization factor. */
 204 void
 205 gmx_histogram_scale_vec(gmx_histogram_t *h, real norm[]);
 206 /** Writes a single histogram to a file. */
 207 void
 208 gmx_histogram_write(FILE *fp, gmx_histogram_t *h, gmx_bool bErrors);
 209 /** Writes a set of histograms to a file. */
 210 void
 211 gmx_histogram_write_array(FILE *fp, int n, gmx_histogram_t *h[],
 212                           gmx_bool bValue, gmx_bool bErrors);
 213 /** Writes a set of cumulative histograms to a file. */
 214 void
 215 gmx_histogram_write_cum_array(FILE *fp, int n, gmx_histogram_t *h[],
 216                               gmx_bool bValue, gmx_bool bErrors);
 217 /*@}*/
 218
 219 #ifdef __cplusplus
 220 }
 221 #endif
 222
 223 #endif