Provides routines to determine the top-level and base-level of data. More...
#include "mdb.h"Go to the source code of this file.
Macros | |
| #define | DEFAULT_BINFACTOR 0.05 |
| #define | DEFAULT_SIGMAS 2 |
Functions | |
| long | findTopBaseLevels (double *top, double *base, double *data, int64_t points, long bins, double sigmasRequired) |
| Finds the top-level and base-level of a dataset. | |
| int64_t | findCrossingPoint (int64_t start, double *data, int64_t points, double level, long direction, double *indepData, double *location) |
| Finds the crossing point in the data where the data crosses a specified level. | |
Detailed Description
Provides routines to determine the top-level and base-level of data.
This file contains functions to find the top-level and base-level of a dataset, as well as to identify crossing points within the data. The routines utilize histogram binning and statistical analysis to compute these levels.
- Copyright
- (c) 2002 The University of Chicago, as Operator of Argonne National Laboratory.
- (c) 2002 The Regents of the University of California, as Operator of Los Alamos National Laboratory.
- License
- This file is distributed under the terms of the Software License Agreement found in the file LICENSE included with this distribution.
Definition in file topbase.c.
Macro Definition Documentation
◆ DEFAULT_BINFACTOR
◆ DEFAULT_SIGMAS
Function Documentation
◆ findCrossingPoint()
| int64_t findCrossingPoint | ( | int64_t | start, |
| double * | data, | ||
| int64_t | points, | ||
| double | level, | ||
| long | direction, | ||
| double * | indepData, | ||
| double * | location ) |
Finds the crossing point in the data where the data crosses a specified level.
- Parameters
-
start The starting index to search for the crossing point. data Pointer to the array of data points. points Number of data points in the array. level The level at which to find the crossing point. direction The direction of crossing (positive for upward, negative for downward). indepData Pointer to the independent data array corresponding to the data points. Can be NULL. location Pointer to store the interpolated location of the crossing point. Can be NULL.
- Returns
- The index of the crossing point on success,
- -1 if no crossing is found or if input parameters are invalid.
Definition at line 118 of file topbase.c.
119 {
120 double diff;
121 int64_t i;
122 long transitionPossible;
123
124 if (start < 0 || start > (points - 1))
125 return -1;
126 transitionPossible = 0;
127 for (i = start; i < points; i++) {
128 diff = direction * (data[i] - level);
129 if (diff <= 0)
130 transitionPossible = 1;
131 if (diff > 0 && transitionPossible)
132 break;
133 }
134 if (i == points)
135 return -1;
136 if (!indepData || !location)
137 return i;
138 if (i == 0 || data[i] == data[i - 1]) {
139 *location = indepData[i];
140 return i;
141 }
142 *location = indepData[i - 1] + (indepData[i] - indepData[i - 1]) / (data[i] - data[i - 1]) * (level - data[i - 1]);
143 return i;
144}
◆ findTopBaseLevels()
| long findTopBaseLevels | ( | double * | top, |
| double * | base, | ||
| double * | data, | ||
| int64_t | points, | ||
| long | bins, | ||
| double | sigmasRequired ) |
Finds the top-level and base-level of a dataset.
- Parameters
-
top Pointer to store the computed top-level value. base Pointer to store the computed base-level value. data Pointer to the array of data points. points Number of data points in the array. bins Number of bins to use for histogram computation. If <= 0, a default bin factor is applied. sigmasRequired Number of standard deviations required for determining significant histogram peaks.
- Returns
- Returns 1 on success, 0 on failure.
Definition at line 36 of file topbase.c.
37 {
38 long binned, iMaximum, i;
39 static long maxBins = 0;
40 static double *histogram = NULL;
41 double min, max, midpoint, maxHistogram, meanBinned;
42 double lower, upper, delta;
43
44 if (bins <= 0)
45 bins = DEFAULT_BINFACTOR * points;
46 if (sigmasRequired <= 0)
47 sigmasRequired = DEFAULT_SIGMAS;
48 if (points < 2)
49 return 0;
50
51 if (bins > maxBins)
53
55 return 0;
56
57 *base = min;
58 *top = max;
59 midpoint = (min + max) / 2;
60 if (points < 10)
61 return 1;
62
63 delta = (midpoint - min) / (bins - 1);
64 lower = min - delta / 2;
65 upper = midpoint + delta / 2;
67 maxHistogram = 0;
68 iMaximum = -1;
69 for (i = 0; i < bins; i++) {
70 if (maxHistogram < histogram[i]) {
71 iMaximum = i;
72 maxHistogram = histogram[i];
73 }
74 }
75 meanBinned = ((double)binned) / bins;
76 if ((maxHistogram > 1) && (maxHistogram > (meanBinned + sigmasRequired * sqrt(meanBinned))))
77 *base = lower + (iMaximum + 0.5) * ((upper - lower) / bins);
78 }
79
80 delta = (max - midpoint) / (bins - 1);
81 lower = midpoint - delta / 2;
82 upper = max + delta / 2;
84 maxHistogram = 0;
85 iMaximum = -1;
86 for (i = 0; i < bins; i++) {
87 if (maxHistogram < histogram[i]) {
88 iMaximum = i;
89 maxHistogram = histogram[i];
90 }
91 }
92 meanBinned = ((double)binned) / bins;
93 if ((maxHistogram > 1) && (maxHistogram > (meanBinned + sigmasRequired * sqrt(meanBinned))))
94 *top = lower + (iMaximum + 0.5) * ((upper - lower) / bins);
95 }
96
97 if (*top == *base) {
98 *base = min;
99 *top = max;
100 }
101 return 1;
102}
void * tmalloc(uint64_t size_of_block)
Allocates a memory block of the specified size with zero initialization.
Definition array.c:59
int find_min_max(double *min, double *max, double *list, int64_t n)
Finds the minimum and maximum values in a list of doubles.
Definition findMinMax.c:33
long make_histogram(double *hist, long n_bins, double lo, double hi, double *data, int64_t n_pts, long new_start)
Compiles a histogram from data points.
Definition makeHistogram.c:33
Generated by
1.12.0