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authorEthan Werner <mail@ethanwerner.com>2026-07-01 09:42:39 +0400
committerEthan Werner <mail@ethanwerner.com>2026-07-01 09:42:39 +0400
commit07e18043145f3d91c8ea7ec3ad41b3c905585277 (patch)
tree2bdeae46973f4bdfce263679a4008ac768011f28 /lib/shinohara_intensity_ratio.c
initial commit: ts time series analysis library v0.1.0
- 354 financial and mathematical time-series indicators - Uniform C11 API with consistent function signatures - 349 passing tests with -Werror - Static and shared library builds - pkg-config integration - Python bindings - Fuzzing and sanitizer support - Security hardening flags
Diffstat (limited to 'lib/shinohara_intensity_ratio.c')
-rw-r--r--lib/shinohara_intensity_ratio.c85
1 files changed, 85 insertions, 0 deletions
diff --git a/lib/shinohara_intensity_ratio.c b/lib/shinohara_intensity_ratio.c
new file mode 100644
index 0000000..fcdd364
--- /dev/null
+++ b/lib/shinohara_intensity_ratio.c
@@ -0,0 +1,85 @@
+// Shinohara Intensity Ratio
+//
+// shinohara_intensity_ratio
+//
+// Shinohara Intensity Ratio
+//
+//
+//
+// Inputs: 4
+// Outputs: 1
+// Constants: 1
+
+
+#include <stdlib.h>
+#include <math.h>
+#include "ts.h"
+
+typedef struct {
+ uint_t k;
+} ts_shinohara_intensity_ratio_params_t;
+
+ts_parameter_t const ts_shinohara_intensity_ratio_p = { .n_inputs = 4, .n_outputs = 1, .n_constants = 1, .params_size = sizeof(ts_shinohara_intensity_ratio_params_t) };
+
+uint_t ts_shinohara_intensity_ratio_offset( ts_constant_t const *c )
+{
+ ( void )c;
+ return ( c ? ((ts_shinohara_intensity_ratio_params_t *)c)->k > 0 ? ((ts_shinohara_intensity_ratio_params_t *)c)->k - 1 : 0 : 0 );
+}
+
+int ts_shinohara_intensity_ratio(
+ fp_t * const *y, uint_t y_n,
+ fp_t const * const *x, uint_t x_n,
+ uint_t n, ts_constant_t const *c
+)
+{
+ TS_PROLOGUE( ts_shinohara_intensity_ratio_p );
+ if ( !c ) return -1;
+ uint_t k = ((ts_shinohara_intensity_ratio_params_t *)c)->k;
+ if (k == 0 || n < k) return -1;
+
+ fp_t *intensity = calloc( n, sizeof( fp_t ) );
+ if ( !intensity ) return -1;
+
+ for( uint_t i = 0; i < n; ++i )
+ {
+ fp_t h = ts_h(x, i);
+ fp_t l = ts_l(x, i);
+ fp_t cl = ts_c(x, i);
+ fp_t o = ts_o(x, i);
+ fp_t range = h - l;
+
+ if( range == 0 )
+ {
+ intensity[i] = 0;
+ }
+ else if( cl > o )
+ {
+ intensity[i] = (h - cl) / range;
+ }
+ else
+ {
+ intensity[i] = (cl - l) / range;
+ }
+ }
+
+ for (uint_t j = 0; j < n && j < k - 1; ++j) y[0][j] = 0;
+ for( uint_t i = k - 1; i < n; ++i )
+ {
+ if( i == k - 1 )
+ {
+ fp_t sum = 0;
+ for( uint_t j = 0; j < k; ++j )
+ sum += intensity[j];
+ y[0][i] = sum / k;
+ }
+ else
+ {
+ y[0][i] = y[0][i-1] + (intensity[i] - intensity[i - k]) / k;
+ }
+ }
+
+ free( intensity );
+ return 0;
+}
+