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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/donchian_width.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/donchian_width.c')
-rw-r--r--lib/donchian_width.c56
1 files changed, 56 insertions, 0 deletions
diff --git a/lib/donchian_width.c b/lib/donchian_width.c
new file mode 100644
index 0000000..c69936f
--- /dev/null
+++ b/lib/donchian_width.c
@@ -0,0 +1,56 @@
+// Donchian Width
+//
+// donchian_width - DW
+//
+// Highest high - lowest low over k periods
+//
+// Inputs: 5 (OHLCV)
+// Outputs: 1 (Width)
+// Constants: 1 (period)
+
+#include <math.h>
+#include "ts.h"
+
+typedef struct {
+ uint_t k;
+} ts_donchian_width_params_t;
+
+ts_parameter_t const ts_donchian_width_p = { .n_inputs = 4, .n_outputs = 1, .n_constants = 1, .params_size = sizeof(ts_donchian_width_params_t) };
+
+uint_t ts_donchian_width_offset( ts_constant_t const *c )
+{
+ ( void )c;
+ return ( c ? ((ts_donchian_width_params_t *)c)->k > 0 ? ((ts_donchian_width_params_t *)c)->k - 1 : 0 : 0 );
+}
+
+int ts_donchian_width(
+ 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_donchian_width_p );
+ if ( !c ) return -1;
+ uint_t k = ((ts_donchian_width_params_t *)c)->k;
+ if (k == 0 || n < k) return -1;
+
+ for ( uint_t i = k - 1; i < n; ++i )
+ {
+ fp_t upper = ts_h( x, i - k + 1 );
+ fp_t lower = ts_l( x, i - k + 1 );
+
+ for ( uint_t j = i - k + 1; j <= i; ++j )
+ {
+ if ( ts_h( x, j ) > upper )
+ upper = ts_h( x, j );
+ if ( ts_l( x, j ) < lower )
+ lower = ts_l( x, j );
+ }
+
+ y[0][i] = upper - lower;
+ }
+ return 0;
+}
+
+
+