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| author | Ethan Werner <mail@ethanwerner.com> | 2026-07-01 09:42:39 +0400 |
|---|---|---|
| committer | Ethan Werner <mail@ethanwerner.com> | 2026-07-01 09:42:39 +0400 |
| commit | 07e18043145f3d91c8ea7ec3ad41b3c905585277 (patch) | |
| tree | 2bdeae46973f4bdfce263679a4008ac768011f28 /lib/chande_forecast_oscillator.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/chande_forecast_oscillator.c')
| -rw-r--r-- | lib/chande_forecast_oscillator.c | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/lib/chande_forecast_oscillator.c b/lib/chande_forecast_oscillator.c new file mode 100644 index 0000000..6e65bbe --- /dev/null +++ b/lib/chande_forecast_oscillator.c @@ -0,0 +1,67 @@ +// Chande Forecast Oscillator +// +// chande_forecast_oscillator - CFO +// +// (Actual - Forecast) / Forecast * 100, using linear regression forecast +// +// Inputs: 1 +// Outputs: 1 (Oscillator %) +// Constants: 1 (period) + +#include "ts.h" + +typedef struct { + uint_t k; +} ts_chande_forecast_oscillator_params_t; + +ts_parameter_t const ts_chande_forecast_oscillator_p = { .n_inputs = 1, .n_outputs = 1, .n_constants = 1, .params_size = sizeof(ts_chande_forecast_oscillator_params_t) }; + +uint_t ts_chande_forecast_oscillator_offset( ts_constant_t const *c ) +{ + ( void )c; + return ( c ? ((ts_chande_forecast_oscillator_params_t *)c)->k - 1 : 0 ); +} + +int ts_chande_forecast_oscillator( + 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_chande_forecast_oscillator_p ); + if ( !c ) return -1; + uint_t k = ((ts_chande_forecast_oscillator_params_t *)c)->k; + if (k == 0 || n < k) return -1; + + for( uint_t i = k - 1; i < n; ++i ) + { + fp_t sum_x = 0, sum_y = 0, sum_xy = 0, sum_x2 = 0; + for( uint_t j = 0; j < k; ++j ) + { + fp_t xv = (fp_t)j; + fp_t yv = x[0][i - k + 1 + j]; + sum_x += xv; + sum_y += yv; + sum_xy += xv * yv; + sum_x2 += xv * xv; + } + fp_t denom = (fp_t)k * sum_x2 - sum_x * sum_x; + fp_t forecast; + if( denom == 0 ) + forecast = sum_y / (fp_t)k; + else + { + fp_t slope = ( (fp_t)k * sum_xy - sum_x * sum_y ) / denom; + fp_t intercept = ( sum_y - slope * sum_x ) / (fp_t)k; + forecast = intercept + slope * (fp_t)k; + } + if( forecast != 0 ) + y[0][i] = ( x[0][i] - forecast ) / forecast * 100.0; + else + y[0][i] = 0; + } + return 0; +} + + + |