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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/is_prime.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/is_prime.c')
-rw-r--r--lib/is_prime.c69
1 files changed, 69 insertions, 0 deletions
diff --git a/lib/is_prime.c b/lib/is_prime.c
new file mode 100644
index 0000000..119c9a4
--- /dev/null
+++ b/lib/is_prime.c
@@ -0,0 +1,69 @@
+// Is Prime
+//
+// is_prime
+//
+// Prime number test
+//
+// 1 if prime, 0 otherwise
+//
+// Inputs: 1
+// Outputs: 1
+// Constants: 0
+
+
+#include <math.h>
+#include "ts.h"
+
+
+ts_parameter_t const ts_is_prime_p = { .n_inputs = 1, .n_outputs = 1, .n_constants = 0, .params_size = 0 };
+
+uint_t ts_is_prime_offset( ts_constant_t const *c )
+{
+ ( void )c;
+ return ( 0 );
+}
+
+int ts_is_prime(
+ 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_is_prime_p );
+ (void)c;
+ for( uint_t i = 0; i < n; ++i )
+ {
+ fp_t v = x[0][i];
+ if (v > 1e15 || v < -1e15) { y[0][i] = 0.0; continue; }
+ long n_val = (long)v;
+ if( n_val < 2 )
+ {
+ y[0][i] = 0.0;
+ continue;
+ }
+ if( n_val == 2 )
+ {
+ y[0][i] = 1.0;
+ continue;
+ }
+ if( n_val % 2 == 0 )
+ {
+ y[0][i] = 0.0;
+ continue;
+ }
+ int prime = 1;
+ for( long d = 3; d <= n_val / d; d += 2 )
+ {
+ if( n_val % d == 0 )
+ {
+ prime = 0;
+ break;
+ }
+ }
+ y[0][i] = prime ? 1.0 : 0.0;
+ }
+ return 0;
+}
+
+
+