refactor!: modify C implementation to accept float value instead of int32 in math/base/special/negalucasf

This commit updates the signature of the C API to accept a float rather than int32. The rationale was so that users get the same results/behavior in both JavaScript and C. This arose in the context of ufuncs, where the diverging type signatures meant differences in what dtypes would be permissible. Instead, we decided to unify and ensure the behavior is consistent.

BREAKING CHANGE: update signature to accept floats

User code should behave similarly in the primary case of providing integer-valued input values. However, no longer will real-values truncate. Now, real-valued inputs will result in `NaN`, which is, arguably, better behavior, as real-to-integer truncation can be a source of silent bugs.

PR-URL: #7956
Co-authored-by: Athan Reines <[email protected]>
Reviewed-by: Athan Reines <[email protected]>

Author: gunjjoshi

lib/node_modules/@stdlib/math/base/special/negalucasf/README.md

@@ -191,19 +191,19 @@ for ( i = 0; i > -35; i-- ) {
 Computes the nth [negaLucas number][lucas-number] in single-precision floating-point format.
 
 ```c
-float out = stdlib_base_negalucasf( 0 );
+float out = stdlib_base_negalucasf( 0.0f );
 // returns 0.0f
 
-out = stdlib_base_negalucasf( -1 );
+out = stdlib_base_negalucasf( -1.0f );
 // returns -1.0f
 ```
 
 The function accepts the following arguments:
 
--   **n**: `[in] int32_t` input value.
+-   **n**: `[in] float` input value.
 
 ```c
-float stdlib_base_negalucasf( const int32_t n );
+float stdlib_base_negalucasf( const float n );
 ```
 
 </section>
@@ -227,15 +227,14 @@ float stdlib_base_negalucasf( const int32_t n );
 ```c
 #include "stdlib/math/base/special/negalucasf.h"
 #include <stdio.h>
-#include <stdint.h>
 
 int main( void ) {
-    int32_t i;
+    float i;
     float v;
 
-    for ( i = 0; i > -35; i-- ) {
+    for ( i = 0.0f; i > -35.0f; i-- ) {
         v = stdlib_base_negalucasf( i );
-        printf( "negalucasf(%d) = %f\n", i, v );
+        printf( "negalucasf(%f) = %f\n", i, v );
     }
 }
 ```

lib/node_modules/@stdlib/math/base/special/negalucasf/benchmark/c/native/benchmark.c

@@ -30,7 +30,7 @@
 /**
 * Prints the TAP version.
 */
-void print_version() {
+static void print_version( void ) {
 	printf( "TAP version 13\n" );
 }
 
@@ -91,13 +91,13 @@ static float rand_float( void ) {
 */
 static double benchmark( void ) {
 	double elapsed;
-	int32_t x[ 100 ];
+	float x[ 100 ];
 	double t;
 	float y;
 	int i;
 
 	for ( i = 0; i < 100; i++ ) {
-		x[ i ] = (int32_t)( 34.0f * rand_float() );
+		x[ i ] = ( 34.0f * rand_float() );
 	}
 
 	t = tic();

lib/node_modules/@stdlib/math/base/special/negalucasf/examples/c/example.c

@@ -18,14 +18,13 @@
 
 #include "stdlib/math/base/special/negalucasf.h"
 #include <stdio.h>
-#include <stdint.h>
 
 int main( void ) {
-	int32_t i;
+	float i;
 	float v;
 
-	for ( i = 0; i > -35; i-- ) {
+	for ( i = 0.0f; i > -35.0f; i-- ) {
 		v = stdlib_base_negalucasf( i );
-		printf( "negalucasf(%d) = %f\n", i, v );
+		printf( "negalucasf(%f) = %f\n", i, v );
 	}
 }

lib/node_modules/@stdlib/math/base/special/negalucasf/include/stdlib/math/base/special/negalucasf.h

@@ -19,8 +19,6 @@
 #ifndef STDLIB_MATH_BASE_SPECIAL_NEGALUCASF_H
 #define STDLIB_MATH_BASE_SPECIAL_NEGALUCASF_H
 
-#include <stdint.h>
-
 /*
 * If C++, prevent name mangling so that the compiler emits a binary file having undecorated names, thus mirroring the behavior of a C compiler.
 */
@@ -31,7 +29,7 @@ extern "C" {
 /**
 * Computes the nth negaLucas number in single-precision floating-point format.
 */
-float stdlib_base_negalucasf( const int32_t n );
+float stdlib_base_negalucasf( const float n );
 
 #ifdef __cplusplus
 }

lib/node_modules/@stdlib/math/base/special/negalucasf/manifest.json

@@ -37,8 +37,9 @@
       "libpath": [],
       "dependencies": [
         "@stdlib/math/base/napi/unary",
-        "@stdlib/math/base/special/labs",
-        "@stdlib/constants/float32/max-safe-nth-lucas"
+        "@stdlib/math/base/special/absf",
+        "@stdlib/constants/float32/max-safe-nth-lucas",
+        "@stdlib/math/base/assert/is-integerf"
       ]
     },
     {
@@ -52,8 +53,9 @@
       "libraries": [],
       "libpath": [],
       "dependencies": [
-        "@stdlib/math/base/special/labs",
-        "@stdlib/constants/float32/max-safe-nth-lucas"
+        "@stdlib/math/base/special/absf",
+        "@stdlib/constants/float32/max-safe-nth-lucas",
+        "@stdlib/math/base/assert/is-integerf"
       ]
     },
     {
@@ -67,8 +69,9 @@
       "libraries": [],
       "libpath": [],
       "dependencies": [
-        "@stdlib/math/base/special/labs",
-        "@stdlib/constants/float32/max-safe-nth-lucas"
+        "@stdlib/math/base/special/absf",
+        "@stdlib/constants/float32/max-safe-nth-lucas",
+        "@stdlib/math/base/assert/is-integerf"
       ]
     }
   ]

lib/node_modules/@stdlib/math/base/special/negalucasf/src/addon.c

@@ -19,4 +19,4 @@
 #include "stdlib/math/base/special/negalucasf.h"
 #include "stdlib/math/base/napi/unary.h"
 
-STDLIB_MATH_BASE_NAPI_MODULE_I_F( stdlib_base_negalucasf )
+STDLIB_MATH_BASE_NAPI_MODULE_F_F( stdlib_base_negalucasf )

lib/node_modules/@stdlib/math/base/special/negalucasf/src/main.c

@@ -17,8 +17,11 @@
 */
 
 #include "stdlib/math/base/special/negalucasf.h"
-#include "stdlib/math/base/special/labs.h"
+#include "stdlib/math/base/assert/is_integerf.h"
+#include "stdlib/math/base/special/absf.h"
 #include "stdlib/constants/float32/max_safe_nth_lucas.h"
+#include <stdint.h>
+#include <stdlib.h>
 
 static const int32_t negalucasf_value[ 35 ] = {
 	2,
@@ -65,17 +68,17 @@ static const int32_t negalucasf_value[ 35 ] = {
 * @return      output value
 *
 * @example
-* float out = stdlib_base_negalucasf( -1 );
-* // returns -1
+* float out = stdlib_base_negalucasf( -1.0f );
+* // returns -1.0f
 *
 * @example
-* float out = stdlib_base_negalucasf( 1 );
+* float out = stdlib_base_negalucasf( 1.0f );
 * // returns NaN
 */
-float stdlib_base_negalucasf( const int32_t n ) {
-	int32_t an = stdlib_base_labs( n );
-	if ( n > 0 || an > STDLIB_CONSTANT_FLOAT32_MAX_SAFE_NTH_LUCAS ) {
+float stdlib_base_negalucasf( const float n ) {
+	float an = stdlib_base_absf( n );
+	if ( !stdlib_base_is_integerf( n ) || n > 0.0f || an > STDLIB_CONSTANT_FLOAT32_MAX_SAFE_NTH_LUCAS ) {
 		return 0.0f / 0.0f; // NaN
 	}
-	return negalucasf_value[ an ];
+	return negalucasf_value[ (size_t)an ];
 }