refactor: modify C implementation to accept double instead of int32

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---

Author: gunjjoshi

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

@@ -176,19 +176,19 @@ for ( i = 0; i < 64; i++ ) {
 Computes the nth [Tribonacci number][tribonacci-number].
 
 ```c
-double out = stdlib_base_tribonacci( 0 );
-// returns 0
+double out = stdlib_base_tribonacci( 0.0 );
+// returns 0.0
 
-out = stdlib_base_tribonacci( 1 );
-// returns 0
+out = stdlib_base_tribonacci( 1.0 );
+// returns 0.0
 ```
 
 The function accepts the following arguments:
 
--   **n**: `[in] int32_t` input value.
+-   **n**: `[in] double` input value.
 
 ```c
-double stdlib_base_tribonacci( const int32_t n );
+double stdlib_base_tribonacci( const double n );
 ```
 
 </section>
@@ -212,15 +212,14 @@ double stdlib_base_tribonacci( const int32_t n );
 ```c
 #include "stdlib/math/base/special/tribonacci.h"
 #include <stdio.h>
-#include <stdint.h>
 
 int main( void ) {
-    int32_t i;
+    double i;
     double v;
 
-    for ( i = 0; i < 64; i++ ) {
+    for ( i = 0.0; i < 64.0; i++ ) {
         v = stdlib_base_tribonacci( i );
-        printf( "tribonacci(%d) = %lf\n", i, v );
+        printf( "tribonacci(%lf) = %lf\n", i, v );
     }
 }
 ```

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

@@ -90,14 +90,14 @@ static double rand_double( void ) {
 * @return elapsed time in seconds
 */
 static double benchmark( void ) {
-	int32_t x[ 100 ];
+	double x[ 100 ];
 	double elapsed;
 	double t;
 	double y;
 	int i;
 
 	for ( i = 0; i < 100; i++ ) {
-		x[ i ] = (int32_t)floor( 40.0*rand_double() );
+		x[ i ] = floor( 40.0*rand_double() );
 	}
 
 	t = tic();

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

@@ -18,14 +18,13 @@
 
 #include "stdlib/math/base/special/tribonacci.h"
 #include <stdio.h>
-#include <stdint.h>
 
 int main( void ) {
-	int32_t i;
+	double i;
 	double v;
 
-	for ( i = 0; i < 64; i++ ) {
+	for ( i = 0.0; i < 64.0; i++ ) {
 		v = stdlib_base_tribonacci( i );
-		printf( "tribonacci(%d) = %lf\n", i, v );
+		printf( "tribonacci(%lf) = %lf\n", i, v );
 	}
 }

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

@@ -19,16 +19,14 @@
 #ifndef STDLIB_MATH_BASE_SPECIAL_TRIBONACCI_H
 #define STDLIB_MATH_BASE_SPECIAL_TRIBONACCI_H
 
-#include <stdint.h>
-
 #ifdef __cplusplus
 extern "C" {
 #endif
 
 /**
 * Computes the nth Tribonacci number.
 */
-double stdlib_base_tribonacci( const int32_t n );
+double stdlib_base_tribonacci( const double n );
 
 #ifdef __cplusplus
 };

lib/node_modules/@stdlib/math/base/special/tribonacci/lib/main.js

@@ -21,7 +21,7 @@
 // MODULES //
 
 var isnan = require( '@stdlib/math/base/assert/is-nan' );
-var isInteger = require( '@stdlib/math/base/assert/is-integer' );
+var isNonnegativeInteger = require( '@stdlib/math/base/assert/is-nonnegative-integer' );
 var FLOAT64_MAX_SAFE_NTH_TRIBONACCI = require( '@stdlib/constants/float64/max-safe-nth-tribonacci' ); // eslint-disable-line id-length
 var TRIBONACCI = require( './tribonacci.json' );
 
@@ -77,8 +77,7 @@ var TRIBONACCI = require( './tribonacci.json' );
 function tribonacci( n ) {
 	if (
 		isnan( n ) ||
-		isInteger( n ) === false ||
-		n < 0 ||
+		!isNonnegativeInteger( n ) ||
 		n > FLOAT64_MAX_SAFE_NTH_TRIBONACCI
 	) {
 		return NaN;

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

@@ -37,7 +37,9 @@
       "libpath": [],
       "dependencies": [
         "@stdlib/math/base/napi/unary",
-        "@stdlib/constants/float64/max-safe-nth-tribonacci"
+        "@stdlib/constants/float64/max-safe-nth-tribonacci",
+        "@stdlib/math/base/assert/is-nan",
+        "@stdlib/math/base/assert/is-nonnegative-integer"
       ]
     },
     {
@@ -51,7 +53,9 @@
       "libraries": [],
       "libpath": [],
       "dependencies": [
-        "@stdlib/constants/float64/max-safe-nth-tribonacci"
+        "@stdlib/constants/float64/max-safe-nth-tribonacci",
+        "@stdlib/math/base/assert/is-nan",
+        "@stdlib/math/base/assert/is-nonnegative-integer"
       ]
     },
     {
@@ -65,7 +69,9 @@
       "libraries": [],
       "libpath": [],
       "dependencies": [
-        "@stdlib/constants/float64/max-safe-nth-tribonacci"
+        "@stdlib/constants/float64/max-safe-nth-tribonacci",
+        "@stdlib/math/base/assert/is-nan",
+        "@stdlib/math/base/assert/is-nonnegative-integer"
       ]
     }
   ]

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

@@ -19,4 +19,4 @@
 #include "stdlib/math/base/special/tribonacci.h"
 #include "stdlib/math/base/napi/unary.h"
 
-STDLIB_MATH_BASE_NAPI_MODULE_I_D( stdlib_base_tribonacci )
+STDLIB_MATH_BASE_NAPI_MODULE_D_D( stdlib_base_tribonacci )

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

@@ -18,6 +18,9 @@
 
 #include "stdlib/math/base/special/tribonacci.h"
 #include "stdlib/constants/float64/max_safe_nth_tribonacci.h"
+#include "stdlib/math/base/assert/is_nonnegative_integer.h"
+#include "stdlib/math/base/assert/is_nan.h"
+#include <stdlib.h>
 
 static const int64_t tribonacci_value[ 64 ] = {
 	0,
@@ -93,12 +96,12 @@ static const int64_t tribonacci_value[ 64 ] = {
 * @return      output value
 *
 * @example
-* double out = stdlib_base_tribonacci( 1 );
-* // returns 0
+* double out = stdlib_base_tribonacci( 1.0 );
+* // returns 0.0
 */
-double stdlib_base_tribonacci( const int32_t n ) {
-	if ( n < 0 || n > STDLIB_CONSTANT_FLOAT64_MAX_SAFE_NTH_TRIBONACCI ) {
+double stdlib_base_tribonacci( const double n ) {
+	if ( stdlib_base_is_nan( n ) || !stdlib_base_is_nonnegative_integer( n ) || n > STDLIB_CONSTANT_FLOAT64_MAX_SAFE_NTH_TRIBONACCI ) {
 		return 0.0 / 0.0; // NaN
 	}
-	return tribonacci_value[ n ];
+	return tribonacci_value[ (size_t)n ];
 }

lib/node_modules/@stdlib/math/base/special/tribonacci/test/test.native.js

@@ -23,6 +23,7 @@
 var resolve = require( 'path' ).resolve;
 var tape = require( 'tape' );
 var isnan = require( '@stdlib/math/base/assert/is-nan' );
+var PINF = require( '@stdlib/constants/float64/pinf' );
 var tryRequire = require( '@stdlib/utils/try-require' );
 
 
@@ -58,6 +59,24 @@ tape( 'if provided a negative number, the function returns `NaN`', opts, functio
 	t.end();
 });
 
+tape( 'if provided positive infinity, the function returns `NaN`', function test( t ) {
+	var v = tribonacci( PINF );
+	t.strictEqual( isnan( v ), true, 'returns expected value' );
+	t.end();
+});
+
+tape( 'if provided `NaN`, the function returns `NaN`', function test( t ) {
+	var v = tribonacci( NaN );
+	t.strictEqual( isnan( v ), true, 'returns expected value' );
+	t.end();
+});
+
+tape( 'if provided a non-integer, the function returns `NaN`', function test( t ) {
+	var v = tribonacci( 3.14 );
+	t.strictEqual( isnan( v ), true, 'returns expected value' );
+	t.end();
+});
+
 tape( 'the function returns the nth Tribonacci number', opts, function test( t ) {
 	var v;
 	var i;