fix: use single-precision functions and handle overflow in truncbf

- Replace pow/trunc with powf/truncf for consistency with float32 operations
- Add overflow handling when scale factor b^n becomes infinite
- Remove unused double-precision dependencies from package.json
- Add test case for scale factor overflow
- Ensure C implementation matches JavaScript precision
Addresses maintainer feedback:
- Uses single-precision packages (powf, truncf)
- NAPI macro already correctly implemented
- manifest.json structure already correct
Closes #649

Author: Amansingh0807

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

@@ -22,8 +22,8 @@
 
 var isnanf = require( '@stdlib/math/base/assert/is-nanf' );
 var isInfinitef = require( '@stdlib/math/base/assert/is-infinitef' );
-var pow = require( '@stdlib/math/base/special/pow' );
-var trunc = require( '@stdlib/math/base/special/trunc' );
+var powf = require( '@stdlib/math/base/special/powf' );
+var truncf = require( '@stdlib/math/base/special/truncf' );
 var float64ToFloat32 = require( '@stdlib/number/float64/base/to-float32' );
 
 
@@ -70,11 +70,16 @@ function truncbf( x, n, b ) {
 		return NaN;
 	}
 
-	// Compute scale factor: s = b^n
-	s = pow( b, n );
+	// Compute scale factor in single precision: s = b^n
+	s = powf( float64ToFloat32( b ), float64ToFloat32( n ) );
+
+	// Handle overflow in scale factor
+	if ( !isFinite( s ) ) {
+		return x;
+	}
 
 	// Multiply by scale, truncate, then divide by scale
-	y = trunc( x * s ) / s;
+	y = truncf( x * s ) / s;
 
 	return float64ToFloat32( y );
 }

lib/node_modules/@stdlib/math/base/special/truncbf/package.json

@@ -38,9 +38,7 @@
     "@stdlib/math/base/assert/is-infinitef": "^0.2.2",
     "@stdlib/math/base/assert/is-nanf": "^0.2.2",
     "@stdlib/math/base/napi/ternary": "^0.2.2",
-    "@stdlib/math/base/special/pow": "^0.2.2",
     "@stdlib/math/base/special/powf": "^0.2.2",
-    "@stdlib/math/base/special/trunc": "^0.2.2",
     "@stdlib/math/base/special/truncf": "^0.2.2",
     "@stdlib/number/float64/base/to-float32": "^0.2.2",
     "@stdlib/utils/library-manifest": "^0.2.2"

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

@@ -44,6 +44,9 @@ float stdlib_base_truncbf( const float x, const int32_t n, const int32_t b ) {
 		return 0.0f / 0.0f;
 	}
 	s = stdlib_base_powf( (float)b, (float)n );
+	if ( isinf( s ) ) {
+		return x;
+	}
 	return stdlib_base_truncf( x * s ) / s;
 }
 

lib/node_modules/@stdlib/math/base/special/truncbf/test/test.js

@@ -25,6 +25,7 @@ var tape = require( 'tape' );
 var isnanf = require( '@stdlib/math/base/assert/is-nanf' );
 var isPositiveZerof = require( '@stdlib/math/base/assert/is-positive-zerof' );
 var isNegativeZerof = require( '@stdlib/math/base/assert/is-negative-zerof' );
+var float64ToFloat32 = require( '@stdlib/number/float64/base/to-float32' );
 var PINF = require( '@stdlib/constants/float32/pinf' );
 var NINF = require( '@stdlib/constants/float32/ninf' );
 var EPS = require( '@stdlib/constants/float32/eps' );
@@ -146,3 +147,16 @@ tape( 'the function returns -infinity if provided -infinity', function test( t )
 	t.strictEqual( v, NINF, 'returns expected value' );
 	t.end();
 });
+
+tape( 'the function handles scale factor overflow gracefully', function test( t ) {
+	var v;
+	
+	// When b^n overflows to Infinity, should return x unchanged
+	v = truncbf( 3.14, 40, 10 );
+	t.strictEqual( v, float64ToFloat32( 3.14 ), 'handles large exponent' );
+	
+	v = truncbf( -2.5, 50, 10 );
+	t.strictEqual( v, float64ToFloat32( -2.5 ), 'handles large exponent with negative x' );
+	
+	t.end();
+});