fix: update return type

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---

Author: kgryte

lib/node_modules/@stdlib/blas/ext/base/ndarray/csum/docs/types/index.d.ts

@@ -21,6 +21,7 @@
 /// <reference types="@stdlib/types"/>
 
 import { complex64ndarray } from '@stdlib/types/ndarray';
+import { Complex64 } from '@stdlib/types/complex';
 
 /**
 * Computes the sum of all elements in a one-dimensional single-precision complex floating-point ndarray.
@@ -38,7 +39,7 @@ import { complex64ndarray } from '@stdlib/types/ndarray';
 * var v = csum( [ x ] );
 * // returns <Complex64>[ 5.0, 5.0 ]
 */
-declare function csum( arrays: [ complex64ndarray ] ): number;
+declare function csum( arrays: [ complex64ndarray ] ): Complex64;
 
 
 // EXPORTS //

lib/node_modules/@stdlib/blas/ext/base/ndarray/csum/docs/types/test.ts

@@ -24,13 +24,13 @@ import csum = require( './index' );
 
 // TESTS //
 
-// The function returns a number...
+// The function returns a complex number...
 {
 	const x = zeros( [ 10 ], {
 		'dtype': 'complex64'
 	});
 
-	csum( [ x ] ); // $ExpectType number
+	csum( [ x ] ); // $ExpectType Complex64
 }
 
 // The compiler throws an error if the function is provided a first argument which is not an array of ndarrays...