refactor: update implementation to handle nonnegative weights

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Author: anandkaranubc

lib/node_modules/@stdlib/stats/incr/wstdev/README.md

@@ -33,7 +33,7 @@ s = \sqrt{\frac{\displaystyle\sum_{i=0}^{n-1} w_{i} \left( x_{i} - \bar{x} \righ
 ```
 
 <!-- <div class="equation" align="center" data-raw-text="s = \sqrt{\frac{\displaystyle\sum_{i=0}^{n-1} w_{i} \left( x_{i} - \bar{x} \right)^2}{\displaystyle\sum_{i=0}^{n-1} w_{i}}}" data-equation="eq:weighted_arithmetic_mean">
-    <img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@adbea9806383f70c982e3191475c874efba1296b/lib/node_modules/@stdlib/stats/incr/wmean/docs/img/equation_weighted_standard_deviation.svg" alt="Equation for the weighted arithmetic mean.">
+    <img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@adbea9806383f70c982e3191475c874efba1296b/lib/node_modules/@stdlib/stats/incr/wstdev/docs/img/equation_weighted_standard_deviation.svg" alt="Equation for the weighted arithmetic mean.">
     <br>
 </div> -->
 
@@ -133,7 +133,7 @@ console.log( accumulator() );
 ## See Also
 
 -   <span class="package-name">[`@stdlib/stats/incr/kurtosis`][@stdlib/stats/incr/kurtosis]</span><span class="delimiter">: </span><span class="description">compute a corrected sample excess kurtosis incrementally.</span>
--   <span class="package-name">[`@stdlib/stats/incr/mean`][@stdlib/stats/incr/mean]</span><span class="delimiter">: </span><span class="description">compute an arithmetic mean incrementally.</span>
+-   <span class="package-name">[`@stdlib/stats/incr/wmean`][@stdlib/stats/incr/wmean]</span><span class="delimiter">: </span><span class="description">compute a weighted arithmetic mean incrementally.</span>
 -   <span class="package-name">[`@stdlib/stats/incr/stdev`][@stdlib/stats/incr/stdev]</span><span class="delimiter">: </span><span class="description">compute a corrected sample standard deviation incrementally.</span>
 -   <span class="package-name">[`@stdlib/stats/incr/mstdev`][@stdlib/stats/incr/mstdev]</span><span class="delimiter">: </span><span class="description">compute a moving corrected sample standard deviation incrementally.</span>
 -   <span class="package-name">[`@stdlib/stats/incr/skewness`][@stdlib/stats/incr/skewness]</span><span class="delimiter">: </span><span class="description">compute a corrected sample skewness incrementally.</span>
@@ -148,16 +148,15 @@ console.log( accumulator() );
 
 <section class="links">
 
-<!-- NOTE: The link below needs to be updated to a more accurate or relevant source. -->
 [weighted-standard-deviation]: https://en.wikipedia.org/wiki/Weighted_arithmetic_mean#Weighted_sample_variance
 
 <!-- <related-links> -->
 
-[@stdlib/stats/incr/stdev]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/stats/incr/stdev
-
 [@stdlib/stats/incr/kurtosis]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/stats/incr/kurtosis
 
-[@stdlib/stats/incr/mean]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/stats/incr/mean
+[@stdlib/stats/incr/wmean]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/stats/incr/wmean
+
+[@stdlib/stats/incr/stdev]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/stats/incr/stdev
 
 [@stdlib/stats/incr/mstdev]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/stats/incr/mstdev