/* harmony default export */

/* harmony import */

/*#__PURE__*/

/**
	* If provided a value, the accumulator function returns an updated sum. If not provided a value, the accumulator function returns the current sum.
	*
	* @private
	* @param {number} [x] - new value
	* @returns {(number|null)} sum or null
	*/

/**
* @license Apache-2.0
*
* Copyright (c) 2018 The Stdlib Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
*    http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/

/**
* Compute a sum of squared absolute values incrementally.
*
* @module @stdlib/stats/incr/sumabs2
*
* @example
* var incrsumabs2 = require( '@stdlib/stats/incr/sumabs2' );
*
* var accumulator = incrsumabs2();
*
* var sum = accumulator();
* // returns null
*
* sum = accumulator( 2.0 );
* // returns 4.0
*
* sum = accumulator( -5.0 );
* // returns 29.0
*
* sum = accumulator();
* // returns 29.0
*/

/**
* Returns an accumulator function which incrementally computes a sum of squared absolute values.
*
* @returns {Function} accumulator function
*
* @example
* var accumulator = incrsumabs2();
*
* var sum = accumulator();
* // returns null
*
* sum = accumulator( 2.0 );
* // returns 4.0
*
* sum = accumulator( -5.0 );
* // returns 29.0
*
* sum = accumulator();
* // returns 29.0
*/

/**
* Simple linear regression.
*
* @property {Object} data - object of value arrays
* @property {string} x - explanatory variable
* @property {string} y - response variable
* @property {string} group - grouping variable
* @property {boolean} omitMissing - controls whether to omit missing values in model fitting
* @property {Function} onDiagnostics - callback invoked with diagnostic plots
* @property {Function} onPredict - callback invoked with fitted values and residuals
*/

/***/

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