(function(global,factory){if(typeof define==="function"&&define.amd){define(["module"],factory)}else if(typeof exports!=="undefined"){factory(module)}else{var mod={exports:{}};factory(mod);global.regression=mod.exports}})(this,function(module){"use strict";function _defineProperty(obj,key,value){if(key in obj){Object.defineProperty(obj,key,{value:value,enumerable:true,configurable:true,writable:true})}else{obj[key]=value}return obj}var _extends=Object.assign||function(target){for(var i=1;i<arguments.length;i++){var source=arguments[i];for(var key in source){if(Object.prototype.hasOwnProperty.call(source,key)){target[key]=source[key]}}}return target};function _toConsumableArray(arr){if(Array.isArray(arr)){for(var i=0,arr2=Array(arr.length);i<arr.length;i++){arr2[i]=arr[i]}return arr2}else{return Array.from(arr)}}var DEFAULT_OPTIONS={order:2,precision:2,period:null};function determinationCoefficient(data,results){var predictions=[];var observations=[];data.forEach(function(d,i){if(d[1]!==null){observations.push(d);predictions.push(results[i])}});var sum=observations.reduce(function(a,observation){return a+observation[1]},0);var mean=sum/observations.length;var ssyy=observations.reduce(function(a,observation){var difference=observation[1]-mean;return a+difference*difference},0);var sse=observations.reduce(function(accum,observation,index){var prediction=predictions[index];var residual=observation[1]-prediction[1];return accum+residual*residual},0);return 1-sse/ssyy}function gaussianElimination(input,order){var matrix=input;var n=input.length-1;var coefficients=[order];for(var i=0;i<n;i++){var maxrow=i;for(var j=i+1;j<n;j++){if(Math.abs(matrix[i][j])>Math.abs(matrix[i][maxrow])){maxrow=j}}for(var k=i;k<n+1;k++){var tmp=matrix[k][i];matrix[k][i]=matrix[k][maxrow];matrix[k][maxrow]=tmp}for(var _j=i+1;_j<n;_j++){for(var _k=n;_k>=i;_k--){matrix[_k][_j]-=matrix[_k][i]*matrix[i][_j]/matrix[i][i]}}}for(var _j2=n-1;_j2>=0;_j2--){var total=0;for(var _k2=_j2+1;_k2<n;_k2++){total+=matrix[_k2][_j2]*coefficients[_k2]}coefficients[_j2]=(matrix[n][_j2]-total)/matrix[_j2][_j2]}return coefficients}function round(number,precision){var factor=Math.pow(10,precision);return Math.round(number*factor)/factor}var methods={linear:function linear(data,options){var sum=[0,0,0,0,0];var len=0;for(var n=0;n<data.length;n++){if(data[n][1]!==null){len++;sum[0]+=data[n][0];sum[1]+=data[n][1];sum[2]+=data[n][0]*data[n][0];sum[3]+=data[n][0]*data[n][1];sum[4]+=data[n][1]*data[n][1]}}var run=len*sum[2]-sum[0]*sum[0];var rise=len*sum[3]-sum[0]*sum[1];var gradient=run===0?0:round(rise/run,options.precision);var intercept=round(sum[1]/len-gradient*sum[0]/len,options.precision);var predict=function predict(x){return[round(x,options.precision),round(gradient*x+intercept,options.precision)]};var points=data.map(function(point){return predict(point[0])});return{points:points,predict:predict,equation:[gradient,intercept],r2:round(determinationCoefficient(data,points),options.precision),string:intercept===0?"y = "+gradient+"x":"y = "+gradient+"x + "+intercept}},exponential:function exponential(data,options){var sum=[0,0,0,0,0,0];for(var n=0;n<data.length;n++){if(data[n][1]!==null){sum[0]+=data[n][0];sum[1]+=data[n][1];sum[2]+=data[n][0]*data[n][0]*data[n][1];sum[3]+=data[n][1]*Math.log(data[n][1]);sum[4]+=data[n][0]*data[n][1]*Math.log(data[n][1]);sum[5]+=data[n][0]*data[n][1]}}var denominator=sum[1]*sum[2]-sum[5]*sum[5];var a=Math.exp((sum[2]*sum[3]-sum[5]*sum[4])/denominator);var b=(sum[1]*sum[4]-sum[5]*sum[3])/denominator;var coeffA=round(a,options.precision);var coeffB=round(b,options.precision);var predict=function predict(x){return[round(x,options.precision),round(coeffA*Math.exp(coeffB*x),options.precision)]};var points=data.map(function(point){return predict(point[0])});return{points:points,predict:predict,equation:[coeffA,coeffB],string:"y = "+coeffA+"e^("+coeffB+"x)",r2:round(determinationCoefficient(data,points),options.precision)}},logarithmic:function logarithmic(data,options){var sum=[0,0,0,0];var len=data.length;for(var n=0;n<len;n++){if(data[n][1]!==null){sum[0]+=Math.log(data[n][0]);sum[1]+=data[n][1]*Math.log(data[n][0]);sum[2]+=data[n][1];sum[3]+=Math.pow(Math.log(data[n][0]),2)}}var a=(len*sum[1]-sum[2]*sum[0])/(len*sum[3]-sum[0]*sum[0]);var coeffB=round(a,options.precision);var coeffA=round((sum[2]-coeffB*sum[0])/len,options.precision);var predict=function predict(x){return[round(x,options.precision),round(round(coeffA+coeffB*Math.log(x),options.precision),options.precision)]};var points=data.map(function(point){return predict(point[0])});return{points:points,predict:predict,equation:[coeffA,coeffB],string:"y = "+coeffA+" + "+coeffB+" ln(x)",r2:round(determinationCoefficient(data,points),options.precision)}},power:function power(data,options){var sum=[0,0,0,0,0];var len=data.length;for(var n=0;n<len;n++){if(data[n][1]!==null){sum[0]+=Math.log(data[n][0]);sum[1]+=Math.log(data[n][1])*Math.log(data[n][0]);sum[2]+=Math.log(data[n][1]);sum[3]+=Math.pow(Math.log(data[n][0]),2)}}var b=(len*sum[1]-sum[0]*sum[2])/(len*sum[3]-Math.pow(sum[0],2));var a=(sum[2]-b*sum[0])/len;var coeffA=round(Math.exp(a),options.precision);var coeffB=round(b,options.precision);var predict=function predict(x){return[round(x,options.precision),round(round(coeffA*Math.pow(x,coeffB),options.precision),options.precision)]};var points=data.map(function(point){return predict(point[0])});return{points:points,predict:predict,equation:[coeffA,coeffB],string:"y = "+coeffA+"x^"+coeffB,r2:round(determinationCoefficient(data,points),options.precision)}},polynomial:function polynomial(data,options){var lhs=[];var rhs=[];var a=0;var b=0;var len=data.length;var k=options.order+1;for(var i=0;i<k;i++){for(var l=0;l<len;l++){if(data[l][1]!==null){a+=Math.pow(data[l][0],i)*data[l][1]}}lhs.push(a);a=0;var c=[];for(var j=0;j<k;j++){for(var _l=0;_l<len;_l++){if(data[_l][1]!==null){b+=Math.pow(data[_l][0],i+j)}}c.push(b);b=0}rhs.push(c)}rhs.push(lhs);var coefficients=gaussianElimination(rhs,k).map(function(v){return round(v,options.precision)});var predict=function predict(x){return[round(x,options.precision),round(coefficients.reduce(function(sum,coeff,power){return sum+coeff*Math.pow(x,power)},0),options.precision)]};var points=data.map(function(point){return predict(point[0])});var string="y = ";for(var _i=coefficients.length-1;_i>=0;_i--){if(_i>1){string+=coefficients[_i]+"x^"+_i+" + "}else if(_i===1){string+=coefficients[_i]+"x + "}else{string+=coefficients[_i]}}return{string:string,points:points,predict:predict,equation:[].concat(_toConsumableArray(coefficients)).reverse(),r2:round(determinationCoefficient(data,points),options.precision)}}};function createWrapper(){var reduce=function reduce(accumulator,name){return _extends({_round:round},accumulator,_defineProperty({},name,function(data,supplied){return methods[name](data,_extends({},DEFAULT_OPTIONS,supplied))}))};return Object.keys(methods).reduce(reduce,{})}module.exports=createWrapper()});