import get from 'lodash-es/get.js'
import each from 'lodash-es/each.js'
import map from 'lodash-es/map.js'
import size from 'lodash-es/size.js'
import isnum from 'wsemi/src/isnum.mjs'
import isbol from 'wsemi/src/isbol.mjs'
import iseobj from 'wsemi/src/iseobj.mjs'
import isearr from 'wsemi/src/isearr.mjs'
import ispint from 'wsemi/src/ispint.mjs'
import cint from 'wsemi/src/cint.mjs'
import cdbl from 'wsemi/src/cdbl.mjs'
import { PolynomialRegression } from 'ml-regression-polynomial'
/**
* 針對x,y數據進行多項式回歸(y=b+m1*x+m2*x^2+...)
*
* Unit Test: {@link https://github.com/yuda-lyu/w-statistic/blob/master/test/regPoly.test.js Github}
* @memberOf w-statistic
* @param {Array} arr 輸入陣列，只提取有效數字(或為字串的數字)進行計算
* @param {Object} [opt={}] 輸入設定物件，預設{}
* @param {Number} [opt.interpX=null] 輸入經由回歸結果內插指定x值數字，預設null
* @param {Boolean} [opt.useRegIntercept=true] 輸入是否回歸使用截距布林值，預設true
* @param {Boolean} [opt.useSync=false] 輸入是否使用同步函數布林值，預設false
* @returns {Object|Promise} 若useSync=true回傳回歸結果物件，若useSync=false則回傳Promise，此時若成功則resolve回歸結果物件，若失敗則reject錯誤訊息
* @example
*
* async function test() {
*
* let arr
* let r
*
* arr = [
* [50, 3.3], [50, 2.8],
* [50, 2.9], [70, 2.3],
* [70, 2.6], [70, 2.1],
* [80, 2.5], [80, 2.9],
* [80, 2.4], [90, 3],
* [90, 3.1], [90, 2.8],
* [100, 3.3], [100, 3.5],
* [100, 3]
* ]
* r = await regPoly(arr, 2)
* console.log(r)
* // => {
* // b: 7.960481099654818,
* // m1: -0.15371134020614285,
* // m2: 0.0010756013745701653
* // }
*
* arr = [
* [50, 3.3], [50, 2.8],
* [50, 2.9], [70, 2.3],
* [70, 2.6], [70, 2.1],
* [80, 2.5], [80, 2.9],
* [80, 2.4], [90, 3],
* [90, 3.1], [90, 2.8],
* [100, 3.3], [100, 3.5],
* [100, 3]
* ]
* r = await regPoly(arr, 3)
* console.log(r)
* // => {
* // b: 21.051572327842386,
* // m1: -0.7142872117740979,
* // m2: 0.0087657232709057,
* // m3: -0.000034014675054462467
* // }
*
* arr = [
* [50, 3.3], [50, 2.8],
* [50, 2.9], [70, 2.3],
* [70, 2.6], [70, 2.1],
* [80, 2.5], [80, 2.9],
* [80, 2.4], [90, 3],
* [90, 3.1], [90, 2.8],
* [100, 3.3], [100, 3.5],
* [100, 3]
* ]
* r = await regPoly(arr, 2, { useRegIntercept: false }) //不使用截距, 也就是截距b=0
* console.log(r)
* // => { b: 0, m1: 0.06524644304242452, m2: -0.00035672260356343373 }
*
* arr = [
* [50, 3.3], [50, 2.8],
* [50, 2.9], [70, 2.3],
* [70, 2.6], [70, 2.1],
* [80, 2.5], [80, 2.9],
* [80, 2.4], [90, 3],
* [90, 3.1], [90, 2.8],
* [100, 3.3], [100, 3.5],
* [100, 3]
* ]
* r = await regPoly(arr, 2, { interpX: 80 })
* console.log(r)
* // => {
* // b: 7.960481099654818,
* // m1: -0.15371134020614285,
* // m2: 0.0010756013745701653,
* // interpX: 80,
* // interpY: 2.5474226804124473
* // }
*
* arr = [
* [50, 3.3], [50, 2.8],
* [50, 2.9], [70, 2.3],
* [70, 2.6], [70, 2.1],
* [80, 2.5], [80, 2.9],
* [80, 2.4], [90, 3],
* [90, 3.1], [90, 2.8],
* [100, 3.3], [100, 3.5],
* [100, 3]
* ]
* r = regPoly(arr, 2, { useSync: true }) //使用同步函數(sync)
* console.log(r)
* // => {
* // b: 7.960481099654818,
* // m1: -0.15371134020614285,
* // m2: 0.0010756013745701653
* // }
*
* arr = [
* [1, 2.5],
* [2.5, 1.1],
* [4, 0.5],
* ]
* r = await regPoly(arr, 1)
* console.log(r)
* // => { b: 3.0333333333333314, m1: -0.666666666666666 }
*
* }
* test()
* .catch((err) => {
* console.log(err)
* })
*
*/
function regPoly(arr, degree, opt = {}) {
//interpX
let interpX = get(opt, 'interpX')
if (!isnum(interpX)) {
interpX = null
}
//useRegIntercept, 是否回歸使用截距
let useRegIntercept = get(opt, 'useRegIntercept')
if (!isbol(useRegIntercept)) {
useRegIntercept = true
}
//useSync
let useSync = get(opt, 'useSync')
if (!isbol(useSync)) {
useSync = false
}
//_sync
let _sync = () => {
//check arr
if (!isearr(arr)) {
throw new Error(`arr is not an effective array`)
}
//check degree
if (!ispint(degree)) {
throw new Error(`degree[${degree}] is not an integer`)
}
degree = cint(degree)
if (degree < 1) {
throw new Error(`degree[${degree}] < 1`)
}
//rs
let rs = []
each(arr, (v) => {
let x = get(v, 0)
let y = get(v, 1)
if (isnum(x) && isnum(y)) {
rs.push([cdbl(x), cdbl(y)])
}
})
// console.log('rs', rs)
//check
if (size(rs) === 0) {
throw new Error(`no effective data`)
}
//PolynomialRegression
let x = map(rs, 0)
let y = map(rs, 1)
let optPR = {
interceptAtZero: !useRegIntercept,
}
let regression = new PolynomialRegression(x, y, degree, optPR)
// console.log('regression', regression)
// console.log('regression.coefficients', regression.coefficients)
// from 0 to degree, regression.coefficients[0] -> b, regression.coefficients[1] -> m1, regression.coefficients[2] -> m2, ...
// console.log(regression.predict(80)) // Apply the model to some x value
// console.log(regression.toString(10)) // Prints a human-readable version of the function.
// console.log(regression.toLaTeX())
// console.log(regression.score(x, y))
//r
let r = {}
if (useRegIntercept) {
each(regression.coefficients, (v, k) => {
if (k === 0) {
r['b'] = v
}
else {
r[`m${k}`] = v
}
})
}
else {
r['b'] = 0
each(regression.coefficients, (v, k) => {
r[`m${k + 1}`] = v
})
}
// console.log('r', r)
//interpX
if (isnum(interpX)) {
interpX = cdbl(interpX)
let interpY = regression.predict(interpX)
r.interpX = interpX
r.interpY = interpY
}
return r
}
//_async
let _async = async () => {
let r = null
try {
r = _sync()
if (iseobj(r)) {
return r
}
else {
return Promise.reject(`no effective data`)
}
}
catch (err) {
console.log(err)
return Promise.reject(err.message)
}
}
if (useSync) {
return _sync()
}
else {
return _async()
}
}
export default regPoly