98 lines
3.9 KiB
JavaScript
98 lines
3.9 KiB
JavaScript
/**
|
|
* LogarithmPlotter - 2D plotter software to make BODE plots, sequences and distribution functions.
|
|
* Copyright (C) 2021-2024 Ad5001
|
|
*
|
|
* This program is free software: you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation, either version 3 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program. If not, see <https://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
import * as Expr from "expression.mjs"
|
|
import * as Utils from "../utils.mjs"
|
|
import Latex from "../math/latex.mjs"
|
|
|
|
/**
|
|
* Represents mathematical object for sequences.
|
|
*/
|
|
export class Sequence extends Expr.Expression {
|
|
constructor(name, baseValues = {}, valuePlus = 1, expr = "") {
|
|
// u[n+valuePlus] = expr
|
|
super(expr)
|
|
this.name = name
|
|
this.baseValues = baseValues
|
|
this.calcValues = Object.assign({}, baseValues)
|
|
this.latexValues = Object.assign({}, baseValues)
|
|
for(let n in this.calcValues)
|
|
if(['string', 'number'].includes(typeof this.calcValues[n])) {
|
|
let parsed = Modules.ExprParser.parse(this.calcValues[n].toString()).simplify()
|
|
this.latexValues[n] = Latex.expression(parsed.tokens)
|
|
this.calcValues[n] = parsed.evaluate()
|
|
}
|
|
this.valuePlus = parseInt(valuePlus)
|
|
}
|
|
|
|
isConstant() {
|
|
return this.expr.indexOf("n") === -1
|
|
}
|
|
|
|
execute(n = 1) {
|
|
if(n in this.calcValues)
|
|
return this.calcValues[n]
|
|
this.cache(n)
|
|
return this.calcValues[n]
|
|
}
|
|
|
|
simplify(n = 1) {
|
|
if(n in this.calcValues)
|
|
return Utils.makeExpressionReadable(this.calcValues[n].toString())
|
|
this.cache(n)
|
|
return Utils.makeExpressionReadable(this.calcValues[n].toString())
|
|
}
|
|
|
|
cache(n = 1) {
|
|
let str = Utils.simplifyExpression(this.calc.substitute('n', n-this.valuePlus).toString())
|
|
let expr = Modules.ExprParser.parse(str).simplify()
|
|
// Cache values required for this one.
|
|
if(!this.calcValues[n-this.valuePlus] && n-this.valuePlus > 0)
|
|
this.cache(n-this.valuePlus)
|
|
// Setting current variables
|
|
Modules.ExprParser.currentVars = Object.assign(
|
|
{'n': n-this.valuePlus}, // Just in case, add n (for custom functions)
|
|
Modules.Objects.currentObjectsByName,
|
|
{[this.name]: this.calcValues}
|
|
)
|
|
this.calcValues[n] = expr.evaluate(Modules.ExprParser.currentVars)
|
|
}
|
|
|
|
toString(forceSign=false) {
|
|
let str = Utils.makeExpressionReadable(this.calc.toString())
|
|
if(str[0] !== '-' && forceSign) str = '+' + str
|
|
let subtxt = this.valuePlus === 0 ? 'ₙ' : Utils.textsub('n+' + this.valuePlus)
|
|
let ret = `${this.name}${subtxt} = ${str}${this.baseValues.length === 0 ? '' : "\n"}`
|
|
ret += Object.keys(this.baseValues).map(
|
|
n => `${this.name}${Utils.textsub(n)} = ${this.baseValues[n]}`
|
|
).join('; ')
|
|
return ret
|
|
}
|
|
|
|
toLatexString(forceSign=false) {
|
|
let str = this.latexMarkup
|
|
if(str[0] !== '-' && forceSign) str = '+' + str
|
|
let subtxt = '_{n' + (this.valuePlus === 0 ? '' : '+' + this.valuePlus) + '}'
|
|
let ret = `\\begin{array}{l}${Latex.variable(this.name)}${subtxt} = ${str}${this.latexValues.length === 0 ? '' : "\n"}\\\\`
|
|
ret += Object.keys(this.latexValues).map(
|
|
n => `${this.name}_{${n}} = ${this.latexValues[n]}`
|
|
).join('; ') + "\\end{array}"
|
|
return ret
|
|
}
|
|
}
|