LaTeX to CAS translator

This mockup demonstrates the concept of TeX to Computer Algebra System (CAS) conversion.

The demo-application converts LaTeX functions which directly translate to CAS counterparts.

Functions without explicit CAS support are available for translation via a DRMF package (under development).

The following LaTeX input ...

{\displaystyle \hbox{li}(x)=\hbox{Ei}(\ln x) , \,\!}

${\displaystyle {\hbox{li}}(x)={\hbox{Ei}}(\ln x),\,\!}$

... is translated to the CAS output ...

Semantic latex: l \iunit(x) ={\expintEi@{\ln x}}

Confidence: 0.65722105077558

Mathematica

Translation: l*I*(x) == ExpIntegralEi[Log[x]]

Information

Sub Equations

l*I*(x) = ExpIntegralEi[Log[x]]

Free variables

l

x

Symbol info

Imaginary unit was translated to: I

Exponential integral; Example: \expintEi@{x}

Will be translated to: Alternative translations: [ExpIntegralEi[$0]]Constraints: z != 0 Branch Cuts: (-\infty, 0] Relevant links to definitions: DLMF: http://dlmf.nist.gov/6.2#E1 Mathematica:

Natural logarithm; Example: \ln@@{z}

Will be translated to: Log[$0] Constraints: z != 0 Branch Cuts: (-\infty, 0] Relevant links to definitions: DLMF: http://dlmf.nist.gov/4.2#E2 Mathematica: https://reference.wolfram.com/language/ref/Log.html

Tests

Symbolic

Test expression: (l*I*(x))-(ExpIntegralEi[Log[x]])

ERROR:

{
    "result": "ERROR",
    "testTitle": "Simple",
    "testExpression": null,
    "resultExpression": null,
    "wasAborted": false,
    "conditionallySuccessful": false
}

Numeric

SymPy

Translation:

Information

Symbol info

(LaTeX -> SymPy) No translation possible for given token: Cannot extract information from feature set: \expintEi [\expintEi]

Tests

Symbolic

Numeric

Maple

Translation:

Information

Symbol info

(LaTeX -> Maple) No translation possible for given token: Cannot extract information from feature set: \expintEi [\expintEi]

Tests

Symbolic

Numeric

Dependency Graph Information

Includes

$x)$

$x$

${\hbox{li}}(x)={\hbox{Ei}}(\ln x),\,$

Is part of

${\hbox{li}}(x)={\hbox{Ei}}(\ln x),\,$

Complete translation information:

{
  "id" : "FORMULA_22995dbf9018c3eb300778170a8c1241",
  "formula" : "{li}(x)={Ei}(\\ln x)",
  "semanticFormula" : "l \\iunit(x) ={\\expintEi@{\\ln x}}",
  "confidence" : 0.657221050775581,
  "translations" : {
    "Mathematica" : {
      "translation" : "l*I*(x) == ExpIntegralEi[Log[x]]",
      "translationInformation" : {
        "subEquations" : [ "l*I*(x) = ExpIntegralEi[Log[x]]" ],
        "freeVariables" : [ "l", "x" ],
        "tokenTranslations" : {
          "\\iunit" : "Imaginary unit was translated to: I",
          "\\expintEi" : "Exponential integral; Example: \\expintEi@{x}\nWill be translated to: \nAlternative translations: [ExpIntegralEi[$0]]Constraints: z != 0\nBranch Cuts: (-\\infty, 0]\nRelevant links to definitions:\nDLMF:         http://dlmf.nist.gov/6.2#E1\nMathematica:  ",
          "\\ln" : "Natural logarithm; Example: \\ln@@{z}\nWill be translated to: Log[$0]\nConstraints: z != 0\nBranch Cuts: (-\\infty, 0]\nRelevant links to definitions:\nDLMF:         http://dlmf.nist.gov/4.2#E2\nMathematica:  https://reference.wolfram.com/language/ref/Log.html"
        }
      },
      "numericResults" : {
        "overallResult" : "SKIPPED",
        "numberOfTests" : 0,
        "numberOfFailedTests" : 0,
        "numberOfSuccessfulTests" : 0,
        "numberOfSkippedTests" : 0,
        "numberOfErrorTests" : 0,
        "wasAborted" : false,
        "crashed" : false,
        "testCalculationsGroups" : [ ]
      },
      "symbolicResults" : {
        "overallResult" : "ERROR",
        "numberOfTests" : 1,
        "numberOfFailedTests" : 0,
        "numberOfSuccessfulTests" : 0,
        "numberOfSkippedTests" : 0,
        "numberOfErrorTests" : 1,
        "crashed" : false,
        "testCalculationsGroup" : [ {
          "lhs" : "l*I*(x)",
          "rhs" : "ExpIntegralEi[Log[x]]",
          "testExpression" : "(l*I*(x))-(ExpIntegralEi[Log[x]])",
          "testCalculations" : [ {
            "result" : "ERROR",
            "testTitle" : "Simple",
            "testExpression" : null,
            "resultExpression" : null,
            "wasAborted" : false,
            "conditionallySuccessful" : false
          } ]
        } ]
      }
    },
    "SymPy" : {
      "translation" : "",
      "translationInformation" : {
        "tokenTranslations" : {
          "Error" : "(LaTeX -> SymPy) No translation possible for given token: Cannot extract information from feature set: \\expintEi [\\expintEi]"
        }
      }
    },
    "Maple" : {
      "translation" : "",
      "translationInformation" : {
        "tokenTranslations" : {
          "Error" : "(LaTeX -> Maple) No translation possible for given token: Cannot extract information from feature set: \\expintEi [\\expintEi]"
        }
      }
    }
  },
  "positions" : [ ],
  "includes" : [ "x)", "x", "\\hbox{li}(x)=\\hbox{Ei}(\\ln x) , \\," ],
  "isPartOf" : [ "\\hbox{li}(x)=\\hbox{Ei}(\\ln x) , \\," ],
  "definiens" : [ ]
}

Specify your own input

Formula input
Wikitext context	{{Use American English\|date = January 2019}} {{Redirect\|Li(x)\|the polylogarithm denoted by Li<sub>''s''</sub>(''z'')\|Polylogarithm}} {{Short description\|Special function defined by an integral}} In [[mathematics]], the '''logarithmic integral function''' or '''integral logarithm''' li(''x'') is a [[special function]]. It is relevant in problems of [[physics]] and has [[number theory\|number theoretic]] significance. In particular, according to the [[Siegel-Walfisz theorem]] it is a very good [[approximation]] to the [[prime-counting function]], which is defined as the number of [[prime numbers]] less than or equal to a given value <math>x</math>. [[Image:Logarithmic integral function.svg\|thumb\|right\|300px\|Logarithmic integral function plot]] ==Integral representation== The logarithmic integral has an integral representation defined for all positive [[real number]]s {{mvar\|x}} ≠ 1 by the [[integral\|definite integral]] :<math> \operatorname{li}(x) = \int_0^x \frac{dt}{\ln t}. </math> Here, {{math\|ln}} denotes the [[natural logarithm]]. The function {{math\|1/(ln ''t'')}} has a [[mathematical singularity\|singularity]] at {{math\|1=''t'' = 1}}, and the integral for {{math\|''x'' > 1}} is interpreted as a [[Cauchy principal value]], :<math> \operatorname{li}(x) = \lim_{\varepsilon \to 0+} \left( \int_0^{1-\varepsilon} \frac{dt}{\ln t} + \int_{1+\varepsilon}^x \frac{dt}{\ln t} \right).</math> ==Offset logarithmic integral== The '''offset logarithmic integral''' or '''Eulerian logarithmic integral''' is defined as :<math> \operatorname{Li}(x) = \int_2^x \frac{dt}{\ln t} = \operatorname{li}(x) - \operatorname{li}(2). </math> As such, the integral representation has the advantage of avoiding the singularity in the domain of integration. ==Special values== The function li(''x'') has a single positive zero; it occurs at ''x'' ≈ 1.45136 92348 83381 05028 39684 85892 02744 94930... {{OEIS2C\|A070769}}; this number is known as the [[Ramanujan–Soldner constant]]. −Li(0) = li(2) ≈ 1.045163 780117 492784 844588 889194 613136 522615 578151... {{OEIS2C\|A069284}} This is <math>-(\Gamma\left(0,-\ln 2\right) + i\,\pi)</math> where <math>\Gamma\left(a,x\right)</math> is the [[incomplete gamma function]]. It must be understood as the [[Cauchy principal value]] of the function. ==Series representation== The function li(''x'') is related to the ''[[exponential integral]]'' Ei(''x'') via the equation :<math>\hbox{li}(x)=\hbox{Ei}(\ln x) , \,\!</math> which is valid for ''x'' > 0. This identity provides a series representation of li(''x'') as :<math> \operatorname{li}(e^u) = \hbox{Ei}(u) = \gamma + \ln \|u\| + \sum_{n=1}^\infty {u^{n}\over n \cdot n!} \quad \text{ for } u \ne 0 \; , </math> where γ ≈ 0.57721 56649 01532 ... {{OEIS2C\|id=A001620}} is the [[Euler–Mascheroni constant]]. A more rapidly convergent series by [[Srinivasa Ramanujan\|Ramanujan]] <ref>{{MathWorld \| urlname=LogarithmicIntegral \| title=Logarithmic Integral}}</ref> is :<math> \operatorname{li}(x) = \gamma + \ln \ln x + \sqrt{x} \sum_{n=1}^\infty \frac{ (-1)^{n-1} (\ln x)^n} {n! \, 2^{n-1}} \sum_{k=0}^{\lfloor (n-1)/2 \rfloor} \frac{1}{2k+1} . </math> <!-- cribbed from Mathworld, which cites Berndt, B. C. Ramanujan's Notebooks, Part IV. New York: Springer-Verlag, pp. 126–131, 1994. --> ==Asymptotic expansion== The asymptotic behavior for ''x'' → ∞ is :<math> \operatorname{li}(x) = O \left( {x\over \ln x} \right) \; . </math> where <math>O</math> is the [[big O notation]]. The full [[asymptotic expansion]] is :<math> \operatorname{li}(x) \sim \frac{x}{\ln x} \sum_{k=0}^\infty \frac{k!}{(\ln x)^k} </math> or :<math> \frac{\operatorname{li}(x)}{x/\ln x} \sim 1 + \frac{1}{\ln x} + \frac{2}{(\ln x)^2} + \frac{6}{(\ln x)^3} + \cdots. </math> This gives the following more accurate asymptotic behaviour: :<math> \operatorname{li}(x) - {x\over \ln x} = O \left( {x\over \ln^2 x} \right) \; . </math> As an asymptotic expansion, this series is [[divergent series\|not convergent]]: it is a reasonable approximation only if the series is truncated at a finite number of terms, and only large values of ''x'' are employed. This expansion follows directly from the asymptotic expansion for the [[exponential integral]]. This implies e.g. that we can bracket li as: :<math> 1+\frac{1}{\ln x} < \operatorname{li}(x) \frac{\ln x}{x} < 1+\frac{1}{\ln x}+\frac{3}{(\ln x)^2} </math> for all <math>\ln x \ge 11</math>. ==Number theoretic significance== The logarithmic integral is important in [[number theory]], appearing in estimates of the number of [[prime number]]s less than a given value. For example, the [[prime number theorem]] states that: :<math>\pi(x)\sim\operatorname{Li}(x)</math> where <math>\pi(x)</math> denotes the number of primes smaller than or equal to <math>x</math>. Assuming the [[Riemann hypothesis]], we get the even stronger:<ref>Abramowitz and Stegun, p. 230, 5.1.20</ref> :<math>\operatorname{Li}(x)-\pi(x) = O(\sqrt{x}\log x)</math> == See also == * [[Jørgen Pedersen Gram]] * [[Skewes' number]] == References == <references/> {{AS ref\|5\|228}} {{dlmf\|id=6\|title=Exponential, Logarithmic, Sine, and Cosine Integrals\|first=N. M. \|last=Temme}} {{Nonelementary Integral}} [[Category:Special hypergeometric functions]] [[Category:Integrals]]
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LaTeX to CAS translator

Mathematica

Information

Tests

Symbolic

Numeric

SymPy

Information

Tests

Symbolic

Numeric

Maple

Information

Tests

Symbolic

Numeric

Dependency Graph Information

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