I am using a single unified LaTeX doc to create problem sets and solutions:
\item What is one plus one?
\begin{soln}
The answer is "two".
\end{soln}
In LaTeX, I define this environment with (simplified):
\NewEnviron{soln}
{
\ifsolutions\expandafter
\BODY
\fi
}
That is, if \solutionsfalse has been defined in LaTeX, it prints:
1. What is one plus one?
and if \solutionstrue has been defined, it prints:
1. What is one plus one?
** The answer is two **
I'm trying to replicate this in pandoc to generate HTML or MD files from the latex input, but I've run against the wall. Pandoc doesn't honor any kind of /if /else /fi statement in LaTeX, I think. Pandoc doesn't honor the comment environment, which would also work with \excludecomment{soln}. So, I can't come up with a shim.tex file that would replicate the 'ignore stuff in the soln environment'.
The next way to go would, I guess, be to do something in luatex that pandoc can talk to, or to define the custom environment to pandoc with a filter? But the documentation for those systems is extremely heavyweight - there's no easy way in.
Can anyone suggest a solution to this?
Ideally, I want to run two different shell commands. Command A should omit all content in the soln environment. Command B, ideally, should turn all regular text blue, and show all content in the soln environment in black color.
(P.S. The xcolor package also seems unsupported in native pandoc, although there is a filter that doesn't work for me.)
Edit
Following comments by #tarleb and #mb21, I guess I have to try to work out how filters work. Again, the documentation here is terrible - it wants you to know everything before you can do anything.
I tried this:
return {
{
RawBlock = function(elem)
print(elem.text)
if starts_with('\\begin{soln}', elem.text) then
return pandoc.RawBlock(elem.format,"SOLN")
else
return elem
end
end,
}
}
and ran it with
pandoc --lua-filter ifdef.lua --mathjax -s hw01.tex -s -o hw01.html
But there is nothing on stdout from the print statement, and my document is unchanged, so the RawBlocks are apparently not processed by the lua filter unless the -f latex+raw_tex flag is passed. But passing those flags means that pandoc doesn't actually process the \include commands in the latex, so my filter wont' see the subdocuments.
Apparently, the answer is "No, pandoc cannot support new latex environment", because it would require modifying the parser. Although the -f latex+raw_tex can disable big parts of the parser, that just means the document is largely unparsed, which isn't what I want.
Please tell me if I'm wrong.
I am a relatively new IPython Notebook user and I am using IPython 3.2.1. So upfront, my apologies if I did not read some documentation carefully!
I am trying to typeset some LaTeX in my Notebook intended for a presentation. I tried to utilize MathJax capabilities better than what's (supposedly) available by default and so tried incorporating other extensions that come with MathJax explicitly. In particular, I tried getting my IPython Notebook to load AMScd.js, AMSsymbols.js and unicode.js through the following sequence of steps:
Obtain the .js files for these extensions from the latest MathJax (v2.5) source
Add them to my ~/.ipython/nbextensions
Modify custom.js in ~/.ipython/profile_<mine>/static/custom by appending IPython.load_extensions("AMScd"), etc.
Now, all these work fine, and I am able to typeset commutative diagrams nicely in my IPython notebook. So, while at all this, I decided to also include/load AMSmath.js that comes along with MathJax and this is problematic. (To me, this seems like a natural thing to do given that other extensions work well!) However, attempting to include AMSmath.js via IPython.load_extensions("AMSmath") causes LaTeX math in my Notebook to display [Math Processing Error] everywhere. Here's my minimal example and the output with and without including IPython.load_extensions("AMSmath").
Markup:
## A minimal working example
\\[
\Delta u = f \text{ on } \Omega
\\]
(I would totally like to include images here, alas, my not being an active participant in the community here leaves me with not even 10 reputation!)
So, what am I missing here? Why is this inclusion of AMSmath problematic? Any help would be appreciated! Thanks!
It should work without extra configuration. Have a look here.
Your example in a markdown cell should be
(If you want the equation inline you can use $...$)
Inline equation $\Delta u = f \text{ on } \Omega$
(Or if you want the equation centered in their own line you can use $$...$$)
$$\Delta u = f \text{ on } \Omega$$
The result of both snippets in the same markdown cell is rendered as:
How it is loaded?
IPython/Jupyter notebook preloads some MathJax extensions including the extension you want to load. This extension is not an IPYthon/Jupyter extension so it shouldn't work if you try to load this MathJax extension as an IPython/Jupyter extension. See here to know more about how to load other MathJax extensions.
E.g., I have this Markdown cell that use the sanctioned way of using a LaTeX macro in the notebook
$\def\abc{a\,b\,c}$ The first three letters are $\abc$.
and I have what I want in the notebook. OTOH, when I "Download as PDF via LaTeX"
the conversion process fails with these errors in the standard error of the console
! Undefined control sequence.
l.229 ...c{a\,b\,c}\) The first letters are \(\abc
\).
?
! Emergency stop.
l.229 ...c{a\,b\,c}\) The first letters are \(\abc
\).
! ==> Fatal error occurred, no output PDF file produce
Transcript written on notebook.log.
because Latex itself doesn't accept a definition embedded in a mathematical expression. Because Markdown doesn't accept these definitions outside a mathematical expression I feel like I'm trapped in a Comma 22 situation.
I'm pretty sure the system can be fooled using Raw NBconvert cells and smart latex code but I'm missing some step in my head... Any help will be properly appreciated, ciao
The definition is accepted in the mathematics, but in TeX, definitions are localized to the nearest enclosing group. Math delimiters are enclosing groups, so the definition is remove after the math. Try using \gdef instead of \def to get a global definition. This will require that you load the begingroup extension in MathJax, so you will have to add that to the configuration (I don't know how that is done in IPython, though).
Is it possible to see the output of the TeX ‘pre-processor’, i. e. the intermediate step before the actual output is done but with all user-defined macros replaced and only a subset of TeX primitives left?
Or is there no such intermediate step?
Write
\edef\xxx{Any text with any commands. For example, $\phantom x$.}
And then for output in the log-file
\show\xxx
or for output in your document
\meaning\xxx
There is no "pre-processor" in TeX. The replacement text for any control sequence at any stage can vary (this is used for a lot of things!). For example
\def\demo{\def\demo{cde}}
\demo
will first define \demo in one way and then change it. In the same way, you can redirect TeX primitives. For example, the LaTeX kernel moves \input to an internal position and alters it. A simplified version:
\let\##input\input
\def\input#1{\##input#1 }
Try the Selective Macro Expander.
TeX has a lot of difference tracing tools built in, including tracing macro expansion. This only traces live macros as they are actually expanded, but it's still quite useful. Full details in The TeXbook and probably elsewhere.
When I'm trying to debug a macro problem I generally just use the big hammer:
\tracingall\tracingonline
then I dig in the output or the .log file for what I want to know.
There's a lot of discussion of this issue on this question at tex.SE, and this question. But I'll take the opportunity to note that the best answer (IMO) is to use the de-macro program, which is a python script that comes with TeXLive. It's quite capable, and can handle arguments as well as simple replacements.
To use it, you move the macros that you want expanded into a <something>-private.sty file, and include it into your document with \usepackage{<something>-private}, then run de-macro <mydocument>. It spits out <mydocument>-clean.tex, which is the same as your original, but with your private macros replaced by their more basic things.
When I write math in LaTeX I often need to perform simple arithmetic on numbers in my LaTeX source, like 515.1544 + 454 = ???.
I usually copy-paste the LaTeX code into Google to get the result, but I still have to manually change the syntax, e.g.
\frac{154,7}{25} - (289 - \frac{1337}{42})
must be changed to
154,7/25 - (289 - 1337/42)
It seems trivial to write a program to do this for the most commonly used operations.
Is there a calculator which understand this syntax?
EDIT:
I know that doing this perfectly is impossible (because of the halting problem). Doing it for the simple cases I need is trivial. \frac, \cdot, \sqrt and a few other tags would do the trick. The program could just return an error for cases it does not understand.
WolframAlpha can take input in TeX form.
http://blog.wolframalpha.com/2010/09/30/talk-to-wolframalpha-in-tex/
The LaTeXCalc project is designed to do just that. It will read a TeX file and do the computations. For more information check out the home page at http://latexcalc.sourceforge.net/
The calc package allows you to do some calculations in source, but only within commands like \setcounter and \addtolength. As far as I can tell, this is not what you want.
If you already use sage, then the sagetex package is pretty awesome (if not, it's overkill). It allows you get nicely formatted output from input like this:
The square of
$\begin{pmatrix}
1 & 2 \\
3 & 4
\end{pmatrix}$
is \sage{matrix([[1, 2], [3,4]])^2}.
The prime factorization of the current page number is \sage{factor(\thepage)}
As Andy says, the answer is yes there is a calculator that can understand most latex formulas: Emacs.
Try the following steps (assuming vanilla emacs):
Open emacs
Open your .tex file (or activate latex-mode)
position the point somewhere between the two $$ or e.g. inside the begin/end environment of the formula (or even matrix).
use calc embedded mode for maximum awesomeness
So with point in the formula you gave above:
$\frac{154,7}{25} - (289 - \frac{1337}{42})$
press C-x * d to duplicate the formula in the line below and enter calc-embedded mode which should already have activated a latex variant of calc for you. Your buffer now looks like this:
$\frac{154,7}{25} - (289 - \frac{1337}{42})$
$\frac{-37651}{150}$`
Note that the fraction as already been transformed as far as possible. Doing the same again (C-x * d) and pressing c f to convert the fractional into a floating point number yields the following buffer:
$\frac{154,7}{25} - (289 - \frac{1337}{42})$
$\frac{-37651}{150}$
$-251.006666667$
I used C-x * d to duplicate the formula and then enter embedded mode in order to have the intermediate values, however there is also C-x * e which avoids the duplication and simply enters embedded mode for the current formula.
If you are interested you should really have a look at the info page for Emacs Calc - Embedded Mode. And in general the help for the Gnu Emaca Calculator together with the awesome interactive tutorial.
You can run an R function called Sweave on a (mostly TeX with some R) file that can replace R expressions with their results in Tex.
A tutorial can be found here: http://www.scribd.com/doc/6451985/Learning-to-Sweave-in-APA-Style
My calculator can do that. To get the formatted output, double-click the result formula and press ctrl+c to copy it.
It can do fairly advanced stuff too (differentiation, easy integrals (and not that easy ones)...).
https://calculator-algebra.org/
A sample computation:
https://calculator-algebra.org:8166/#%7B%22currentPage%22%3A%22calculator%22%2C%22calculatorInput%22%3A%22%5C%5Cfrac%7B1%2B2%7D%7B3%7D%3B%20d%2Fdx(arctan%20(2x%2B3))%22%2C%22monitoring%22%3A%22true%22%7D
There is a way to do what you want just not quite how you describe.
You can use the fp package (\usepackage[options]{fp}) the floating point package will do anything you want; solving equations, adding dividing and many more. Unfortunately it will not read the LaTeX math you instead have to do something a little different, the documentation is very poor so I'll give an example here.
for instance if you want to do (2x3)/5 you would type:
\FPmul\p{2}{3} % \p is the assignment of the operation 2x3
\FPupn\p{\p{} 7 round} % upn evaluates the assignment \p and rounds to 7dp
\FPdiv\q{\p}{5} % divides the assigned value p by 5 names result q
\FPupn\q{\q{} 4 round} % rounds the result to 4 decimal places and evaluates
$\frac{2\times3}{5}=\FPprint\q$ % This will print the result of the calculations in the math.
the FP commands are always ibvisible, only FPprint prints the result associated with it so your documents will not be messy, FP commands can be placed wherever you wish (not verb) as long as they are before the associated FPprint.
You could just paste it into symbolab which as a bonus has free step by step solutions. Also since symbolab uses mathquill it instantly formats your latex.
Considering that LaTeX itself is a Turing-complete markup language I strongly doubt you can build something like this that isn't built directly into LaTeX. Furthermore, LaTeX math matkup itself has next to no semantic meaning, it merely describes the visual appearance.
That being said, you can probably hack together something which recognizes a non-programmable subset of LaTeX math markup and spits out the result in the same way. If all you're interested in is simple arithmetics with fractions and integers (careful with decimal fractions, though, as they may appear as 3{,}141... in German texts :)) this shouldn't be too hard. But once you start with integrals, matrices, etc. I fear that LaTeX lacks expressiveness to accurately describe your intentions. It is a document preparation system, after all and thus not very suitable as input for computer algebra systems.
Side note: You can switch to Word which has—in its current version—a math markup language which is sufficiently LaTeX-like (by now it even supports LaTeX markup) and yet still Google-friendly for simpler terms:
With the free Microsoft Math add-in you can even let Word calculate expressions in-place:
There is none, because it is generally not possible.
LaTeX math mode markup is presentational markup and there are cases in which it does not provide enough information to calculate the expression.
That was one of the reasons MathML content markup was created and also why MathML is used in Mathematica. MathML actually is sort of two languages in one:
presentation markup
content markup
To accomplish what you are after you'll have to have MathML with comibned presentation and content markup (see MathML spec).
In my opinion your best bet is to use MathML (even if it is verbose) and convert to LaTeX when necessary. That said, I also like LaTeX syntax best and maybe what we need is a compact syntax for MathML (something similar in spirit to RelaxNG compact syntax).
For calculations with LaTeX you can use a CalcTeX package.
This package understand elements of LaTeX language and makes an calculations, for example your problem is avialble on
http://sg.bzip.pl/CalcTeX/examples/frac.tgz
or just please write
\noindent
For calculation please use following enviromentals
$515.1544 + 454$
or
\[ \frac{154.7}{25}-(289-\frac{1337}{42.})
\]
or
\begin{equation}
154.7/25-(289-1337/42.)
\end{equation}
For more info please visite project web site or contact author of this project.
For performing the math within your LaTeX itself, you might also look into the pgfmath package, which is more powerful and convenient than the calc package. You can find out how to use it from Part VI of The TikZ and PGF Packages Manual, which you can find here (version 2.10 currently): http://mirror.unl.edu/ctan/graphics/pgf/base/doc/generic/pgf/pgfmanual.pdf
Emacs calc-mode accepts latex-input. I use it daily. Press "d", followed by "L" to enter latex input mode. Press "'" to open a prompt where you can paste your tex.
Anyone saing it is not possible is wrong.
IIRC Mathematica can do it.
There is none, because it is generally not possible. LaTeX math mode
markup is presentational markup and there are cases in which it does
not provide enough information to calculate the expression.
You are right. LaTeX as it is does not provide enough info to make any calculations.Moreover, it does not represent any information to do it. But nobody prevents to wright in LaTeX format a text that contains such an information.
It is a difficult path, because you need to build a system of rules superimposed on what content ofthe text in Latex format needs to contain that it would be recognizable by your interpreter. And then convince the user that it is necessary to learn, etc. etc...
The easiest way to create a logical and intuitive calculator of mathematical expressions. And the expression is already possible to convert latex. It's almost like what you said. This is implemented in the program which I have pointed to. AnEasyCalc allows to type an expression as you type the plane text in any text editor. It checks, calculates and generate LateX string by its own then. Its very easy and rapid work. Just try and you will see that.
This is not exactly what you are asking for but it is a nice package
that you can include in a LaTeX document to do all kind of operations including arithmetic, calculus and even vectors and matrices:
The package name is "calculator"
http://mirror.unl.edu/ctan/macros/latex/contrib/calculator/calculator.pdf
The latex2sympy2 Python library can parse LaTeX math expressions.
from latex2sympy2 import latex2sympy
tex_str = r"""YOUR TEX MATH HERE"""
tex_str = r"\frac{9\pi}{\ln(12)}+22" # example TeX math
sympy_object = latex2sympy(tex_str)
evaluated_tex = float(sympy_object.evalf())
print(evaluated_tex)
This Python 3 code evaluates 9𝜋/ln(12)+22 (in its LaTeX from above) to 33.37842899841745.
The snippet above only handles basic algebraic simplification (math expressions without variables). Since the library converts LaTeX math to SymPy objects, the above code can easily be tweaked and extended to handle much more complicated LaTeX math (including solving derivatives, integrals, etc...).
The latex2sympy2 library can be installed via the pip command: pip install --user latex2sympy2
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try the AnEasyCalc program. It allows to get the latex formula very easy:
http://steamandwater.od.ua/AnEasyCalc/
:)