Rmarkdown not building model equation to word - r

Question

This is my code for linear model
model = lm(UCBRpk~ pksa + dist)
summary(model)
equatiomatic::extract_eq(model,wrap = TRUE)
equatiomatic::extract_eq(model, wrap = TRUE,use_coefs = TRUE)
I got the equation when knitting to html and pdf, but unable in word
This is the usual error message each time I knit to word:
unexpected "&"
expecting "%", "\\label", "\\nonumber" or whitespace
[WARNING] Could not convert TeX math '
\begin{aligned}
\operatorname{\widehat{SCBRcp}} &= 43.34 + 3.53(\operatorname{cpa}_{\operatorname{10\%}}) + 2.68(\operatorname{cpa}_{\operatorname{2\%}}) + 4.67(\operatorname{cpa}_{\operatorname{4\%}})\ + \\
&\quad 8.9(\operatorname{cpa}_{\operatorname{6\%}}) + 6.24(\operatorname{cpa}_{\operatorname{8\%}}) + 3.15(\operatorname{dist}_{\operatorname{A2}}) - 1.81(\operatorname{dist}_{\operatorname{A3}})
\end{aligned}
', rendering as TeX:
d}

Answer 1

tldr;
Seems like a bug with equatiomatic; I recommend opening an issue.
The issue is with the \operatorname calls in the LaTeX code produced by equatiomatic. I don't know whether the culprit is MathJax (since the expression itself is valid LaTeX) but a more minimal example reproducing your issue is as follows:
---
title: "Untitled"
output: word_document
---
$$
\begin{aligned}
\operatorname{\widehat{x}} &= a + b\ + \\
&\quad c + d
\end{aligned}
$$
which upon knitting produces the following warning
[WARNING] Could not convert TeX math '
\begin{aligned}
\operatorname{\widehat{x}} &= a + b\ + \\
&\quad c + d
\end{aligned}
', rendering as TeX:
ligned}
^
unexpected "&"
expecting "%", "\\label", "\\nonumber" or whitespace
I am not familiar with equatiomatic but in my (LaTeX) opinion, the translation of those equations into LaTeX should use \mathrm rather than \operatorname (see e.g. What's the difference between \mathrm and \operatorname? for a discussion and examples on how these two differ; amongst other things, \operatorname treats punctuation symbols like text whereas \mathrm treats them as math symbols. Perhaps -- and I'm 100% speculating here -- that's the reason why the equatiomatic devs decided to use \operatorname rather than \mathrm).
If I replace all \operatorname calls with \mathrm your example expression compiles fine.
---
title: "Untitled"
output: word_document
---
$$
\begin{aligned}
\mathrm{\widehat{SCBRcp}} &= 43.34 + 3.53(\mathrm{cpa}_{\mathrm{10\%}}) + 2.68(\mathrm{cpa}_{\mathrm{2\%}}) + 4.67(\mathrm{cpa}_{\mathrm{4\%}})\ + \\
&\quad 8.9(\mathrm{cpa}_{\mathrm{6\%}}) + 6.24(\mathrm{cpa}_{\mathrm{8\%}}) + 3.15(\mathrm{dist}_{\mathrm{A2}}) - 1.81(\mathrm{dist}_{\mathrm{A3}})
\end{aligned}
$$
So long story short, what can you do? Other than manually editing the output of equatiomatic I recommend opening an issue on the equatiomatic GH site, and cross-linking to this post on Stack Overflow.