Include apsrtable (or stargazer) output in an Rmd file - windows

Question

I tried to include the summary of an lm object in an Rmd file, using code like the following but it didn't work. Could you help me do that?
```{r summary_lm, results='asis', echo=FALSE, comment=NA}
library(apsrtable)
my_model <- lm(y ~ x, data = data.frame(y = rnorm(10), x = 1:10))
res <- apsrtable(my_model) # my_model is a linear regression model (lm)
cat("$$latex \n",res,"\n$$ \n")
```

Answer 1

The $$ syntax only applies to math expressions, and you were trying to put a table in it, which will not work. The apsrtable, as far as I understand, is for LaTeX only, but LaTeX and Markdown are very different -- there is little hope you can redo LaTeX entirely with Markdown. I think people invented the $$ syntax for Markdown due to the fact that it is well supported by MathJax, and also note there are many variants/flavors based on the original Markdown.
At the moment you may consider:
use the xtable or ascii or R2HTML package to generate HTML tables
request the package author of apsrtable to support HTML tables

Answer 2

What about including my_model in Markdown format with `pander˙:
> library(pander)
> pander(my_model)
--------------------------------------------------------------
Estimate Std. Error t value Pr(>|t|)
----------------- ---------- ------------ --------- ----------
**x** 0.1174 0.1573 0.7465 0.4767
**(Intercept)** -0.2889 0.9759 -0.296 0.7748
--------------------------------------------------------------
Table: Fitting linear model: y ~ x
Or in PHP MarkdownExtra/rmarkdown format:
> panderOptions('table.style', 'rmarkdown')
> pander(my_model)
| | Estimate | Std. Error | t value | Pr(>|t|) |
|:-----------------:|:----------:|:------------:|:---------:|:----------:|
| **x** | 0.1174 | 0.1573 | 0.7465 | 0.4767 |
| **(Intercept)** | -0.2889 | 0.9759 | -0.296 | 0.7748 |
Table: Fitting linear model: y ~ x

Answer 3

Cross-posting my answer to Table of multiple lm() models using apsrtable in Rmarkdown:
It can be done in a pdf_document with apsrtable and also stargazer, which additionally supports HTML.
---
title: "stargazer"
author: "hplieninger"
date: "3 August 2018"
output: pdf_document
header-includes:
- \usepackage{dcolumn}
---
```{r}
m1 <- lm(Fertility ~ Education , data = swiss)
m2 <- lm(Fertility ~ Education + Agriculture, data = swiss)
m3 <- lm(Fertility ~ . , data = swiss)
```
```{r, results='asis'}
apsrtable::apsrtable(m1, m2, m3, Sweave = TRUE)
```
```{r, results='asis'}
# If output: pdf_document
stargazer::stargazer(m1, m2, m3)
# If output: html_document
# stargazer::stargazer(m1, m2, m3, type = "html")
```