Insert multiple images into for-loop in Sweave Document

I have five images stored as follows (where "currentDirectory" is the output I get from the getwd () command):

currentDirectory/results/thePlot_1.jpg
currentDirectory/results/thePlot_2.jpg
currentDirectory/results/thePlot_3.jpg
currentDirectory/results/thePlot_4.jpg
currentDirectory/results/thePlot_5.jpg

      

        
        
        
      

    

I am trying to write a .Rnw script in Rstudio that will create a .tex file which I can then run pdflatex to have a .pdf file containing these five images. Below I have tried:

\documentclass{article}
\usepackage{float, hyperref}
\usepackage[margin=1in]{geometry}
\usepackage{graphicx}
\usepackage{hyperref}
\usepackage{caption}
\usepackage{algorithm}
\usepackage{algorithmic}

\begin{document}
\SweaveOpts{concordance=TRUE}

\author{myName}
\title{myTitle}

\maketitle

<<options, echo=FALSE>>=
library(knitr)
  opts_chunk$set(cache=TRUE)
@

\section*{mySection}

\FOR{i in 1:5}
nPlots=i
plotName = "thePlot"
outDir = "results"
\includegraphics{paste(getwd(), "/", outDir , "/", plotName, "_", i, sep="")}
\ENDFOR

\end{document}

      

        
        
        
      

    

For which I am getting multiple errors:

Line 25: Undefined control sequence. Line 29: Missing $ value. Line 29: LaTeX error: File `paste (getwd ()," / ", outDir," / ", plotName," _ ", i, sep =" ") 'not found. Line 29: Missing $ value. Line 30: The escape sequence is Undefined.

Any help is greatly appreciated!

EDIT 1: I took Alex A.'s advice into account and changed the section to include the \ Sexpr {} expressions as follows:

\FOR{i in 1:5}
\Sexpr{nPlots=i}
\Sexpr{plotName = "thePlot"}
\Sexpr{outDir = "results"}
\includegraphics{\Sexpr{paste(getwd(), "/", outDir , "/", plotName, "_", i, sep="")}}
\ENDFOR

\end{document}

      

        
        
        
      

    

However, I am now getting the error:

object 'i' not found

      

        
        
        
      

    

I tried changing the condition in the for loop to include \ Sexpr {} as well, as in:

\FOR{\Sexpr{i in 1:5}}

      

        
        
        
      

    

But this is throwing me an error:

Unexpected 'in'

      

        
        
        
      

    

Any help is appreciated!

EDIT 2:

I tried to heed the advice to just enable for-loop and image insertion in Rcode. So I tried using jpeg library and my readJPEG method as below:

<<echo=FALSE>>==
library(jpeg)
@

<<plots, echo = FALSE, fig = TRUE, figs.only = TRUE, results = hide>>=
for (i in 1:5){
  nPlots=i
  plotName = "thePlot"
  outDir = "results"

  img <- readJPEG(paste(getwd(), "/", outDir , "/", plotName, "_", i, ".jpg", sep=""))
  plot(img)
}
@

\end{document}

      

        
        
        
      

    

Unfortunately this still results in an error:

Unexpected 'in'

      

        
        
        
      

    

Also, when I run just one below code (not in for-loop or .Rnw file):

  nPlots=1
  plotName = "thePlot"
  outDir = "results"

  img <- readJPEG(paste(getwd(), "/", outDir , "/", plotName, "_", i, ".jpg", sep=""))
  plot(img)

      

        
        
        
      

    

The image that generates looks different than the .jpeg image I have (located in currentDirectory / results / thePlot_1.jpg)