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   "roxygen-guidelines.Rmd",
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+  "shiny-ci-cd.Rmd",
+  "xlconnect.Rmd"
   ]
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+# Control Microsoft Excel interface with `XLConnect`
+
+```{r setup, include=FALSE}
+knitr::opts_chunk$set(echo = TRUE, collapse = TRUE, eval = FALSE)
+```
+
+MS Excel is probably the most used support to share data analysis and reports in many organizations. However there is a good chance that you will prefer to perform most of the steps of your data analysis and reporting in R and just present and share the results in Excel. Using the package [`XLConnect`](https://github.com/miraisolutions/xlconnect) will allow you to read, write and manipulate MS Excel files from within R.
+
+XLConnect's main features:
+
+- read & write Excel worksheets & named ranges
+
+- create, remove, rename, clone & hide/ unhide worksheets
+
+- add graphs
+
+- specify/ use cell styles, column width & row height
+
+- define behavior when error cells are encountered, formula recalculation when workbooks are opened
+
+- others: merge/unmerge cells, set auto-filters etc.
+
+## Installation
+
+XLConnect is cross-platform and runs in all operating systems that support Java. Besides R and a JRE (Java Runtime Environment), nothing else is needed, even an installation of MS Excel is NOT required.
+
+```{r , echo = TRUE, eval = FALSE}
+# Install XLConnect
+install.packages("XLConnect")
+
+# Load XLConnect and get ready to use XLConnect package
+require(XLConnect)
+```
+
+## Basic functions: write & read an Excel sheet
+
+### Writing Excel files
+
+```{r , echo = TRUE, eval = FALSE}
+# Load Excel workbook - either .xls or .xlsx. Create if not existing
+wb <- loadWorkbook("xlconnect-demo/XLConnectDemo.xlsx", create = TRUE)
+
+# Create a Sheet within an Excel workbook
+createSheet(wb, name = "CHF")
+
+# Write into a sheet
+# Write Swiss Francs data frame into CHF sheet
+writeWorksheet(wb, swissfranc, sheet = "CHF", startRow = 2, startCol = 2)
+
+# Save workbook - this actually writes the file
+saveWorkbook(wb)
+```
+
+The steps above can be executed in a single call using the `writeWorksheetToFile()` function.
+```{r , echo = TRUE, eval = FALSE}
+# Write and save a data frame into a specific sheet of a workbook
+writeWorksheetToFile("xlconnect-demo/XLConnectDemo.xlsx", 
+                     data = swissfranc, sheet = "OneCall", 
+                     startRow = 2, startCol = 2)
+```
+
+The data frame can also be written in a named region using the single call `writeNamedRegionToFile()` function.
+```{r , echo = TRUE, eval = FALSE}
+# Write and save a data frame into a specific named region of a workbook
+writeNamedRegionToFile("xlconnect-demo/XLConnectDemo.xlsx", 
+                       data = swissfranc, name = "SwissFrancName", 
+                       formula = "NamedRegionEx!$B$2")
+```
+
+### Reading from  Excel files
+
+```{r , echo = TRUE, eval = FALSE}
+# Load Excel workbook - either .xls or .xlsx. Create if not existing.
+wb <- loadWorkbook("xlconnect-demo/XLConnectDemo.xlsx", create = TRUE)
+
+# Read data from a specific sheet of a workbook
+dataFromExcel <- readWorksheet(wb, sheet = "CHF")
+
+# Read data from a specific location in a sheet of a workbook
+dataFromExcel <- readWorksheet(wb, 
+                               sheet = "CHF", 
+                               startRow = 2, endRow = 10,
+                               startCol = 2, endCol = 5, 
+                               header = TRUE)
+```
+
+The steps above can be executed in a single call using the `readWorksheetFromFile()` function.
+```{r , echo = TRUE, eval = FALSE}
+# Read data from a specific location in a sheet of a workbook
+dataFromExcel <- readWorksheetFromFile("xlconnect-demo/XLConnectDemo.xlsx", 
+                                       sheet = "OneCall", 
+                                       startRow = 2, endRow = 10, 
+                                       startCol = 2, endCol = 5, 
+                                       header = TRUE)
+```
+
+The data can also be read from an existing named region using the single call `readNamedRegionFromFile()` function.
+```{r , echo = TRUE, eval = FALSE}
+# Read data from a specific named region of a workbook
+dataFromExcel <- readNamedRegionFromFile("xlconnect-demo/XLConnectDemo.xlsx", 
+                                         name = "SwissFrancName", 
+                                         header = TRUE)
+```
+
+It can be useful to retrieve all the sheets of a workbook or all existing named ranges.
+```{r , echo = TRUE, eval = FALSE}
+# Get all sheet names of a workbook
+allSheets <- getSheets(wb)
+
+# Get all named regions of a workbook
+allnr <- getDefinedNames(wb)
+```
+
+## Formatting
+
+### Create and apply some formatting
+Now let's try out some formatting functionality.
+
+```{r , echo = TRUE, eval = FALSE}
+# Load file
+wb <- loadWorkbook("xlconnect-demo/XLConnectDemo.xlsx", create = TRUE)
+# Apply data format only - depending on the data type
+setStyleAction(wb, XLC$STYLE_ACTION.DATA_FORMAT_ONLY)
+
+# Set format for numeric data to 2 decimal digits
+setDataFormatForType(wb, type = XLC$DATA_TYPE.NUMERIC, format = "0.00")
+
+# Write the named region
+writeNamedRegion(wb, data = swissfranc, name = "SwissFrancName")
+
+# Create a cell style for the headers
+csHeader <- createCellStyle(wb, name = "StyleHeader")
+setFillPattern(csHeader, fill = XLC$FILL.SOLID_FOREGROUND)
+setFillForegroundColor(csHeader, color = XLC$COLOR.CORNFLOWER_BLUE)
+setCellStyle(wb, sheet = "NamedRegionEx", 
+             row = 2, col = seq(2, ncol(swissfranc) + 1), 
+             cellstyle = csHeader)
+
+# Set an auto-filter
+setAutoFilter(wb, sheet = "NamedRegionEx", 
+              reference = aref("B2", dim(swissfranc)))
+
+
+# Create a custom format for the date column
+csDate <- createCellStyle(wb, name = "StyleDate")
+setDataFormat(csDate, format = "yyyy-mm-dd")
+setCellStyle(wb, sheet = "NamedRegionEx", 
+             row = seq(3, nrow(swissfranc) + 2), 
+             col = 2, 
+             cellstyle = csDate)
+
+# Enlarge column "date" to fit full information
+setColumnWidth(wb, sheet = "NamedRegionEx", 
+               column = 2, width = 2800)
+
+
+# Save workbook - this actually writes the file
+saveWorkbook(wb)
+```
+
+### Retrieve and apply some formatting
+
+Intermediate step to make a copy of the template.
+
+```{r , echo = TRUE, eval = FALSE}
+# Create a copy of the template
+file.copy("xlconnect-demo/XLConnectDemo-Tpl.xlsx", 
+          "xlconnect-demo/XLCDemo-TplCopy.xlsx", 
+          overwrite = FALSE)
+wbcopy <- loadWorkbook("xlconnect-demo/XLCDemo-TplCopy.xlsx")
+saveWorkbook(wbcopy)
+```
+
+Add a new sheet in the copied file and use defined formatting from the template.
+
+```{r , echo = TRUE, eval = FALSE}
+# Create a dummy input sheet
+writeWorksheetToFile("xlconnect-demo/XLCDemo-TplCopy.xlsx", 
+                     data = data.frame("Titles" = c("Dummy Input", "Exchange Rate CHF/Curr")), 
+                     sheet = "Input", 
+                     startRow = 2, startCol = 2, header = FALSE)
+
+# Get some data from the previous file
+# Read data from a specific named region of a workbook
+if(exists("xlconnect-demo/XLConnectDemo.xlsx")) {
+  dataToReuse <- readNamedRegionFromFile("xlconnect-demo/XLConnectDemo.xlsx", 
+                                         name = "SwissFrancName", 
+                                         header = TRUE)
+} else {
+  dataToReuse <- swissfranc
+}
+
+# Add data in a named region
+writeNamedRegionToFile("xlconnect-demo/XLCDemo-TplCopy.xlsx", 
+                       data = dataToReuse, name = "SwissFrancName", 
+                       formula = "Input!$B$5")
+
+# Retrieve formatting from existing cell style names from the template copy
+wbcopy <- loadWorkbook("xlconnect-demo/XLCDemo-TplCopy.xlsx")
+cstitle1 <- getCellStyle(wbcopy, "Title1")
+cstitle2 <- getCellStyle(wbcopy, "Title2")
+csTableHeader <- getCellStyle(wbcopy, "TableHeader")
+csinp <- getCellStyle(wbcopy, "Inp")
+cscalc <- getCellStyle(wbcopy, "Calc")
+
+# Apply formatting - This has to be in the same file
+setCellStyle(wbcopy, 
+             formula = "Input!$B$2:$B$2", 
+             cellstyle = cstitle1)
+setCellStyle(wbcopy, 
+             formula = "Input!$B$3:$B$3", 
+             cellstyle = cstitle2)
+setCellStyle(wbcopy, 
+             formula = "Input!$C$5:$E$425", 
+             cellstyle = csinp)
+setCellStyle(wbcopy, 
+             formula = "Input!$B$5:$B$425", 
+             cellstyle = cscalc)
+if(!existsCellStyle(wbcopy, "csDate")){
+  csDate <- createCellStyle(wbcopy, name = "DateFormat")
+  setDataFormat(csDate, format = "yyyy-mm-dd")
+}
+setCellStyle(wbcopy, sheet = "Input", 
+             row = 5:425, 
+             col = 2, 
+             cellstyle = csDate)
+
+# Save workbook - this actually writes the file
+saveWorkbook(wbcopy)
+```
+
+## Add a graph
+
+First, create an image out of a graph
+```{r , echo = TRUE, eval = FALSE}
+# Load the demo file
+wb <- loadWorkbook("xlconnect-demo/XLConnectDemo.xlsx", create = TRUE)
+
+# Prepare object
+currencies <- names(swissfranc)[-1]
+gcurr <- reshape(swissfranc, 
+                 varying = currencies, 
+                 direction = "long", 
+                 v.names = "Value", 
+                 times = currencies, 
+                 timevar = "Currency")
+# Use ggplot2 to create a graph
+require(ggplot2)
+p <- ggplot(gcurr, aes(Date, Value, colour = Currency)) +
+  geom_line() + stat_smooth(method = "loess") +
+  scale_y_continuous("Exchange Rate CHF/Curr") +
+  labs(title = paste0("CHF vs ", paste(currencies, collapse = ", ")), x = "") + 
+  theme(axis.title.y = element_text(size = 10, angle = 90, vjust = 0.3))
+print(p)
+# Save plot to as a png
+dev.copy(png, "swissfrancplot.png")
+dev.off()
+```
+
+Then, add the image to the output file
+```{r , echo = TRUE, eval = FALSE}
+# Define the location in the output file
+createName(wb, name = "graph", formula = "NamedRegionEx!$H$2")
+# Add image to the file
+addImage(wb, 
+         filename = "xlconnect-demo/swissfrancplot.png", 
+         name = "graph", 
+         originalSize = TRUE)
+
+saveWorkbook(wb)
+```
+
+
+## Other functionaly 
+
+Let's perform some usual tasks on a template and use few more interesting XLConnect functionality like:
+
+- ensure values get updated when opening a workbook
+
+- check if a sheet is visible
+
+- check if a named region exists
+
+- hide or unhide  sheets
+
+- append a named region
+
+- find out the coordinates of a named region in a sheet
+
+- additional formatting like setting the column width
+
+- remove sheets and named region
+
+- clone sheet
+
+- add hyperlink
+
+### Recalculate workbook
+Reading....
+```{r , echo = TRUE, eval = FALSE}
+if (!exists("xlconnect-demo/XLCDemo-TplCopy.xlsx")){
+  # Create a copy of the template
+  file.copy("xlconnect-demo/XLConnectDemo-Tpl.xlsx", 
+          "xlconnect-demo/XLCDemo-TplCopy.xlsx", 
+          overwrite = FALSE)
+} 
+# Load copy of the template
+wbcopy <- loadWorkbook("xlconnect-demo/XLCDemo-TplCopy.xlsx")
+
+# Read data from template copy using named regions
+inc_df <- readNamedRegion(wbcopy,
+                          name = "Income_inp",
+                          header = TRUE)
+persexp_df <- readNamedRegion(wbcopy,
+                          name = "PersExpenses_inp",
+                          header = TRUE)
+opexp_df <- readNamedRegion(wbcopy,
+                          name = "OpExpenses_inp",
+                          header = TRUE)
+# Update numbers: double sales
+inc_df$ACTUAL[inc_df$INCOME == "Net sales"] <- inc_df$ACTUAL[inc_df$INCOME == "Net sales"] * 2
+# Update numbers: add employee benefits
+persexp_df$ACTUAL[persexp_df$PERSONNEL.EXPENSES == "Employee benefits"] <- 3000
+#  Update numbers: reduce maintenance
+opexp_df$ACTUAL[opexp_df$OPERATING.EXPENSES == "Maintenance and repairs"] <- 2500
+```
+
+Writing...
+```{r , echo = TRUE, eval = FALSE}
+# Update output accordingly
+writeNamedRegion(wbcopy, Sys.Date(), "Date", header = FALSE)
+writeNamedRegion(wbcopy, inc_df, "Income_out", header = FALSE)
+writeNamedRegion(wbcopy, persexp_df, "PersExpenses_out", header = FALSE)
+writeNamedRegion(wbcopy, opexp_df, "OpExpenses_out", header = FALSE)
+
+# Get numbers of sheets
+nb_sheets <- length(getSheets(wbcopy))
+# Force Excel to re-calculate when opening the workbook
+setForceFormulaRecalculation(wbcopy, sheet = seq(1, nb_sheets), TRUE)
+# Save workbook - this actually writes the file
+saveWorkbook(wbcopy)
+```
+
+### Hide sheets
+Hide irrelevant sheets
+```{r , echo = TRUE, eval = FALSE}
+# Hide sheets
+sheetsToHide <- c("Style","Input")
+# Ensure those sheets exist in the workbook
+sheetsToHide <- sheetsToHide[sheetsToHide %in% getSheets(wbcopy)]
+hideSheet(wbcopy, sheetsToHide, veryHidden = TRUE)
+# Save workbook - this actually writes the file
+saveWorkbook(wbcopy)
+```
+
+### Sheet visibility check and unhide sheets 
+Check if a sheet is visible and unhide sheet
+```{r , echo = TRUE, eval = FALSE}
+# Check if a sheet is visible
+if (!isSheetVisible(wbcopy, c("Review"))) {
+  # Unhide sheet
+  unhideSheet(wbcopy, "Review")
+}
+# Save workbook - this actually writes the file
+saveWorkbook(wbcopy)
+```
+
+### Append named region
+Check if a named region exists & append named region
+```{r , echo = TRUE, eval = FALSE}
+# Check if a named region exists
+if (existsName(wbcopy, c("Review"))) {
+  # Create a new entry to append
+  newreview_df <- data.frame(Reviewer = c("Sam Tire"), 
+                             Function = c("Accounting Reviewer"), 
+                             Date = Sys.Date())
+  # Ensure column matches
+  if (!all(colnames(newreview_df) == colnames(readNamedRegion(wbcopy, "Review")))) {
+    stop("table to populate does not match expected header, column names and order must match")
+  }
+  # Append existing named region
+  appendNamedRegion(wbcopy, newreview_df, name = "Review")
+  csinp <- getCellStyle(wbcopy, "Inp")
+  
+  # Get position of a named region in a Excel file
+  review_pos <- getReferenceCoordinatesForName(wbcopy, "Review")
+  colStart_pos <- LETTERS[review_pos[1,2]]
+  colEnd_pos <- LETTERS[review_pos[2,2]]
+  # Apply cell formatting
+  setCellStyle(wbcopy, 
+             formula = paste0("Review!", colStart_pos, "$", review_pos[1,1] + 1, ":$", colEnd_pos, review_pos[2,1]),
+             cellstyle = csinp)
+  
+  if(!existsCellStyle(wbcopy, "Format-Date")){
+    # Create a custom format for the date column
+    csDate <- createCellStyle(wbcopy, name = "Format-Date")
+    setDataFormat(csDate, format = "yyyy-mm-dd")
+  }
+  setCellStyle(wbcopy, sheet = "Review", 
+             row = seq(review_pos[1,1] + 1, review_pos[2,1]), 
+             col = review_pos[2,2], 
+             cellstyle = csDate)
+  # Enlarge column date
+  setColumnWidth(wbcopy, sheet = "Review", column = review_pos[2,2], width = 4000 )
+  # Save workbook - this actually writes the file
+  saveWorkbook(wbcopy)
+}
+```
+
+### Remove sheets
+Delete sheets
+```{r , echo = TRUE, eval = FALSE}
+# Create a new copy
+file.copy("xlconnect-demo/XLCDemo-TplCopy.xlsx", 
+          "xlconnect-demo/XLCDemo-Input.xlsx", 
+          overwrite = FALSE)
+# Load new copy
+wbinput <- loadWorkbook("xlconnect-demo/XLCDemo-Input.xlsx")
+
+# Unhide sheet - if goal is to remove all sheets but "input" then has to be visible
+unhideSheet(wbinput, "Input")
+
+# Remove all sheets of the copy but "input"
+wbinput_allsheets <- getSheets(wbinput)
+removeSheet(wbinput, wbinput_allsheets[!(wbinput_allsheets %in% c("Input"))])
+saveWorkbook(wbinput)
+```
+
+### Remove named regions
+Delete Named Regions
+```{r , echo = TRUE, eval = FALSE}
+# Load new copy
+wbinput <- loadWorkbook("xlconnect-demo/XLCDemo-Input.xlsx")
+# Remove all named regions of the copy but "SwissFrancName"
+wbinput_allnr <- getDefinedNames(wbinput)
+removeName(wbinput, wbinput_allnr[!(wbinput_allnr %in% c("SwissFrancName"))])
+
+saveWorkbook(wbinput)
+```
+
+### Clone sheets
+Clone Sheet
+```{r , echo = TRUE, eval = FALSE}
+# Load new copy
+wbinput <- loadWorkbook("xlconnect-demo/XLCDemo-Input.xlsx") 
+# Ensure sheet exists
+if(existsSheet(wbinput, "Input")){
+  # Clone sheet
+  cloneSheet(wbinput, sheet = "Input", name = "clonedSheet")
+  saveWorkbook(wbinput)
+}
+```
+
+### Clear sheets
+Clear a sheet can be useful if data sets in a worksheet need to be replaced in a smaller range as the original data.
+```{r , echo = TRUE, eval = FALSE}
+# Load new copy
+wbinput <- loadWorkbook("xlconnect-demo/XLCDemo-Input.xlsx") 
+if(existsSheet(wbinput, "clonedSheet")){
+  # clear sheet
+  clearSheet(wbinput, sheet = "clonedSheet")
+  saveWorkbook(wbinput)
+}
+```
+
+### Add hyperlinks
+Write an hyperlink
+```{r , echo = TRUE, eval = FALSE}
+# Load new copy
+wbinput <- loadWorkbook("xlconnect-demo/XLCDemo-Input.xlsx") 
+if(existsSheet(wbinput, "clonedSheet")){
+  # Add hyperlink
+  writeWorksheet(wbinput, data.frame(Company = "Mirai Solution"), sheet = "clonedSheet", startRow = 1, startCol = 2)
+  mirai_web <- "https://mirai-solutions.ch/"
+  setHyperlink(wbinput, 
+               sheet = "clonedsheet", 
+               row = 2, col = 2, 
+               type = XLC$HYPERLINK.URL, 
+               address = mirai_web)
+  saveWorkbook(wbinput)
+}
+```
+
+### Merge/ Unmerge cells
+Merge cells
+```{r , echo = TRUE, eval = FALSE}
+# Load new copy
+wbinput <- loadWorkbook("xlconnect-demo/XLCDemo-Input.xlsx") 
+if(existsSheet(wbinput, "clonedSheet")){
+  # Merge cells - to unmerge, use the similar function 'unmergeCells()'
+  mergeCells(wbinput, sheet = "clonedsheet", reference = "B2:C2")
+  saveWorkbook(wbinput)
+}
+```
+
+### Clean up
+Clean up and remove the demo files
+```{r , echo = TRUE, eval = FALSE}
+# Remove file
+file.remove("xlconnect-demo/XLConnectDemo.xlsx")
+file.remove("xlconnect-demo/XLCDemo-TplCopy.xlsx")
+file.remove("xlconnect-demo/XLCDemo-Input.xlsx")
+```