### -----------------------------------------------------------------------
### Autor: Paul Fink, et. al. (Stand: SoSe 2017)
### -----------------------------------------------------------------------


## ----print1--------------------------------------------------------------
X <- matrix(data = sqrt(2:7), nrow = 3, ncol = 2, byrow = TRUE)
print(X)

## ----printdigit----------------------------------------------------------
print(sqrt(2))
print(sqrt(2), digits = 2)
print(sqrt(2), digits = 4)
print(sqrt(2) + 100, digits = 2)
print(sqrt(2) + 100, digits = 4)

## ----cat-----------------------------------------------------------------
v <- 7
cat("Quadrat von", v, ":", v^2, "!\n")
cat("Quadrat von ", v, ": ", v^2, "!\n", sep = "")

## ----paste-basis---------------------------------------------------------
pa <- paste("Aufgabe", 1:5, "a", sep = "_")
pa
pa[1]

## ----paste-collapse------------------------------------------------------
pac <- paste(pa, collapse = "?")
pac

## ----strsplit-basis------------------------------------------------------
x <- "Die Syntax#!von strsplit#!findet man!#wie immer!#in der Hilfe"
strsplit(x, split = "#")
spl <- strsplit(x, split = "!#")
spl

## ----strsplit-regexp-----------------------------------------------------
strsplit(pac, "?")

## ----strsplit-regexp-fixed-----------------------------------------------
strsplit(pac, "?", fixed = TRUE)

## ----suchen--------------------------------------------------------------
grep("#!", c(x, pac) )# "#!" ist im 1-ten Element, also in x
grepl("#!", c(x, pac) )

## ----ersetzen------------------------------------------------------------
sub("#!", " ", x) # Nur das erste Vorkommen
gsub("#!", " ", x) # Alle Vorkommen

## ----ersetzen-regexp-----------------------------------------------------
gsub("?", " ", pac)
gsub("?", " ", pac, fixed = TRUE)

## ----regulaererAusdruck--------------------------------------------------
z <- "           Viele Leerzeichen am Anfang"
z
gsub("^\\s*", "", z) # Loeschen der Leerzeichen am Anfang

## ----aufgabe-laden-daten-------------------------------------------------
## load(url("https://moodle.lmu.de/mod/resource/view.php?id=70483"))