Make an art with R

> 👨‍🎨 
>   the programming of aRtdanielle navarro
  
`

Key concepts

lists, tibbles and the $ operator
generating pseudorandom numbers
how to use a while loop
how to use an if statement
making vectors with c()
finessing your pipelines with .
"dplyr" and "ggplot2" revision/extension
introducing the "here" package
a teaser for the "ambient" package

Our studio...

https://rstudio.cloud/project/1112041

Values and Vectors

From the art class...

Four types of value

numeric values: 1.53, 11.6, 1.0, etc
integer values: 0L, 1L, 2L, 100L, etc
character values: "pride", "and", "prejudice",
logical values: TRUE, FALSE

Three kinds of "absence" for a value

NA means "information not available" (e.g., missing data)
NULL means "programming variable doesn't exist"
NaN means "not a number" (e.g., 0/0 is NaN)

Three kinds of "absence" for a value

NA means "information not available" (e.g., missing data)
NULL means "programming variable doesn't exist"
NaN means "not a number" (e.g., 0/0 is NaN)

Two sides to infinity

Inf is positive infinity (e.g., 1/0 is Inf)
-Inf is negative infinity (e.g., -1/0 is -Inf)

Topic:

vectors with c(), numeric
vectors with c(), character
get one using [ ]
get two using [ ]
negative indices drop items
elementwise operations
the recycling rule

Topic:

vectors with c(), numeric
vectors with c(), character
get one using [ ]
get two using [ ]
negative indices drop items
elementwise operations
the recycling rule

Example:

fib <- c(1,1,2,3,5,8)
pet <- c("bat","cat","dog")
pet[3] is "dog"
pet[c(1,3)] is c("bat","dog")
pet[-2] is c("bat","dog")
fib + 1 is c(2,2,3,4,6,9)
fib + c(0,1) is c(1,2,2,4,5,9)

Class and Coercion

From the art class...

Topic:

objects have a class
possibly multiple classes
you can coerce objects...

Topic:

objects have a class
possibly multiple classes
you can coerce objects...

Example:

class(fib) is "numeric"
class(mpg) shows three classes
as.character(3) is "3"
as.character(TRUE) is "TRUE"
as.numeric(TRUE) is 1
as.numeric("cat") is NA

Logical
Operations

Operator:

equal to, ==
less than, <
less than or equal to, <=

Operator:

equal to, ==
less than, <
less than or equal to, <=

Example:

"cat" == "cat" is TRUE
1 < 10 is TRUE
10 <= 10 is TRUE

Operator:

and, &
or, |
not, !

Operator:

and, &
or, |
not, !

Example:

(1+1 == 2) & (2+1 == 2) is FALSE
(1+1 == 2) | (2+1 == 2) is TRUE
!TRUE is FALSE

Lists...

From the art class...

Lists are "containers" for arbitrary objects

art_par <- list(
  seed = c(2, 10, 19),
  n_paths = 100,
  n_steps = 20,
  palette = "bilbao",
  save = TRUE
)

Lists are "containers" for arbitrary objects

art_par <- list(
  seed = c(2, 10, 19),
  n_paths = 100,
  n_steps = 20,
  palette = "bilbao",
  save = TRUE
)

## $seed
## [1]  2 10 19
## 
## $n_paths
## [1] 100
## 
## $n_steps
## [1] 20
## 
## $palette
## [1] "bilbao"
## 
## $save
## [1] TRUE

... Listish
Things?

Tibbles (data frames) are secretly lists

list(
  pet = c("cat", "dog"), 
  count = c(3, 1)
)

## $pet
## [1] "cat" "dog"
## 
## $count
## [1] 3 1

Tibbles (data frames) are secretly lists

list(
  pet = c("cat", "dog"), 
  count = c(3, 1)
)

## $pet
## [1] "cat" "dog"
## 
## $count
## [1] 3 1

tibble(
  pet = c("cat", "dog"), 
  count = c(3, 1)
)

## # A tibble: 2 x 2
##   pet   count
##   <chr> <dbl>
## 1 cat       3
## 2 dog       1

Tibbles (data frames) are secretly lists

list(
  pet = c("cat", "dog"), 
  count = c(3, 1)
)

## $pet
## [1] "cat" "dog"
## 
## $count
## [1] 3 1

data.frame(
  pet = c("cat", "dog"), 
  count = c(3, 1)
)

##   pet count
## 1 cat     3
## 2 dog     1

Loops

iterate code WHILE some condition remains true

value <- 0
while(value < .8) {
  value <- runif(n = 1)
  print(value)
}

iterate code WHILE some condition remains true

value <- 0
while(value < .8) {
  value <- runif(n = 1)
  print(value)
}

## [1] 0.3977455
## [1] 0.1156978
## [1] 0.06974868
## [1] 0.2437494
## [1] 0.7920104
## [1] 0.3400624
## [1] 0.9720625

iterate code FOR each element in a vector

pet <- c("bat","cat","dog")
for(p in pet) {
  msg <- str_c(
    "------", p, "------"
  )
  print(msg) 
}

iterate code FOR each element in a vector

pet <- c("bat","cat","dog")
for(p in pet) {
  msg <- str_c(
    "------", p, "------"
  )
  print(msg) 
}

## [1] "------bat------"
## [1] "------cat------"
## [1] "------dog------"

Executing code IF a condition is true

pet <- c("bat","cat","dog")
for(p in pet) {
  if(p == "cat") {
    msg <- str_c("A ", p, " is the best!!!")
  } 
}
print(msg)

Executing code IF a condition is true

pet <- c("bat","cat","dog")
for(p in pet) {
  if(p == "cat") {
    msg <- str_c("A ", p, " is the best!!!")
  } 
}
print(msg)

## [1] "A cat is the best!!!"

Executing code IF a condition is true

pet <- c("bat","cat","dog")
for(p in pet) {
  if(p == "cat") {
    msg <- str_c("A ", p, " is the best!!!")
  } else {
    msg <- str_c("A ", p, " is okay I guess")
  }
  print(msg) 
}

Executing code IF a condition is true

pet <- c("bat","cat","dog")
for(p in pet) {
  if(p == "cat") {
    msg <- str_c("A ", p, " is the best!!!")
  } else {
    msg <- str_c("A ", p, " is okay I guess")
  }
  print(msg) 
}

## [1] "A bat is okay I guess"
## [1] "A cat is the best!!!"
## [1] "A dog is okay I guess"

↑, ←, Pg Up, k	Go to previous slide
↓, →, Pg Dn, Space, j	Go to next slide
Home	Go to first slide
End	Go to last slide
Number + Return	Go to specific slide
b / m / f	Toggle blackout / mirrored / fullscreen mode
c	Clone slideshow
p	Toggle presenter mode
t	Restart the presentation timer
?, h	Toggle this help

> 👨‍🎨 > the programming of aRt

danielle navarro

https://rstudio.cloud/project/1112041

Help

> 👨‍🎨
> the programming of aRt