Chapter 3 Introdução relâmpago de R

Como a seção já sugere, segue alguns comandos básicos para conseguirmos acompanhar o curso.

# -----------------------------------------------------------------------------
# Como instalar pacotes
# -----------------------------------------------------------------------------
#install.packages('descr')

# -----------------------------------------------------------------------------
# Como remover pacotes
# ----------------------------------------------------------------------------- 
#remove.packages('descr')

# -----------------------------------------------------------------------------
# Carregar e listar os conteúdos dos pacotes
# -----------------------------------------------------------------------------
library(fdth)

# -----------------------------------------------------------------------------
# Ajuda (socorro)
# -----------------------------------------------------------------------------
help(round)#ou de modo mais simplificado
?round

# -----------------------------------------------------------------------------
# Operadores de atribuição
# -----------------------------------------------------------------------------
# <- 
# ->
# =
a <- 1
2 -> b
c = 3

# -----------------------------------------------------------------------------
# Imprimir no console uma mensagem ou o valor de uma variável:
# -----------------------------------------------------------------------------
print(a) # ou simplesmente

## [1] 1

a

## [1] 1

# -----------------------------------------------------------------------------
# Operadores matemáticos
# -----------------------------------------------------------------------------
# + soma
# - subtração
# * multiplicação
# / divisão
# ^ potenciação
# %% operador modular

2 + 1

## [1] 3

3 - 5

## [1] -2

3 * 9

## [1] 27

4/8

## [1] 0.5

5^(1 + 1)

## [1] 25

5^1 + 1

## [1] 6

6 * (5 + 3)

## [1] 48

3%%2

## [1] 1

4%%2

## [1] 0

5%%2

## [1] 1

# -----------------------------------------------------------------------------
# Vetores
# -----------------------------------------------------------------------------
# Algumas das diversas formas de criar:

#c() - é uma função
# vetores numéricos
c(1.54, 1.75, 1.60, 1.60, 1.73, 1.63, 1.52, 1.79, 1.64, 1.60, 1.60, 1.61, 1.59, 1.77)

##  [1] 1.54 1.75 1.60 1.60 1.73 1.63 1.52 1.79 1.64 1.60 1.60 1.61 1.59
## [14] 1.77

altura = c(1.54, 1.75, 1.60, 1.60, 1.73, 1.63, 1.52, 1.79, 1.64, 1.60, 1.60, 1.61, 1.59, 1.77)
altura

##  [1] 1.54 1.75 1.60 1.60 1.73 1.63 1.52 1.79 1.64 1.60 1.60 1.61 1.59
## [14] 1.77

peso = c(56, 73, 50, 70, 57, 55, 78, 50)
peso

## [1] 56 73 50 70 57 55 78 50

mean(peso)

## [1] 61.125

var(peso)

## [1] 118.9821

sd(peso)

## [1] 10.90789

hist(peso)

# vetores de strings
c('coca', 'pepsi') # pode criar um vetor com strings

## [1] "coca"  "pepsi"

estcivil = c('solt','solt','casad','solt','casad',"solt")
estcivil

## [1] "solt"  "solt"  "casad" "solt"  "casad" "solt"

# Algumas formas de indexar (índices):
x = seq(1,20,by = 2)
x

##  [1]  1  3  5  7  9 11 13 15 17 19

x[2]

## [1] 3

# -----------------------------------------------------------------------------
# Data Frames
# -----------------------------------------------------------------------------
x = rnorm(10,
          10,
          2)
x

##  [1] 10.659016  8.359063 10.974858 11.476649 11.151563  9.389223
##  [7] 13.023562 10.779686  8.757519  5.570600

class(x)          

## [1] "numeric"

y = letters[1:10]
y

##  [1] "a" "b" "c" "d" "e" "f" "g" "h" "i" "j"

class(y)

## [1] "character"

mean(y)

## Warning in mean.default(y): argumento não é numérico nem lógico:
## retornando NA

## [1] NA

sexo = c('f','f','m','f','m','m','m','m','m','f')

#data.frame()
dF = data.frame(x,
                y,
                sexo)
dF

##            x y sexo
## 1  10.659016 a    f
## 2   8.359063 b    f
## 3  10.974858 c    m
## 4  11.476649 d    f
## 5  11.151563 e    m
## 6   9.389223 f    m
## 7  13.023562 g    m
## 8  10.779686 h    m
## 9   8.757519 i    m
## 10  5.570600 j    f

class(dF)

## [1] "data.frame"

# A instrução 'summary' sumariza um objeto (aqui, um frame, mas vai bem com
# quase todos objetos):
summary(dF)

##        x               y                 sexo          
##  Min.   : 5.571   Length:10          Length:10         
##  1st Qu.: 8.915   Class :character   Class :character  
##  Median :10.719   Mode  :character   Mode  :character  
##  Mean   :10.014                                        
##  3rd Qu.:11.107                                        
##  Max.   :13.024

## Indexação!
# Opção 1
dF$x

##  [1] 10.659016  8.359063 10.974858 11.476649 11.151563  9.389223
##  [7] 13.023562 10.779686  8.757519  5.570600

dF$y

##  [1] "a" "b" "c" "d" "e" "f" "g" "h" "i" "j"

# Opção 2
dF[ ,1]

##  [1] 10.659016  8.359063 10.974858 11.476649 11.151563  9.389223
##  [7] 13.023562 10.779686  8.757519  5.570600

dF[ ,2]

##  [1] "a" "b" "c" "d" "e" "f" "g" "h" "i" "j"

dF[3:5,1]

## [1] 10.97486 11.47665 11.15156

# Pode-se mudar o nome das linhas ou das colunas:
names(dF) = c('ivan',
              'joao',
              'leila')
dF

##         ivan joao leila
## 1  10.659016    a     f
## 2   8.359063    b     f
## 3  10.974858    c     m
## 4  11.476649    d     f
## 5  11.151563    e     m
## 6   9.389223    f     m
## 7  13.023562    g     m
## 8  10.779686    h     m
## 9   8.757519    i     m
## 10  5.570600    j     f

# Opção melhor
with(dF,
     mean(x))

## [1] 10.01417

with(dF,
     sort(x))

##  [1]  5.570600  8.359063  8.757519  9.389223 10.659016 10.779686
##  [7] 10.974858 11.151563 11.476649 13.023562

# -----------------------------------------------------------------------------
# Outras funções
# -----------------------------------------------------------------------------  
x = c(1.73, 1.43, 2.1, 4.3, 5.1)
x

## [1] 1.73 1.43 2.10 4.30 5.10

length(x)       # Número de elementos

## [1] 5

min(x)

## [1] 1.43

max(x)

## [1] 5.1

sort(x)         # Ordena os valores dentro de um vetor

## [1] 1.43 1.73 2.10 4.30 5.10

sort(x,
     decreasing = TRUE)

## [1] 5.10 4.30 2.10 1.73 1.43

median(x)       # Mediana

## [1] 2.1

mean(x)         # Média

## [1] 2.932

var(x)          # Variância

## [1] 2.74117

sd(x)           # Desvio padrão (standard deviation)

## [1] 1.655648

sqrt(var(x))    # raiz quadrada

## [1] 1.655648

sum(x)          # Somatório

## [1] 14.66

round(x)        # Arrendondar

## [1] 2 1 2 4 5

round(x,
      digits = 1)

## [1] 1.7 1.4 2.1 4.3 5.1

round(x,
      1)

## [1] 1.7 1.4 2.1 4.3 5.1

# -----------------------------------------------------------------------------
# Gráficos
# -----------------------------------------------------------------------------
# Será utilizado a library default do R, a 'Graphics'. Existem outras
# bibliotecas, como: lattice, ggplot2, etc. 
x = seq(1, 10)
x

##  [1]  1  2  3  4  5  6  7  8  9 10

y = 3 + x
y

##  [1]  4  5  6  7  8  9 10 11 12 13

plot(y ~ x)# ou

plot(x, y)

# Fazendo um gráfico um pouquinho mais elaborado!
plot(y ~ x,
     main = 'Exemplo 1',
     xlab = 'Variável x',
     ylab = 'Variável y',
     col = 'red',
     type = 'p',
     sub = 'VASCÃO')               

# Listando todas as cores dispníveis para uso em gráficos.
colors()  # Descobrir as cores disponíveis

##   [1] "white"                "aliceblue"           
##   [3] "antiquewhite"         "antiquewhite1"       
##   [5] "antiquewhite2"        "antiquewhite3"       
##   [7] "antiquewhite4"        "aquamarine"          
##   [9] "aquamarine1"          "aquamarine2"         
##  [11] "aquamarine3"          "aquamarine4"         
##  [13] "azure"                "azure1"              
##  [15] "azure2"               "azure3"              
##  [17] "azure4"               "beige"               
##  [19] "bisque"               "bisque1"             
##  [21] "bisque2"              "bisque3"             
##  [23] "bisque4"              "black"               
##  [25] "blanchedalmond"       "blue"                
##  [27] "blue1"                "blue2"               
##  [29] "blue3"                "blue4"               
##  [31] "blueviolet"           "brown"               
##  [33] "brown1"               "brown2"              
##  [35] "brown3"               "brown4"              
##  [37] "burlywood"            "burlywood1"          
##  [39] "burlywood2"           "burlywood3"          
##  [41] "burlywood4"           "cadetblue"           
##  [43] "cadetblue1"           "cadetblue2"          
##  [45] "cadetblue3"           "cadetblue4"          
##  [47] "chartreuse"           "chartreuse1"         
##  [49] "chartreuse2"          "chartreuse3"         
##  [51] "chartreuse4"          "chocolate"           
##  [53] "chocolate1"           "chocolate2"          
##  [55] "chocolate3"           "chocolate4"          
##  [57] "coral"                "coral1"              
##  [59] "coral2"               "coral3"              
##  [61] "coral4"               "cornflowerblue"      
##  [63] "cornsilk"             "cornsilk1"           
##  [65] "cornsilk2"            "cornsilk3"           
##  [67] "cornsilk4"            "cyan"                
##  [69] "cyan1"                "cyan2"               
##  [71] "cyan3"                "cyan4"               
##  [73] "darkblue"             "darkcyan"            
##  [75] "darkgoldenrod"        "darkgoldenrod1"      
##  [77] "darkgoldenrod2"       "darkgoldenrod3"      
##  [79] "darkgoldenrod4"       "darkgray"            
##  [81] "darkgreen"            "darkgrey"            
##  [83] "darkkhaki"            "darkmagenta"         
##  [85] "darkolivegreen"       "darkolivegreen1"     
##  [87] "darkolivegreen2"      "darkolivegreen3"     
##  [89] "darkolivegreen4"      "darkorange"          
##  [91] "darkorange1"          "darkorange2"         
##  [93] "darkorange3"          "darkorange4"         
##  [95] "darkorchid"           "darkorchid1"         
##  [97] "darkorchid2"          "darkorchid3"         
##  [99] "darkorchid4"          "darkred"             
## [101] "darksalmon"           "darkseagreen"        
## [103] "darkseagreen1"        "darkseagreen2"       
## [105] "darkseagreen3"        "darkseagreen4"       
## [107] "darkslateblue"        "darkslategray"       
## [109] "darkslategray1"       "darkslategray2"      
## [111] "darkslategray3"       "darkslategray4"      
## [113] "darkslategrey"        "darkturquoise"       
## [115] "darkviolet"           "deeppink"            
## [117] "deeppink1"            "deeppink2"           
## [119] "deeppink3"            "deeppink4"           
## [121] "deepskyblue"          "deepskyblue1"        
## [123] "deepskyblue2"         "deepskyblue3"        
## [125] "deepskyblue4"         "dimgray"             
## [127] "dimgrey"              "dodgerblue"          
## [129] "dodgerblue1"          "dodgerblue2"         
## [131] "dodgerblue3"          "dodgerblue4"         
## [133] "firebrick"            "firebrick1"          
## [135] "firebrick2"           "firebrick3"          
## [137] "firebrick4"           "floralwhite"         
## [139] "forestgreen"          "gainsboro"           
## [141] "ghostwhite"           "gold"                
## [143] "gold1"                "gold2"               
## [145] "gold3"                "gold4"               
## [147] "goldenrod"            "goldenrod1"          
## [149] "goldenrod2"           "goldenrod3"          
## [151] "goldenrod4"           "gray"                
## [153] "gray0"                "gray1"               
## [155] "gray2"                "gray3"               
## [157] "gray4"                "gray5"               
## [159] "gray6"                "gray7"               
## [161] "gray8"                "gray9"               
## [163] "gray10"               "gray11"              
## [165] "gray12"               "gray13"              
## [167] "gray14"               "gray15"              
## [169] "gray16"               "gray17"              
## [171] "gray18"               "gray19"              
## [173] "gray20"               "gray21"              
## [175] "gray22"               "gray23"              
## [177] "gray24"               "gray25"              
## [179] "gray26"               "gray27"              
## [181] "gray28"               "gray29"              
## [183] "gray30"               "gray31"              
## [185] "gray32"               "gray33"              
## [187] "gray34"               "gray35"              
## [189] "gray36"               "gray37"              
## [191] "gray38"               "gray39"              
## [193] "gray40"               "gray41"              
## [195] "gray42"               "gray43"              
## [197] "gray44"               "gray45"              
## [199] "gray46"               "gray47"              
## [201] "gray48"               "gray49"              
## [203] "gray50"               "gray51"              
## [205] "gray52"               "gray53"              
## [207] "gray54"               "gray55"              
## [209] "gray56"               "gray57"              
## [211] "gray58"               "gray59"              
## [213] "gray60"               "gray61"              
## [215] "gray62"               "gray63"              
## [217] "gray64"               "gray65"              
## [219] "gray66"               "gray67"              
## [221] "gray68"               "gray69"              
## [223] "gray70"               "gray71"              
## [225] "gray72"               "gray73"              
## [227] "gray74"               "gray75"              
## [229] "gray76"               "gray77"              
## [231] "gray78"               "gray79"              
## [233] "gray80"               "gray81"              
## [235] "gray82"               "gray83"              
## [237] "gray84"               "gray85"              
## [239] "gray86"               "gray87"              
## [241] "gray88"               "gray89"              
## [243] "gray90"               "gray91"              
## [245] "gray92"               "gray93"              
## [247] "gray94"               "gray95"              
## [249] "gray96"               "gray97"              
## [251] "gray98"               "gray99"              
## [253] "gray100"              "green"               
## [255] "green1"               "green2"              
## [257] "green3"               "green4"              
## [259] "greenyellow"          "grey"                
## [261] "grey0"                "grey1"               
## [263] "grey2"                "grey3"               
## [265] "grey4"                "grey5"               
## [267] "grey6"                "grey7"               
## [269] "grey8"                "grey9"               
## [271] "grey10"               "grey11"              
## [273] "grey12"               "grey13"              
## [275] "grey14"               "grey15"              
## [277] "grey16"               "grey17"              
## [279] "grey18"               "grey19"              
## [281] "grey20"               "grey21"              
## [283] "grey22"               "grey23"              
## [285] "grey24"               "grey25"              
## [287] "grey26"               "grey27"              
## [289] "grey28"               "grey29"              
## [291] "grey30"               "grey31"              
## [293] "grey32"               "grey33"              
## [295] "grey34"               "grey35"              
## [297] "grey36"               "grey37"              
## [299] "grey38"               "grey39"              
## [301] "grey40"               "grey41"              
## [303] "grey42"               "grey43"              
## [305] "grey44"               "grey45"              
## [307] "grey46"               "grey47"              
## [309] "grey48"               "grey49"              
## [311] "grey50"               "grey51"              
## [313] "grey52"               "grey53"              
## [315] "grey54"               "grey55"              
## [317] "grey56"               "grey57"              
## [319] "grey58"               "grey59"              
## [321] "grey60"               "grey61"              
## [323] "grey62"               "grey63"              
## [325] "grey64"               "grey65"              
## [327] "grey66"               "grey67"              
## [329] "grey68"               "grey69"              
## [331] "grey70"               "grey71"              
## [333] "grey72"               "grey73"              
## [335] "grey74"               "grey75"              
## [337] "grey76"               "grey77"              
## [339] "grey78"               "grey79"              
## [341] "grey80"               "grey81"              
## [343] "grey82"               "grey83"              
## [345] "grey84"               "grey85"              
## [347] "grey86"               "grey87"              
## [349] "grey88"               "grey89"              
## [351] "grey90"               "grey91"              
## [353] "grey92"               "grey93"              
## [355] "grey94"               "grey95"              
## [357] "grey96"               "grey97"              
## [359] "grey98"               "grey99"              
## [361] "grey100"              "honeydew"            
## [363] "honeydew1"            "honeydew2"           
## [365] "honeydew3"            "honeydew4"           
## [367] "hotpink"              "hotpink1"            
## [369] "hotpink2"             "hotpink3"            
## [371] "hotpink4"             "indianred"           
## [373] "indianred1"           "indianred2"          
## [375] "indianred3"           "indianred4"          
## [377] "ivory"                "ivory1"              
## [379] "ivory2"               "ivory3"              
## [381] "ivory4"               "khaki"               
## [383] "khaki1"               "khaki2"              
## [385] "khaki3"               "khaki4"              
## [387] "lavender"             "lavenderblush"       
## [389] "lavenderblush1"       "lavenderblush2"      
## [391] "lavenderblush3"       "lavenderblush4"      
## [393] "lawngreen"            "lemonchiffon"        
## [395] "lemonchiffon1"        "lemonchiffon2"       
## [397] "lemonchiffon3"        "lemonchiffon4"       
## [399] "lightblue"            "lightblue1"          
## [401] "lightblue2"           "lightblue3"          
## [403] "lightblue4"           "lightcoral"          
## [405] "lightcyan"            "lightcyan1"          
## [407] "lightcyan2"           "lightcyan3"          
## [409] "lightcyan4"           "lightgoldenrod"      
## [411] "lightgoldenrod1"      "lightgoldenrod2"     
## [413] "lightgoldenrod3"      "lightgoldenrod4"     
## [415] "lightgoldenrodyellow" "lightgray"           
## [417] "lightgreen"           "lightgrey"           
## [419] "lightpink"            "lightpink1"          
## [421] "lightpink2"           "lightpink3"          
## [423] "lightpink4"           "lightsalmon"         
## [425] "lightsalmon1"         "lightsalmon2"        
## [427] "lightsalmon3"         "lightsalmon4"        
## [429] "lightseagreen"        "lightskyblue"        
## [431] "lightskyblue1"        "lightskyblue2"       
## [433] "lightskyblue3"        "lightskyblue4"       
## [435] "lightslateblue"       "lightslategray"      
## [437] "lightslategrey"       "lightsteelblue"      
## [439] "lightsteelblue1"      "lightsteelblue2"     
## [441] "lightsteelblue3"      "lightsteelblue4"     
## [443] "lightyellow"          "lightyellow1"        
## [445] "lightyellow2"         "lightyellow3"        
## [447] "lightyellow4"         "limegreen"           
## [449] "linen"                "magenta"             
## [451] "magenta1"             "magenta2"            
## [453] "magenta3"             "magenta4"            
## [455] "maroon"               "maroon1"             
## [457] "maroon2"              "maroon3"             
## [459] "maroon4"              "mediumaquamarine"    
## [461] "mediumblue"           "mediumorchid"        
## [463] "mediumorchid1"        "mediumorchid2"       
## [465] "mediumorchid3"        "mediumorchid4"       
## [467] "mediumpurple"         "mediumpurple1"       
## [469] "mediumpurple2"        "mediumpurple3"       
## [471] "mediumpurple4"        "mediumseagreen"      
## [473] "mediumslateblue"      "mediumspringgreen"   
## [475] "mediumturquoise"      "mediumvioletred"     
## [477] "midnightblue"         "mintcream"           
## [479] "mistyrose"            "mistyrose1"          
## [481] "mistyrose2"           "mistyrose3"          
## [483] "mistyrose4"           "moccasin"            
## [485] "navajowhite"          "navajowhite1"        
## [487] "navajowhite2"         "navajowhite3"        
## [489] "navajowhite4"         "navy"                
## [491] "navyblue"             "oldlace"             
## [493] "olivedrab"            "olivedrab1"          
## [495] "olivedrab2"           "olivedrab3"          
## [497] "olivedrab4"           "orange"              
## [499] "orange1"              "orange2"             
## [501] "orange3"              "orange4"             
## [503] "orangered"            "orangered1"          
## [505] "orangered2"           "orangered3"          
## [507] "orangered4"           "orchid"              
## [509] "orchid1"              "orchid2"             
## [511] "orchid3"              "orchid4"             
## [513] "palegoldenrod"        "palegreen"           
## [515] "palegreen1"           "palegreen2"          
## [517] "palegreen3"           "palegreen4"          
## [519] "paleturquoise"        "paleturquoise1"      
## [521] "paleturquoise2"       "paleturquoise3"      
## [523] "paleturquoise4"       "palevioletred"       
## [525] "palevioletred1"       "palevioletred2"      
## [527] "palevioletred3"       "palevioletred4"      
## [529] "papayawhip"           "peachpuff"           
## [531] "peachpuff1"           "peachpuff2"          
## [533] "peachpuff3"           "peachpuff4"          
## [535] "peru"                 "pink"                
## [537] "pink1"                "pink2"               
## [539] "pink3"                "pink4"               
## [541] "plum"                 "plum1"               
## [543] "plum2"                "plum3"               
## [545] "plum4"                "powderblue"          
## [547] "purple"               "purple1"             
## [549] "purple2"              "purple3"             
## [551] "purple4"              "red"                 
## [553] "red1"                 "red2"                
## [555] "red3"                 "red4"                
## [557] "rosybrown"            "rosybrown1"          
## [559] "rosybrown2"           "rosybrown3"          
## [561] "rosybrown4"           "royalblue"           
## [563] "royalblue1"           "royalblue2"          
## [565] "royalblue3"           "royalblue4"          
## [567] "saddlebrown"          "salmon"              
## [569] "salmon1"              "salmon2"             
## [571] "salmon3"              "salmon4"             
## [573] "sandybrown"           "seagreen"            
## [575] "seagreen1"            "seagreen2"           
## [577] "seagreen3"            "seagreen4"           
## [579] "seashell"             "seashell1"           
## [581] "seashell2"            "seashell3"           
## [583] "seashell4"            "sienna"              
## [585] "sienna1"              "sienna2"             
## [587] "sienna3"              "sienna4"             
## [589] "skyblue"              "skyblue1"            
## [591] "skyblue2"             "skyblue3"            
## [593] "skyblue4"             "slateblue"           
## [595] "slateblue1"           "slateblue2"          
## [597] "slateblue3"           "slateblue4"          
## [599] "slategray"            "slategray1"          
## [601] "slategray2"           "slategray3"          
## [603] "slategray4"           "slategrey"           
## [605] "snow"                 "snow1"               
## [607] "snow2"                "snow3"               
## [609] "snow4"                "springgreen"         
## [611] "springgreen1"         "springgreen2"        
## [613] "springgreen3"         "springgreen4"        
## [615] "steelblue"            "steelblue1"          
## [617] "steelblue2"           "steelblue3"          
## [619] "steelblue4"           "tan"                 
## [621] "tan1"                 "tan2"                
## [623] "tan3"                 "tan4"                
## [625] "thistle"              "thistle1"            
## [627] "thistle2"             "thistle3"            
## [629] "thistle4"             "tomato"              
## [631] "tomato1"              "tomato2"             
## [633] "tomato3"              "tomato4"             
## [635] "turquoise"            "turquoise1"          
## [637] "turquoise2"           "turquoise3"          
## [639] "turquoise4"           "violet"              
## [641] "violetred"            "violetred1"          
## [643] "violetred2"           "violetred3"          
## [645] "violetred4"           "wheat"               
## [647] "wheat1"               "wheat2"              
## [649] "wheat3"               "wheat4"              
## [651] "whitesmoke"           "yellow"              
## [653] "yellow1"              "yellow2"             
## [655] "yellow3"              "yellow4"             
## [657] "yellowgreen"