Chapter 3 Standard graphical formatting in R
Introduction plot() function:
plot() function is generic function for plotting of R objects in basic graphs.
par(): the default settings (rows x columns) for plots.plot(): the main function.There are many other plot functions which are specific to some tasks such as
hist(),boxplot(), etc. Most of them take the same arguments as theplot()function.
Formula:
plot(x, y, type=“p”)
x and y: the coordinates of points to plot
type:“p” for points,
“l” for lines,
“b” for both,
“c” for the lines part alone of “b”,
“o” for both ‘overplotted’,
“h” for ‘histogram’ like (or ‘high-density’) vertical lines,
“s” for stair steps,
“S” for other steps, see ‘Details’ below,
“n” for no plotting.
Example:
par(mfrow=c(3,3), mar=c(3,3,1,0)+.5, mgp=c(1.6,.6,0)) # set up the graphics
x<-1:5; y=x*x
plot(x, y, type="p",col="blue")
plot(x, y, type="l",col="bisque")
plot(x,y, type="b",col="green")
plot(x, y, type="c",col="red")
plot(x, y, type="o",col="pink")
plot(x,y, type="h",col="orange")
plot(x, y, type="s",col="purple")
plot(x, y, type="S",col="black")
plot(x,y, type="h",col="blue")
For more color type used the sintaks color()
More info about plot() go to RDocumentation here
Titles:
main="test": main titlessub="text": subtitlexlab="test": the name of the x axisylab="test": the name of the y axis.
====Main title and axis labels====
x<-1:5; y=x*x
plot(x, y, type="p",col="blue",main="Exponential",sub="Example",ylab="Y Axis",xlab="X Axis")
====Title colors====
x<-1:5; y=x*x
plot(x, y, type="p",col="#B7F200",main="Exponential",sub="Example",ylab="Y Axis",xlab="X Axis",
col.main="red", col.lab="blue", col.sub="green")
====The font style====
The possible values for the font style are :
1: normal text 2: bold 3: italic 4: bold and italic 5 : Symbol font
x<-1:5; y=x*x
plot(x, y, type="p",col="blue",main="Exponential",sub="Example",ylab="Y Axis",xlab="X Axis",
font.main=1, font.lab=2, font.sub=3
)
====The font size====
x<-1:5; y=x*x
plot(x, y, type="p",col="blue",main="Exponential",sub="Example",ylab="Y Axis",xlab="X Axis",
cex.main=4, cex.lab=1.5, cex.sub=0.8
)
====Use the title() function====
x<-1:5; y=x*x
plot(x, y, type="p")
title(main = "Main title", sub = "Sub-title",
xlab = "X", ylab = "Y",
cex.main = 2, font.main= 4, col.main= "red",
cex.sub = 0.75, font.sub = 2, col.sub = "green",
col.lab ="darkblue"
)
====Customize the titles using par() function====
par(
# Change the colors
col.main="red", col.lab="blue", col.sub="black",
# Titles in italic and bold
font.main=4, font.lab=4, font.sub=4,
# Change font size
cex.main=2, cex.lab=1.7, cex.sub=1.2
)
plot(x, y, type="p",
main="TMain title",
xlab="X axis",
ylab="Y axis",
sub="Sub title"
)
Legend:
legend(): the position can be “bottomleft”, “bottomright”, “topleft”, “topright” or exact coordinates.
====R legend function====
Formula:
legend(x, y=NULL, legend, fill, col, bg)
Example:
# Generate example data
x<-1:5; y1=x*x; y2=3*y1
plot(x, y1, type="b", pch=19, col="#FFD900", xlab="x", ylab="y")
# Add a line
lines(x, y2, pch=18, col="#8C6DD7", type="b", lty=2)
# Add a legend
legend(1, 20, legend=c("Line 1", "Line 2"),
col=c("#FFD900", "#8C6DD7"), lty=1:2, cex=0.8)
Create R function to avoid repeating graphs code:
# Generate example data
make_plot<-function(){
x<-1:5; y1=x*x; y2=3*y1
plot(x, y1, type="b", pch=19, col="red", xlab="x", ylab="y")
# Add a line
lines(x, y2, pch=18, col="blue", type="b", lty=2)
# Add a legend
legend(1, 20, legend=c("Line 1", "Line 2"),
col=c("red", "blue"), lty=1:2, cex=0.8)
}make_plot()
====Title, text font and background color of the legend box====
- title: The title of the legend
- text.font: an integer specifying the font style of the legend text; possible values are :
- 1: normal
- 2: bold
- 3: italic
- 4: bold and italic
- bg: background color of the legend box
make_plot()
# Add a legend to the plot
legend(1,20, legend=c("Line 1", "Line 2"),
col=c("red", "blue"), lty=1:2, cex=0.8,
title="Line types", text.font=4, bg="lightblue")
====Border of the legend box====
box.lty: modify the line type
box.lwd: modify the width
box.col: modify the color
par(mfrow=c(2,1), mar=c(3,3,1,0)+.5, mgp=c(1.6,.6,0)) # set up the graphics
# Remove legend border using box.lty = 0
make_plot()
legend(1,20, legend=c("Line 1", "Line 2"),
col=c("red", "blue"), lty=1:2, cex=0.8,
box.lty=0)
# Change the border
make_plot()
legend(1,20, legend=c("Line 1", "Line 2"),
col=c("red", "blue"), lty=1:2, cex=0.8,
box.lty=2, box.lwd=2, box.col="green")
====The legend position by keywords====
Using the following keywords : “bottomright”, “bottom”, “bottomleft”, “left”, “topleft”, “top”, “topright”, “right” and “center”.
par(mfrow=c(2,1), mar=c(3,3,1,0)+.5, mgp=c(1.6,.6,0)) # set up the graphics
# Remove legend border using box.lty = 0
make_plot()
legend("center", legend=c("Line 1", "Line 2"),
col=c("red", "blue"),box.lty=0)
make_plot()
legend("topright", legend=c("Line 1", "Line 2"),
col=c("red", "blue"),
box.lty=0)
Text:
text() and mtext() R functions can be used To add a text to a plot.
====Texts within the graph====
Formula:
text(x, y, labels)
Example:
d<-head(mtcars)
plot(d[,'wt'], d[,'mpg'],
main="Milage vs. Car Weight\n~~~~~~~~~~~~~~~~~~~",
xlab="Weight", ylab="Miles/(US) gallon",
pch=19, col="darkgreen")
text(d[,'wt'], d[,'mpg'], row.names(d),
cex=0.85, pos=2,col="red")
====Text in the margins of the graph====
- text : the text to be written
- side : an integer specifying the side of the plot; Possible values are :
- 1: bottom
- 2: left
- 3: top
- 4: right
plot(1:7, 1:7,
main="mtext(...) examples",col="blue")
mtext("Magic function", side=4)
====Mathematical annotation within the graph====
Example:
plot(1:7, 1:7,
main="text(...) examples",col="black")
text(2, 4, expression(hat(beta) == (X^t * X)^{-1} * X^t * y))
text(2, 6, expression(bar(x) == sum(frac(x[i], n), i==1, n)))
Types of Plot:
An option for plot types can be:
type: * “p” for points,
* "l" for lines,
* "b" for both,
* "c" for the lines part alone of "b",
* "o" for both 'overplotted',
* "h" for 'histogram' like (or 'high-density') vertical lines,
* "s" for stair steps,
* "S" for other steps, see 'Details' below,
* "n" for no plotting.x <- rnorm(100)
par(mfrow = c(2,2))
plot(x, type = "p", main = "points", ylab = "", xlab = "",col="red")
plot(x, type = "o", main = "overplotted", ylab = "", xlab = "",col="green")
plot(x, type = "h", main = "histogram", ylab = "", xlab = "",col="blue")
plot(x, type = "S", main = "steps", ylab = "", xlab = "",col="orange")
Axis:
====Add an axis to a plot====
Formula:
axis(side, at=NULL, labels=TRUE)
Side :
1: below
2: left
3: above
4: right
at: The position
labels: Texts for tick-mark labels.
Example :
par(mfrow=c(3,1), mar=c(3,3,1,0)+.5, mgp=c(1.6,.6,0)) # set up the graphics
x<-1:3; y=x*x
# Example 1
plot(x, y, axes = FALSE)
axis(side=1, at = 1:3, labels=LETTERS[1:3])
axis(2)
# Example 2
plot(x, y, axes = FALSE)
axis(side=1, at=1:3, labels=LETTERS[1:3])
axis(2)
box() #- To make it look like "usual" plot
#Example3:
plot(x, y, pch=18, col="red", type="b",
frame=FALSE, xaxt="n") # Remove x axis
axis(1, 1:4, LETTERS[1:4], col.axis="blue")
axis(3, col = "darkgreen", lty = 2, lwd = 0.5)
axis(4, col = "violet", col.axis = "dark violet", lwd = 2)
====Axis scale====
xlim: the limit of x axis; format : xlim = c(min, max)
ylim: the limit of y axis; format: ylim = c(min, max)
Transformation to log scale:
log = “x”
log = “y”
log = “xy”*
Example:
par(mfrow=c(3,1), mar=c(3,3,1,0)+.5, mgp=c(1.6,.6,0)) # set up the graphics
x<-1:20; y=x*x
# Simple graph
plot(x, y,col="blue")
# Enlarge the scale
plot(x, y, xlim=c(1,15), ylim=c(1,150),col="blue")
# Log scale
plot(x, y, log="y",col="blue")
====Axes fonts====
Remove them with axes=FALSE:
par(mfrow=c(2,1), mar=c(3,3,1,0)+.5, mgp=c(1.6,.6,0)) # set up the graphics
x1<-1:10
x2<-11:20
plot(x1,x2,axes=FALSE)
plot(x1,x2,axes=FALSE)
axis(1,col="red",col.axis="blue",font.axis=3)
axis(2,col="red",col.axis="blue",font.axis=2,las=2)
====Axes positions====
Use las function to specified the style of axis labels:
0 : always parallel to the axis [default]
1 : always horizontal
2 : always perpendicular to the axis
3 : always vertical
x1 <- rnorm(150)
par(mfrow = c(2,2))
plot(x1, las = 0, main = "las = 0", sub = "always parallel to the axis", xlab = "", ylab = "",col="blue")
plot(x1, las = 1, main = "las = 1", sub = "always horizontal", xlab = "", ylab = "",col="blue")
plot(x1, las = 2, main = "las = 2", sub = "always perpendicular to the axis", xlab = "", ylab = "",col="blue")
plot(x1, las = 3, main = "las = 3", sub = "always vertical", xlab = "", ylab = "",col="blue")
Margins par():
Formula:
par(mfrow=c(2,1), mar=c(3,3,1,0)+.5, mgp=c(1.6,.6,0)) # set up the graphics
See ?par to learn more about the topic.
Colors:
Use by name (e.g col = “red”) or as a hexadecimal RGB triplet (such as col = “#FFCC00”).
====Default color in R====
colors() # list the r colors## [1] "white" "aliceblue" "antiquewhite"
## [4] "antiquewhite1" "antiquewhite2" "antiquewhite3"
## [7] "antiquewhite4" "aquamarine" "aquamarine1"
## [10] "aquamarine2" "aquamarine3" "aquamarine4"
## [13] "azure" "azure1" "azure2"
## [16] "azure3" "azure4" "beige"
## [19] "bisque" "bisque1" "bisque2"
## [22] "bisque3" "bisque4" "black"
## [25] "blanchedalmond" "blue" "blue1"
## [28] "blue2" "blue3" "blue4"
## [31] "blueviolet" "brown" "brown1"
## [34] "brown2" "brown3" "brown4"
## [37] "burlywood" "burlywood1" "burlywood2"
## [40] "burlywood3" "burlywood4" "cadetblue"
## [43] "cadetblue1" "cadetblue2" "cadetblue3"
## [46] "cadetblue4" "chartreuse" "chartreuse1"
## [49] "chartreuse2" "chartreuse3" "chartreuse4"
## [52] "chocolate" "chocolate1" "chocolate2"
## [55] "chocolate3" "chocolate4" "coral"
## [58] "coral1" "coral2" "coral3"
## [61] "coral4" "cornflowerblue" "cornsilk"
## [64] "cornsilk1" "cornsilk2" "cornsilk3"
## [67] "cornsilk4" "cyan" "cyan1"
## [70] "cyan2" "cyan3" "cyan4"
## [73] "darkblue" "darkcyan" "darkgoldenrod"
## [76] "darkgoldenrod1" "darkgoldenrod2" "darkgoldenrod3"
## [79] "darkgoldenrod4" "darkgray" "darkgreen"
## [82] "darkgrey" "darkkhaki" "darkmagenta"
## [85] "darkolivegreen" "darkolivegreen1" "darkolivegreen2"
## [88] "darkolivegreen3" "darkolivegreen4" "darkorange"
## [91] "darkorange1" "darkorange2" "darkorange3"
## [94] "darkorange4" "darkorchid" "darkorchid1"
## [97] "darkorchid2" "darkorchid3" "darkorchid4"
## [100] "darkred" "darksalmon" "darkseagreen"
## [103] "darkseagreen1" "darkseagreen2" "darkseagreen3"
## [106] "darkseagreen4" "darkslateblue" "darkslategray"
## [109] "darkslategray1" "darkslategray2" "darkslategray3"
## [112] "darkslategray4" "darkslategrey" "darkturquoise"
## [115] "darkviolet" "deeppink" "deeppink1"
## [118] "deeppink2" "deeppink3" "deeppink4"
## [121] "deepskyblue" "deepskyblue1" "deepskyblue2"
## [124] "deepskyblue3" "deepskyblue4" "dimgray"
## [127] "dimgrey" "dodgerblue" "dodgerblue1"
## [130] "dodgerblue2" "dodgerblue3" "dodgerblue4"
## [133] "firebrick" "firebrick1" "firebrick2"
## [136] "firebrick3" "firebrick4" "floralwhite"
## [139] "forestgreen" "gainsboro" "ghostwhite"
## [142] "gold" "gold1" "gold2"
## [145] "gold3" "gold4" "goldenrod"
## [148] "goldenrod1" "goldenrod2" "goldenrod3"
## [151] "goldenrod4" "gray" "gray0"
## [154] "gray1" "gray2" "gray3"
## [157] "gray4" "gray5" "gray6"
## [160] "gray7" "gray8" "gray9"
## [163] "gray10" "gray11" "gray12"
## [166] "gray13" "gray14" "gray15"
## [169] "gray16" "gray17" "gray18"
## [172] "gray19" "gray20" "gray21"
## [175] "gray22" "gray23" "gray24"
## [178] "gray25" "gray26" "gray27"
## [181] "gray28" "gray29" "gray30"
## [184] "gray31" "gray32" "gray33"
## [187] "gray34" "gray35" "gray36"
## [190] "gray37" "gray38" "gray39"
## [193] "gray40" "gray41" "gray42"
## [196] "gray43" "gray44" "gray45"
## [199] "gray46" "gray47" "gray48"
## [202] "gray49" "gray50" "gray51"
## [205] "gray52" "gray53" "gray54"
## [208] "gray55" "gray56" "gray57"
## [211] "gray58" "gray59" "gray60"
## [214] "gray61" "gray62" "gray63"
## [217] "gray64" "gray65" "gray66"
## [220] "gray67" "gray68" "gray69"
## [223] "gray70" "gray71" "gray72"
## [226] "gray73" "gray74" "gray75"
## [229] "gray76" "gray77" "gray78"
## [232] "gray79" "gray80" "gray81"
## [235] "gray82" "gray83" "gray84"
## [238] "gray85" "gray86" "gray87"
## [241] "gray88" "gray89" "gray90"
## [244] "gray91" "gray92" "gray93"
## [247] "gray94" "gray95" "gray96"
## [250] "gray97" "gray98" "gray99"
## [253] "gray100" "green" "green1"
## [256] "green2" "green3" "green4"
## [259] "greenyellow" "grey" "grey0"
## [262] "grey1" "grey2" "grey3"
## [265] "grey4" "grey5" "grey6"
## [268] "grey7" "grey8" "grey9"
## [271] "grey10" "grey11" "grey12"
## [274] "grey13" "grey14" "grey15"
## [277] "grey16" "grey17" "grey18"
## [280] "grey19" "grey20" "grey21"
## [283] "grey22" "grey23" "grey24"
## [286] "grey25" "grey26" "grey27"
## [289] "grey28" "grey29" "grey30"
## [292] "grey31" "grey32" "grey33"
## [295] "grey34" "grey35" "grey36"
## [298] "grey37" "grey38" "grey39"
## [301] "grey40" "grey41" "grey42"
## [304] "grey43" "grey44" "grey45"
## [307] "grey46" "grey47" "grey48"
## [310] "grey49" "grey50" "grey51"
## [313] "grey52" "grey53" "grey54"
## [316] "grey55" "grey56" "grey57"
## [319] "grey58" "grey59" "grey60"
## [322] "grey61" "grey62" "grey63"
## [325] "grey64" "grey65" "grey66"
## [328] "grey67" "grey68" "grey69"
## [331] "grey70" "grey71" "grey72"
## [334] "grey73" "grey74" "grey75"
## [337] "grey76" "grey77" "grey78"
## [340] "grey79" "grey80" "grey81"
## [343] "grey82" "grey83" "grey84"
## [346] "grey85" "grey86" "grey87"
## [349] "grey88" "grey89" "grey90"
## [352] "grey91" "grey92" "grey93"
## [355] "grey94" "grey95" "grey96"
## [358] "grey97" "grey98" "grey99"
## [361] "grey100" "honeydew" "honeydew1"
## [364] "honeydew2" "honeydew3" "honeydew4"
## [367] "hotpink" "hotpink1" "hotpink2"
## [370] "hotpink3" "hotpink4" "indianred"
## [373] "indianred1" "indianred2" "indianred3"
## [376] "indianred4" "ivory" "ivory1"
## [379] "ivory2" "ivory3" "ivory4"
## [382] "khaki" "khaki1" "khaki2"
## [385] "khaki3" "khaki4" "lavender"
## [388] "lavenderblush" "lavenderblush1" "lavenderblush2"
## [391] "lavenderblush3" "lavenderblush4" "lawngreen"
## [394] "lemonchiffon" "lemonchiffon1" "lemonchiffon2"
## [397] "lemonchiffon3" "lemonchiffon4" "lightblue"
## [400] "lightblue1" "lightblue2" "lightblue3"
## [403] "lightblue4" "lightcoral" "lightcyan"
## [406] "lightcyan1" "lightcyan2" "lightcyan3"
## [409] "lightcyan4" "lightgoldenrod" "lightgoldenrod1"
## [412] "lightgoldenrod2" "lightgoldenrod3" "lightgoldenrod4"
## [415] "lightgoldenrodyellow" "lightgray" "lightgreen"
## [418] "lightgrey" "lightpink" "lightpink1"
## [421] "lightpink2" "lightpink3" "lightpink4"
## [424] "lightsalmon" "lightsalmon1" "lightsalmon2"
## [427] "lightsalmon3" "lightsalmon4" "lightseagreen"
## [430] "lightskyblue" "lightskyblue1" "lightskyblue2"
## [433] "lightskyblue3" "lightskyblue4" "lightslateblue"
## [436] "lightslategray" "lightslategrey" "lightsteelblue"
## [439] "lightsteelblue1" "lightsteelblue2" "lightsteelblue3"
## [442] "lightsteelblue4" "lightyellow" "lightyellow1"
## [445] "lightyellow2" "lightyellow3" "lightyellow4"
## [448] "limegreen" "linen" "magenta"
## [451] "magenta1" "magenta2" "magenta3"
## [454] "magenta4" "maroon" "maroon1"
## [457] "maroon2" "maroon3" "maroon4"
## [460] "mediumaquamarine" "mediumblue" "mediumorchid"
## [463] "mediumorchid1" "mediumorchid2" "mediumorchid3"
## [466] "mediumorchid4" "mediumpurple" "mediumpurple1"
## [469] "mediumpurple2" "mediumpurple3" "mediumpurple4"
## [472] "mediumseagreen" "mediumslateblue" "mediumspringgreen"
## [475] "mediumturquoise" "mediumvioletred" "midnightblue"
## [478] "mintcream" "mistyrose" "mistyrose1"
## [481] "mistyrose2" "mistyrose3" "mistyrose4"
## [484] "moccasin" "navajowhite" "navajowhite1"
## [487] "navajowhite2" "navajowhite3" "navajowhite4"
## [490] "navy" "navyblue" "oldlace"
## [493] "olivedrab" "olivedrab1" "olivedrab2"
## [496] "olivedrab3" "olivedrab4" "orange"
## [499] "orange1" "orange2" "orange3"
## [502] "orange4" "orangered" "orangered1"
## [505] "orangered2" "orangered3" "orangered4"
## [508] "orchid" "orchid1" "orchid2"
## [511] "orchid3" "orchid4" "palegoldenrod"
## [514] "palegreen" "palegreen1" "palegreen2"
## [517] "palegreen3" "palegreen4" "paleturquoise"
## [520] "paleturquoise1" "paleturquoise2" "paleturquoise3"
## [523] "paleturquoise4" "palevioletred" "palevioletred1"
## [526] "palevioletred2" "palevioletred3" "palevioletred4"
## [529] "papayawhip" "peachpuff" "peachpuff1"
## [532] "peachpuff2" "peachpuff3" "peachpuff4"
## [535] "peru" "pink" "pink1"
## [538] "pink2" "pink3" "pink4"
## [541] "plum" "plum1" "plum2"
## [544] "plum3" "plum4" "powderblue"
## [547] "purple" "purple1" "purple2"
## [550] "purple3" "purple4" "red"
## [553] "red1" "red2" "red3"
## [556] "red4" "rosybrown" "rosybrown1"
## [559] "rosybrown2" "rosybrown3" "rosybrown4"
## [562] "royalblue" "royalblue1" "royalblue2"
## [565] "royalblue3" "royalblue4" "saddlebrown"
## [568] "salmon" "salmon1" "salmon2"
## [571] "salmon3" "salmon4" "sandybrown"
## [574] "seagreen" "seagreen1" "seagreen2"
## [577] "seagreen3" "seagreen4" "seashell"
## [580] "seashell1" "seashell2" "seashell3"
## [583] "seashell4" "sienna" "sienna1"
## [586] "sienna2" "sienna3" "sienna4"
## [589] "skyblue" "skyblue1" "skyblue2"
## [592] "skyblue3" "skyblue4" "slateblue"
## [595] "slateblue1" "slateblue2" "slateblue3"
## [598] "slateblue4" "slategray" "slategray1"
## [601] "slategray2" "slategray3" "slategray4"
## [604] "slategrey" "snow" "snow1"
## [607] "snow2" "snow3" "snow4"
## [610] "springgreen" "springgreen1" "springgreen2"
## [613] "springgreen3" "springgreen4" "steelblue"
## [616] "steelblue1" "steelblue2" "steelblue3"
## [619] "steelblue4" "tan" "tan1"
## [622] "tan2" "tan3" "tan4"
## [625] "thistle" "thistle1" "thistle2"
## [628] "thistle3" "thistle4" "tomato"
## [631] "tomato1" "tomato2" "tomato3"
## [634] "tomato4" "turquoise" "turquoise1"
## [637] "turquoise2" "turquoise3" "turquoise4"
## [640] "violet" "violetred" "violetred1"
## [643] "violetred2" "violetred3" "violetred4"
## [646] "wheat" "wheat1" "wheat2"
## [649] "wheat3" "wheat4" "whitesmoke"
## [652] "yellow" "yellow1" "yellow2"
## [655] "yellow3" "yellow4" "yellowgreen"More info about color scheme extractor code in R:
Points:
Using pch="". It has values between 1 till 25 or a single character.
par(mfrow=c(4,2), mar=c(3,3,1,0)+.5, mgp=c(1.6,.6,0)) # set up the graphics
x1<-rnorm(10)
plot(x1, type = "p", pch = 0)
plot(x1, type = "p", pch = 10)
plot(x1, type = "p", pch = 25)
plot(x1, type = "p", pch = "a")
plot(x1, type = "p", pch = "*")
plot(x1[1:26], type = "p", pch = 0:25)
plot(x1[1:26], type = "p", pch = letters)
Lines:
====Line types in R : lty====
lty for changing the lines type and lwd to change line width. The argument is a string (“blank”, “solid”, “dashed”, “dotted”, “dotdash”, “longdash”, or “twodash”) or an integer (0=blank, 1=solid (default), 2=dashed, 3=dotted, 4=dotdash, 5=longdash, 6=twodash)
#Line types
#++++++++++++++++++++++++++++++++++++++++++++
generateRLineTypes<-function(){
oldPar<-par()
par(font=2, mar=c(0,0,0,0))
plot(1, pch="", ylim=c(0,6), xlim=c(0,0.7), axes=FALSE,xlab="", ylab="")
for(i in 0:6) lines(c(0.3,0.7), c(i,i), lty=i, lwd=3)
text(rep(0.1,6), 0:6, labels=c("0.'blank'", "1.'solid'", "2.'dashed'", "3.'dotted'",
"4.'dotdash'", "5.'longdash'", "6.'twodash'"))
par(mar=oldPar$mar,font=oldPar$font )
}
generateRLineTypes()
Example:
par(mfrow=c(3,3), mar=c(3,3,1,0)+.5, mgp=c(1.6,.6,0)) # set up the graphics
x1<-1:5
plot(x1, type = "l", lty = "blank")
plot(x1, type = "l", lty = "solid")
plot(x1, type = "l", lty = "dashed")
plot(x1, type = "l", lty = "dotted")
plot(x1, type = "l", lty = "dotdash")
plot(x1, type = "l", lty = "longdash")
plot(x1, type = "l", lty = "twodash")
====An additional lines() on a graph====
Example:
x1<-c(1,5,7,20)
x2<-1:10
plot(x1, type = "l", lty = "solid",col="blue")
lines(x2, type = "o", lty = "dashed", col = "red")
====Straight abline()====
abline() can be used to add vertical, horizontal or regression lines.
Formula:
abline(a=NULL, b=NULL, h=NULL, v=NULL, …)
Vertical line:
par(mfrow=c(1,3), mar=c(3,3,1,0)+.5, mgp=c(1.6,.6,0)) # set up the graphics
#Example-1: Add one line
plot(cars)
abline(v=10, col="red")
#Example-2: add 2 lines
# change line colors, sizes and types
plot(cars)
abline(v=c(5,15), col=c("blue", "blue"), lty=c(1,2), lwd=c(1, 3))
#Example-3:
set.seed(1234); mydata<-rnorm(100)
hist(mydata, col="lightblue")
abline(v = mean(mydata), col="red", lwd=3, lty=2)
Horizontal line:
plot(cars,col="red")
abline(h=80, col="green")
Regression line:
lm() function to fit linear model.
par(mgp=c(2,1,0), mar=c(3,3,1,1))
# Fit regression line
require(stats)
reg<-lm(dist ~ speed, data = cars)
coeff=coefficients(reg)
# equation of the line :
eq = paste0("y = ", round(coeff[2],1), "*x ", round(coeff[1],1))
# plot
plot(cars, main=eq,col="blue")
abline(reg, col="red")
Boxes:
bty specifies the box type.
par(mfrow=c(4,2), mar=c(3,3,1,0)+.5, mgp=c(1.6,.6,0)) # set up the graphics
x1<-rnorm(50)
plot(x1, bty = "o") # the default
plot(x1, bty = "n") # no box
plot(x1, bty = "l")
plot(x1, bty = "7")
plot(x1, bty = "u")
plot(x1, bty = "c")
plot(x1, bty = "]")
box(lty = '1375', col = 'red')
Grid:
grid() adds a grid to the current graph.
Example:
x1<-rnorm(100)
plot(x1, col="#FF8100")
grid()
Background:
Change the background color with par(bg=).
Example:
x1<-rnorm(50)
par(bg="whitesmoke")
plot(x1, bty ="o",col="red") # the default
Overlaying plots:
matplot()
Example:
N <- 200
x1 <- rnorm(N)
x2 <- rnorm(N) + x1 + 1
y <- 1 + x1 + x2 + rnorm(N)
mydat <- data.frame(y,x1,x2)
matplot(mydat[,2:3], pch = 1:2)
Multiple plots:
par()for display multiple figuresmfrow = c(3,2): 3 row x 2 columnmfcol = c(3,2): same with mfrow but another positions
Example-1:
par(mfrow = c(3,2))
plot(x1, type = "n")
plot(x1, type = "p")
plot(x1, type = "l")
plot(x1, type = "h")
plot(x1, type = "s")
plot(x1, type = "S")
Example-2:
par(mfcol = c(3,2))
plot(x1, type = "n")
plot(x1, type = "p")
plot(x1, type = "l")
plot(x1, type = "h")
plot(x1, type = "s")
plot(x1, type = "S")