Share the Gallery !

191_management_of_dates R proposes a special data type for dates. It is important to use it since it make the creation of charts lot easier. Let’s illustrate it. This example is inspired from this webpage that provides lot of explanations.

First we create data. With the str function you can check the type of each column. Dates are recognized as factor.


# Create data
set.seed(124)
date=paste(   "2015/03/" , sample(seq(1,31),6) , sep="")
value=sample(seq(1,100) , 6)
data=data.frame(date,value)

# Date and time are recognized as factor:
str(data)

# Create data

set.seed(124)

date=paste( "2015/03/" , sample(seq(1,31),6) , sep="")

value=sample(seq(1,100) , 6)

data=data.frame(date,value)

# Date and time are recognized as factor:

str(data)

191_management_of_dates_bad

We can plot it but the results we observe is quite disapointing.


# So ploting them works bad --> wrong order, date without value are not represented, 
plot(data$value~data$date)

# So ploting them works bad --> wrong order, date without value are not represented,

plot(data$value~data$date)

191_management_of_dates

If we switch to a date format and add a little bit of pimpimg, it becomes a better chart!


# Let's change the date to the "date" format:
data$date=as.Date(data$date)

# So we can sort the table:
data=data[order(data$date) , ]

# and replot --> R now understand how to plot it!
plot(data$value~data$date)

# Easy to make it better now:
plot(data$value~data$date , type="b" , lwd=3 , col=rgb(0.1,0.7,0.1,0.8) , ylab="value of ..." , xlab="date" , bty="l" , pch=20 , cex=4)
abline(h=seq(0,100,10) , col="grey", lwd=0.8)

# Let's change the date to the "date" format:

data$date=as.Date(data$date)

# So we can sort the table:

data=data[order(data$date) , ]

# and replot --> R now understand how to plot it!

plot(data$value~data$date)

# Easy to make it better now:

plot(data$value~data$date , type="b" , lwd=3 , col=rgb(0.1,0.7,0.1,0.8) , ylab="value of ..." , xlab="date" , bty="l" , pch=20 , cex=4)

abline(h=seq(0,100,10) , col="grey", lwd=0.8)

Not what you are looking for ? Make a new search !


				
					Search for:
					
				
				
			

3D abline add aggregate animation arrows at axis barplot basics beside bg border boxplot boxwex breaks bty cex cex.axis circular plot cmdscale col color Colors cor cut d3.js dataArt dendrogram density dist factor font ggplot ggplot2 hclust hist Histograms hiveplot horiz hsv ifelse Igraph image ImageMagick Important ! inset jitter labels las lattice layout leafletR legend legend.text levelplot levels library lines lm lty lwd main map Maps mar mfrow mfrox mgp Miscellaneous model mtext mtxt names nlevels oma order package par paste PCA pch pie plot plotly points polygon predict pt.cex pty R radarchart rect reorder rgb rgl Ring scatterplot segments stacked-area table tag_ tag_for_slider testnumber1 text tick Time series title toto tutu type VennDiagram violin-plot width wordcloud xaxt xlab xlim xyplot yaxt ylab ylim zetag 
You can search a media by theme with the tag cloud above.