Convert TS object to data.frame object

Question

I have been trying to figure out how to convert ts object to a data.frame, so that I can plot it in ggplot. Anyone have some great ideas how this is done? Here's how the ts object looks like

> austres
        Qtr1    Qtr2    Qtr3    Qtr4
1971         13067.3 13130.5 13198.4
1972 13254.2 13303.7 13353.9 13409.3
1973 13459.2 13504.5 13552.6 13614.3
1974 13669.5 13722.6 13772.1 13832.0
1975 13862.6 13893.0 13926.8 13968.9
1976 14004.7 14033.1 14066.0 14110.1
1977 14155.6 14192.2 14231.7 14281.5
1978 14330.3 14359.3 14396.6 14430.8
1979 14478.4 14515.7 14554.9 14602.5
1980 14646.4 14695.4 14746.6 14807.4
1981 14874.4 14923.3 14988.7 15054.1
1982 15121.7 15184.2 15239.3 15288.9
1983 15346.2 15393.5 15439.0 15483.5
1984 15531.5 15579.4 15628.5 15677.3
1985 15736.7 15788.3 15839.7 15900.6
1986 15961.5 16018.3 16076.9 16139.0
1987 16203.0 16263.3 16327.9 16398.9
1988 16478.3 16538.2 16621.6 16697.0
1989 16777.2 16833.1 16891.6 16956.8
1990 17026.3 17085.4 17106.9 17169.4
1991 17239.4 17292.0 17354.2 17414.2
1992 17447.3 17482.6 17526.0 17568.7
1993 17627.1 17661.5

Have a look at http://stackoverflow.com/questions/5331901/transforming-a-ts-in-a-data-frame-and-back — alexwhan, Feb 24 '13 at 08:01

agstudy · Accepted Answer · 2014-02-27T16:13:10.427

2

here a way. The idea is to reshape your time series in the long format. Here I am using reshape2 to melt the data.

I create my time series , Note the frequency here

dat <- ts(rnorm(12*5, 17, 8), start=c(1981,1), frequency = 4)

Than i put my data in the long format

library(reshape2)
library(zoo)
dat.m <- data.frame(yr=index(dat),value=melt(dat)$value)

I plot the result :

library(ggplot2)
qplot(x=yr,y=value,data=dat.m,geom='line')

enter image description here

edited Feb 27 '14 at 16:13

answered Feb 24 '13 at 08:15

agstudy

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I would like to use this solution. But that just doesn't work. Error in data.frame(yr = index(dat), value = melt(dat)$value) : could not find function "index" – tagoma Feb 27 '14 at 16:05
thx. i was trying replacing index() with time() and got some results – tagoma Feb 27 '14 at 16:24

score 1 · Answer 2 · answered Feb 24 '13 at 09:17

There is a zoo method for ggplot2's autoplot function:

# first create some sample data
library(ggplot2)
library(zoo)
tt <- ts(rnorm(100), freq = 4, start = c(1971, 2)) # sample data

# convert to zoo and plot
z <- as.zoo(tt)
autoplot(z)

or a bit fancier (shown below):

 autoplot(z) + 
    geom_vline(xintercept = time(z)[cycle(z) == 1], col = "grey", alpha = .7)

enter image description here

Convert TS object to data.frame object

2 Answers2