How can I reshape date column in a dataframe?-CodePudding

I want to reshape my Date column in the same months-wise. For example, the first 12 rows in the Date column of the dataframe contains a character of all the months in the year 2001 and the respective year itself. The next rows are the same, until the year 2017.

Therefore. I want to reshape my data like the following. For example, I want all Januaries of the all years to be in the first rows of Date column, then all februaries in the next rows, Marches of the all years and so on, until December of all years (2001-2017)

I need like this format:

1  2001     1
2  2002     1
3  2003     1
4  2004     1
5  2005     1
6  2006     1
7  2007     1
8  2008     1
9  2009     1
10 2010     1
11 2011     1
12 2012     1
13 2013     1
14 2014     1
15 2015     1
16 2016     1
17 2017     1
18 2001     2
19 2002     2
20 2003     2
21 2004     2
22 2005     2
23 2006     2
24 2007     2

This is my dataframe I generated using dput()

 #load packages that might be required
> library(tidyverse)
> library(xts)

> # Read NDVI 
> NDVI <- read.csv("processed//NDVI.csv")
> dput(NDVI)
structure(list(Date = c("Jan 1, 2001", "Feb 1, 2001", "Mar 1, 2001", 
"Apr 1, 2001", "May 1, 2001", "Jun 1, 2001", "Jul 1, 2001", "Aug 1, 2001", 
"Sep 1, 2001", "Oct 1, 2001", "Nov 1, 2001", "Dec 1, 2001", "Jan 1, 2002", 
"Feb 1, 2002", "Mar 1, 2002", "Apr 1, 2002", "May 1, 2002", "Jun 1, 2002", 
"Jul 1, 2002", "Aug 1, 2002", "Sep 1, 2002", "Oct 1, 2002", "Nov 1, 2002", 
"Dec 1, 2002", "Jan 1, 2003", "Feb 1, 2003", "Mar 1, 2003", "Apr 1, 2003", 
"May 1, 2003", "Jun 1, 2003", "Jul 1, 2003", "Aug 1, 2003", "Sep 1, 2003", 
"Oct 1, 2003", "Nov 1, 2003", "Dec 1, 2003", "Jan 1, 2004", "Feb 1, 2004", 
"Mar 1, 2004", "Apr 1, 2004", "May 1, 2004", "Jun 1, 2004", "Jul 1, 2004", 
"Aug 1, 2004", "Sep 1, 2004", "Oct 1, 2004", "Nov 1, 2004", "Dec 1, 2004", 
"Jan 1, 2005", "Feb 1, 2005", "Mar 1, 2005", "Apr 1, 2005", "May 1, 2005", 
"Jun 1, 2005", "Jul 1, 2005", "Aug 1, 2005", "Sep 1, 2005", "Oct 1, 2005", 
"Nov 1, 2005", "Dec 1, 2005", "Jan 1, 2006", "Feb 1, 2006", "Mar 1, 2006", 
"Apr 1, 2006", "May 1, 2006", "Jun 1, 2006", "Jul 1, 2006", "Aug 1, 2006", 
"Sep 1, 2006", "Oct 1, 2006", "Nov 1, 2006", "Dec 1, 2006", "Jan 1, 2007", 
"Feb 1, 2007", "Mar 1, 2007", "Apr 1, 2007", "May 1, 2007", "Jun 1, 2007", 
"Jul 1, 2007", "Aug 1, 2007", "Sep 1, 2007", "Oct 1, 2007", "Nov 1, 2007", 
"Dec 1, 2007", "Jan 1, 2008", "Feb 1, 2008", "Mar 1, 2008", "Apr 1, 2008", 
"May 1, 2008", "Jun 1, 2008", "Jul 1, 2008", "Aug 1, 2008", "Sep 1, 2008", 
"Oct 1, 2008", "Nov 1, 2008", "Dec 1, 2008", "Jan 1, 2009", "Feb 1, 2009", 
"Mar 1, 2009", "Apr 1, 2009", "May 1, 2009", "Jun 1, 2009", "Jul 1, 2009", 
"Aug 1, 2009", "Sep 1, 2009", "Oct 1, 2009", "Nov 1, 2009", "Dec 1, 2009", 
"Jan 1, 2010", "Feb 1, 2010", "Mar 1, 2010", "Apr 1, 2010", "May 1, 2010", 
"Jun 1, 2010", "Jul 1, 2010", "Aug 1, 2010", "Sep 1, 2010", "Oct 1, 2010", 
"Nov 1, 2010", "Dec 1, 2010", "Jan 1, 2011", "Feb 1, 2011", "Mar 1, 2011", 
"Apr 1, 2011", "May 1, 2011", "Jun 1, 2011", "Jul 1, 2011", "Aug 1, 2011", 
"Sep 1, 2011", "Oct 1, 2011", "Nov 1, 2011", "Dec 1, 2011", "Jan 1, 2012", 
"Feb 1, 2012", "Mar 1, 2012", "Apr 1, 2012", "May 1, 2012", "Jun 1, 2012", 
"Jul 1, 2012", "Aug 1, 2012", "Sep 1, 2012", "Oct 1, 2012", "Nov 1, 2012", 
"Dec 1, 2012", "Jan 1, 2013", "Feb 1, 2013", "Mar 1, 2013", "Apr 1, 2013", 
"May 1, 2013", "Jun 1, 2013", "Jul 1, 2013", "Aug 1, 2013", "Sep 1, 2013", 
"Oct 1, 2013", "Nov 1, 2013", "Dec 1, 2013", "Jan 1, 2014", "Feb 1, 2014", 
"Mar 1, 2014", "Apr 1, 2014", "May 1, 2014", "Jun 1, 2014", "Jul 1, 2014", 
"Aug 1, 2014", "Sep 1, 2014", "Oct 1, 2014", "Nov 1, 2014", "Dec 1, 2014", 
"Jan 1, 2015", "Feb 1, 2015", "Mar 1, 2015", "Apr 1, 2015", "May 1, 2015", 
"Jun 1, 2015", "Jul 1, 2015", "Aug 1, 2015", "Sep 1, 2015", "Oct 1, 2015", 
"Nov 1, 2015", "Dec 1, 2015", "Jan 1, 2016", "Feb 1, 2016", "Mar 1, 2016", 
"Apr 1, 2016", "May 1, 2016", "Jun 1, 2016", "Jul 1, 2016", "Aug 1, 2016", 
"Sep 1, 2016", "Oct 1, 2016", "Nov 1, 2016", "Dec 1, 2016", "Jan 1, 2017", 
"Feb 1, 2017", "Mar 1, 2017", "Apr 1, 2017", "May 1, 2017", "Jun 1, 2017", 
"Jul 1, 2017", "Aug 1, 2017", "Sep 1, 2017", "Oct 1, 2017", "Nov 1, 2017", 
"Dec 1, 2017"), NDVI = c(0.722, 0.418, 0.435, 0.568, 0.616, 0.75, 
0.62, 0.516, 0.389, 0.484, 0.65, 0.7, 0.533, 0.327, 0.279, 0.43, 
0.701, 0.797, 0.748, 0.569, 0.597, 0.662, 0.794, 0.706, 0.537, 
0.338, 0.404, 0.461, 0.759, 0.76, 0.578, 0.408, 0.56, 0.62, 0.684, 
0.785, 0.539, 0.442, 0.307, 0.461, 0.593, 0.739, 0.674, 0.495, 
0.603, 0.712, 0.776, 0.665, 0.522, 0.333, 0.398, 0.28, 0.713, 
0.746, 0.757, 0.549, 0.711, 0.685, 0.693, 0.716, 0.617, 0.476, 
0.407, 0.325, 0.555, 0.757, 0.622, 0.544, 0.452, 0.586, 0.761, 
0.649, 0.635, 0.472, 0.351, 0.402, 0.662, 0.757, 0.712, 0.69, 
0.618, 0.632, 0.797, 0.778, 0.543, 0.401, 0.393, 0.556, 0.68, 
0.784, 0.659, 0.654, 0.412, 0.653, 0.694, 0.727, 0.715, 0.55, 
0.641, 0.443, 0.709, 0.818, 0.646, 0.59, 0.39, 0.562, 0.67, 0.56, 
0.476, 0.312, 0.349, 0.405, 0.705, 0.766, 0.665, 0.577, 0.614, 
0.518, 0.718, 0.779, 0.792, 0.547, 0.585, 0.373, 0.605, 0.715, 
0.779, 0.758, 0.751, 0.77, 0.752, 0.805, 0.521, 0.471, 0.561, 
0.595, 0.688, 0.74, 0.77, 0.69, 0.704, 0.613, 0.653, 0.803, 0.63, 
0.472, 0.589, 0.512, 0.562, 0.699, 0.814, 0.637, 0.395, 0.462, 
0.419, 0.742, 0.498, 0.35, 0.308, 0.321, 0.597, 0.677, 0.729, 
0.526, 0.394, 0.567, 0.806, 0.752, 0.703, 0.495, 0.453, 0.48, 
0.593, 0.731, 0.799, 0.619, 0.403, 0.396, 0.556, 0.743, 0.717, 
0.504, 0.408, 0.356, 0.215, 0.68, 0.487, 0.594, 0.392, 0.566, 
0.547, 0.632, 0.604, 0.528, 0.424, 0.627, 0.448, 0.788, 0.764, 
0.592, 0.517, 0.274, 0.577, 0.754)), class = "data.frame", row.names = c(NA, 
-204L))

CodePudding user response：

library(dplyr)
library(tidyr)
library(lubridate)
df %>%
  mutate(Date = mdy(Date)) %>%
  separate(Date, into = c("year", "month", "day"), remove = FALSE) %>%
  arrange(month, day, year)
#           Date year month day  NDVI
# 1   2001-01-01 2001    01  01 0.722
# 2   2002-01-01 2002    01  01 0.533
# 3   2003-01-01 2003    01  01 0.537
# 4   2004-01-01 2004    01  01 0.539
# 5   2005-01-01 2005    01  01 0.522
# 6   2006-01-01 2006    01  01 0.617
# ...

This is not generally called a "reshaping" operation - this is sorting/ordering/arranging rows. Reshaping/pivoting is when something that is a column becomes a row, or vice versa.