datetick

Date formatted tick labels

Syntax

datetick(tickaxis)

datetick(tickaxis,dateFormat)

datetick(___,'keeplimits')

datetick(___,'keepticks')

datetick(axes_handle,___)

Description

Note

It is often more convenient to plot datetime values using the desired plotting function. Then you can format the tick labels using the xtickformat and ytickformat functions. datetick is useful when plotting numeric values that are serial date numbers.

datetick(tickaxis) labels the tick lines of the axis specified by tickaxis using dates, replacing the default numeric labels. datetick selects a label format based on the minimum and maximum limits of the specified axis. The axis data values should be serial date numbers, as returned by the datenum function.

datetick(tickaxis,dateFormat) formats the labels according to dateFormat.

datetick(___,'keeplimits') changes the tick labels to date-based labels while preserving the axis limits. Append 'keeplimits' to any of the previous syntaxes.

datetick(___,'keepticks') changes the tick labels to date-based labels while preserving their locations. Append 'keepticks' to any of the previous syntaxes.

datetick(axes_handle,___) labels the tick lines of an axis on the axes specified by axes_handle. The axes_handle argument can precede any of the input argument combinations in the previous syntaxes.

Examples

Label x-Axis Ticks with 2-digit Years

Graph population data for the 20th Century taken from the 1990 US census and label x-axis ticks with 2-digit years.

Create time data by decade.

t = (1900:10:1990)';

Enter total population counts for the USA.

p = [75.995 91.972 105.711 123.203 131.669 ...
	150.697 179.323 203.212 226.505 249.633]';

Convert years to serial date numbers using the datenum function, and then create a bar graph of the data.

figure
bar(datenum(t,1,1),p)

Replace x-axis ticks with 2-digit years. The numeric identifier 11 corresponds to the predefined MATLAB® date format 'yy'.

dateFormat = 11;
datetick('x',dateFormat)

Label x-Axis Ticks with Hours of the Day

Plot traffic count data against date ticks for hours of the day showing AM and PM.

Get traffic count data.

load count.dat

Create arrays for an arbitrary date, for example, April 18, 1995.

n = length(count);
year = repmat(1995,1,n);
month = repmat(4,1,n);
day = repmat(18,1,n);

Create arrays for each of 24 hours.

hour = 1:n;
minutes = zeros(1,n);

Get the serial date numbers for the date arrays.

sdate = datenum(year,month,day,hour,minutes,minutes);

Plot a 3-D bar graph of the traffic data against the serial date numbers.

bar3(sdate,count)

Label the tick lines of the graph's y-axis with the hours of the day.

datetick('y','HHPM')

Label x-Axis and Preserve Axis Limits

Select a starting date.

startDate = datenum('02-01-1962');

Select an ending date.

endDate = datenum('11-15-2012');

Create a variable, xdata, that corresponds to the number of years between the start and end dates.

xData = linspace(startDate,endDate,50);

Plot random data.

figure
stem(xData,rand(1,50))

Label the x-axis with 4-digit years, preserving the x-axis limits by using the 'keeplimits' option.

datetick('x','yyyy','keeplimits')

Add Month Labels to Plot and Preserve Number of Ticks

Select a starting date.

startDate = datenum('01-01-2009');

Select an ending date.

endDate = datenum('12-31-2009');

Create a variable, xdata, that corresponds to the number of months between the start and end dates.

xData = linspace(startDate,endDate,12);

Plot random data.

figure
stairs(xData,rand(1,12))

Set the number of XTicks to the number of points in xData.

ax = gca;
ax.XTick = xData;

Label the x-axis with month names, preserving the total number of ticks by using the 'keepticks' option.

datetick('x','mmm','keepticks')

Input Arguments

tickaxis — Axis to label

'x' (default) | 'y' | 'z'

Axis to label with dates, specified as 'x', 'y', or 'z'.

dateFormat — Format of tick line labels

character vector | integer

Format of the tick line labels, specified as a character vector of symbolic identifiers or an integer that corresponds to a predefined format.

The following table shows symbolic identifiers that you can use to construct the format. You can include characters such as a hyphen, space, or colon to separate the fields. For example, to display the day of the month followed by the three-letter abbreviation of the day of the week in parentheses, use dateFormat = 'dd (ddd)'.

Note

The letter identifiers that datetick accepts are different from the identifiers used by the datetime function.

Symbolic Identifier	Description	Example
yyyy	Year in full	1990, 2002
yy	Year in two digits	90, 02
QQ	Quarter year using letter Q and one digit	Q1
mmmm	Month using full name	March, December
mmm	Month using first three letters	Mar, Dec
mm	Month in two digits	03, 12
m	Month using capitalized first letter	M, D
dddd	Day using full name	Monday, Tuesday
ddd	Day using first three letters	Mon, Tue
dd	Day in two digits	05, 20
d	Day using capitalized first letter	M, T
HH	Hour in two digits (no leading zeros when symbolic identifier AM or PM is used)	05, 5 AM
MM	Minute in two digits	12, 02
SS	Second in two digits	07, 59
FFF	Millisecond in three digits	057
AM or PM	AM or PM inserted in text representing time	3:45:02 PM

The following table lists predefined MATLAB^® date formats.

Numeric Identifier	Date and Time Format	Example
-1 (default)	'dd-mmm-yyyy HH:MM:SS' or 'dd-mmm-yyyy' if 'HH:MM:SS'= 00:00:00	01-Mar-2000 15:45:17 or 01-Mar-2000
0	'dd-mmm-yyyy HH:MM:SS'	01-Mar-2000 15:45:17
1	'dd-mmm-yyyy'	01-Mar-2000
2	'mm/dd/yy'	03/01/00
3	'mmm'	Mar
4	'm'	M
5	'mm'	03
6	'mm/dd'	03/01
7	'dd'	01
8	'ddd'	Wed
9	'd'	W
10	'yyyy'	2000
11	'yy'	00
12	'mmmyy'	Mar00
13	'HH:MM:SS'	15:45:17
14	'HH:MM:SS PM'	3:45:17 PM
15	'HH:MM'	15:45
16	'HH:MM PM'	3:45 PM
17	'QQ-YY'	Q1-01
18	'QQ'	Q1
19	'dd/mm'	01/03
20	'dd/mm/yy'	01/03/00
21	'mmm.dd,yyyy HH:MM:SS'	Mar.01,2000 15:45:17
22	'mmm.dd,yyyy'	Mar.01,2000
23	'mm/dd/yyyy'	03/01/2000
24	'dd/mm/yyyy'	01/03/2000
25	'yy/mm/dd'	00/03/01
26	'yyyy/mm/dd'	2000/03/01
27	'QQ-YYYY'	Q1-2001
28	'mmmyyyy'	Mar2000
29	'yyyy-mm-dd' (ISO 8601)	2000-03-01
30	'yyyymmddTHHMMSS' (ISO 8601)	20000301T154517
31	'yyyy-mm-dd HH:MM:SS'	2000-03-01 15:45:17

Tips

• To change the tick spacing and locations, set the appropriate axes property (that is, XTick, YTick, or ZTick) before calling datetick.

• Calling datetick sets the TickMode of the specified axis to 'manual'. This means that after zooming, panning or otherwise changing axis limits, you should call datetick again to update the ticks and labels.

• The best way to work with dates and times in MATLAB is to use datetime values, which offer more features than serial date numbers. Plot datetime values using the plot function. Use the DatetimeTickFormat name-value pair argument to modify the format of the axis tick labels.

Algorithms

datetick calls the datestr function to convert date numbers to text.