Plotting 'HH:MM' format times against the X axis

I have a string of 'HH:MM' times that are based off of a set of decimal times. I really want to make a plot that displays my 'HH:MM' times though.

% taking my times (zero to 23:50 in ten minute incriments) and converting
% to decimal then 'HH:MM' format
decimalTimes = zeros(length(times),1);

for k = 1:length(times)
    hhTimes = floor(times(k)/100);  
    mmTimes = rem(times(k), 100)/60;    
    decimalTimes(k) = hhTimes + mmTimes;   
end

dateTimes = datestr(decimalTimes/24, 'HH:MM');

plot(decimalTimes,speeds,'s-r','LineWidth',lw);

% plot formatting
hold on
legend('10 minute average wind speeds for Dec. 24, 2011', 'Location', 'NorthEast','FontSize',legv);
title("Average Wind Speeds every 10 Minutes for One Full Day")
xlabel("Time (10 minute incriments)")
ylabel("Average Wind Speed")
hold off

Now from here absoluteley nothing I am trying is working to get the x axis to display times in the 'HH:MM' format. Please help.

Answer 1

[Voss]

times = (0:24*6-1)*10

times = 1×144

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200 210 220 230 240 250 260 270 280 290

speeds = rand(size(times));
lw = 2;
legv = 11;

dateTimes = datetime(2011,12,24,0,times,0, 'Format','HH:mm')

dateTimes = 1×144 datetime array
Columns 1 through 24

   00:00   00:10   00:20   00:30   00:40   00:50   01:00   01:10   01:20   01:30   01:40   01:50   02:00   02:10   02:20   02:30   02:40   02:50   03:00   03:10   03:20   03:30   03:40   03:50

Columns 25 through 48

   04:00   04:10   04:20   04:30   04:40   04:50   05:00   05:10   05:20   05:30   05:40   05:50   06:00   06:10   06:20   06:30   06:40   06:50   07:00   07:10   07:20   07:30   07:40   07:50

Columns 49 through 72

   08:00   08:10   08:20   08:30   08:40   08:50   09:00   09:10   09:20   09:30   09:40   09:50   10:00   10:10   10:20   10:30   10:40   10:50   11:00   11:10   11:20   11:30   11:40   11:50

Columns 73 through 96

   12:00   12:10   12:20   12:30   12:40   12:50   13:00   13:10   13:20   13:30   13:40   13:50   14:00   14:10   14:20   14:30   14:40   14:50   15:00   15:10   15:20   15:30   15:40   15:50

Columns 97 through 120

   16:00   16:10   16:20   16:30   16:40   16:50   17:00   17:10   17:20   17:30   17:40   17:50   18:00   18:10   18:20   18:30   18:40   18:50   19:00   19:10   19:20   19:30   19:40   19:50

Columns 121 through 144

   20:00   20:10   20:20   20:30   20:40   20:50   21:00   21:10   21:20   21:30   21:40   21:50   22:00   22:10   22:20   22:30   22:40   22:50   23:00   23:10   23:20   23:30   23:40   23:50

plot(dateTimes,speeds,'s-r','LineWidth',lw);

% plot formatting
hold on
legend('10 minute average wind speeds for Dec. 24, 2011', 'Location', 'NorthEast','FontSize',legv);
title("Average Wind Speeds every 10 Minutes for One Full Day")
xlabel("Time (10 minute increments)")
ylabel("Average Wind Speed")
hold off

Answer 2

[Star Strider]

I am not certain what ‘decimal times’ are, however it appears that they might be something like ‘HHMM’ where all are four-digit integers.

If so, try this —

times = [1100; 1115; 1130; 1145; 1200; 1215; 1230; 1245; 1300]

times = 9×1

1100 1115 1130 1145 1200 1215 1230 1245 1300

dateTimes = datetime(string(times), 'InputFormat','HHmm', 'Format','HH:mm')

dateTimes = 9×1 datetime array
   11:00
   11:15
   11:30
   11:45
   12:00
   12:15
   12:30
   12:45
   13:00

y = sin((0:numel(dateTimes)-1)*2*pi/(numel(dateTimes)-1));

figure
plot(dateTimes, y)
grid
xsecondarylabel("");

.

Answer 3

[Stephen23]

"taking my times (zero to 23:50 in ten minute incriments) and converting to decimal then 'HH:MM' format"

Do not convert to "decimal".

Do not use deprecated DATESTR or DATENUM or DATEVEC.

Do not use inappropriate DATETIME.

Plot using the DURATION type, it is the correct tool for the job:

% fake data
dur = minutes(0):minutes(10):minutes(24*60-1);
dur.Format = 'hh:mm';
vec = rand(1,numel(dur));
% plot
plot(dur,vec)

To adjust how many tickmarks there are use the tickmark controls e.g. XTICKS.