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Plotting Temperature with respect to time in MATLAB from a file??

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Hello!!! Everyone,
I am making a Data Logger Project and had stored Log in Memory Card, and wants to plot the Temperature Data with Respect to time in MATLAB.
18:30:04-> Time
05/10/13-> Date
025.7C -> Unit Temperature
+024.8C -> Atmosphere Temperature
058.7% -> Relative Humidity
Rest are Not useful
Can any one tell how to plot Temperature w.r.t time for each day on Separate graphs(Figure in MATLAB)
Please Help

Accepted Answer

Walter Roberson
Walter Roberson on 7 Oct 2013
fid - fopen('YourFile.txt');
datacell = textscan(fid, '%s%s%fC%fC%f%*[^\n]', 'Delimiter', ',');
fulldates = strcat(datacell{2}, {' '}, datacell{1});
datenumbers = datenum(fulldates, 'mm/dd/yy HH:MM:SS');
unittemps = datacell{3};
atmtemps = datacell{4};
relhums = datecell{5};
fig1 = figure();
ax1 = axes('Parent', fig1);
plot(datenumbers, unittemps, 'Parent', ax1);
datetick(ax1, 'x', 'HH:MM:SS');
title(ax1, 'Time vs Unit Temperature, Uni');
The refinement after this would be to split it down to individual days. For example as a quick hack:
datechars = char(datacell{2});
differentdates = any(diff(datchars, 1), 2);
Then differentdates will be true at location K if the K'th date differs from the (K+1)'th date and so indicates that you should split after the K'th row. Note that the result will be one element shorter than the number of row entries.

More Answers (1)

Arun Sharma
Arun Sharma on 7 Oct 2013
Edited: Walter Roberson on 7 Oct 2013
I had attached the file, and its not working
I found some errors like
fid = fopen('YourFile.txt');
datacell = textscan(fid, '%s%s%fC%fC%f%*[^\n]', 'Delimiter', ',');
I will try to use your code.
Can i use datetick function in MATLAB for solving my problem
Arun Sharma
Arun Sharma on 10 Oct 2013
Thank You So Much, I tried your method and it works. :-)
Here is the Code i wrote.
fid = fopen('LOGGER.CSV','r');
DataCell = textscan(fid,'%s %s %fC %fC %f%*[^\n]',1329,'Delimiter',',')
FullDate = strcat(DataCell{2},{' '},DataCell{1})
DateNumbers = datenum(FullDate,'mm/dd/yy HH:MM:SS')
UnitTemp = DataCell{3}
AtmTemp = DataCell{4}
Humidity = DataCell{5}
fig figure1
fig1 = figure();
ax1 = axes('Parent',fig1)
grid on
axis([min(DateNumbers) max(DateNumbers) 20 30])
ylabel('Temperature \rightarrow');
title('Temperature Graph 5th October');
Can You Explain me the meaning of this line
DataCell = textscan(fid,'%s %s %fC %fC %f%*[^\n]',1329,'Delimiter',',')
This part [^\n], although i know what it is doing but still wants to know this notation.
And Also the meaning of this line.
ax1 = axes('Parent',fig1)
Thank You Much, You method is perfect one.

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