how to plot a time on x-axis and height on y-axis and data with respect to time
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i have a file that is having headerfile data headerfile data.............. in headerfile there is data ht u v w....... i want header seprate and i want to show the plot time(same time which is in text file)on x-axis which is in the headerfile and data u,v,z with respect to height on y-axis. i tried many times ,but time is passing no progress.could any one help me i want to show data is chaning with respect to time please give me program
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Accepted Answer
dpb
on 30 Apr 2014
Edited: dpb
on 1 May 2014
...the date and time is in the header...
Oh, ok...I'm not sure you said that the first go 'round. So, modify the previous to handle that
c=[]; % an empty array to collect data into
dn=[]; % ditto for date/time as Matlab datenum
fmt=repmat('%f',1,4); % format string for the numeric data 4/record
fid=fopen('31oct97.txt','r'); % open the file, return file handle
while ~feof(fid) % begin loop until run out of data in file
l=fgetl(fid); % skip that first line
ERRATA: An extra '%' before the \n in both format strings in original...fixed.
dmy=fscanf(fid,'Date : %2d/%2d/%2d\n').'; % get the d,m,y values
dmy(3)=dmy(3)+1900; % fixup the 2-digit year, put in y,m,d order
hms=fscanf(fid,'Time: %2d:%2d:%2d\n').'; % and h,m,s
dn=[dn;datenum([fliplr(dmy) hms])]; % convert to datenum
% now read a remaining data chunk/concatenate-resize header lines to skip
c=[c;cell2mat(textscan(fid,fmt,187,'headerlines',21))];
fgetl(fid);fgetl(fid); % and get the \n and blank line to repeat
end
I actually debugged the above on your file with the only difference being for brevity I just kept two sets of headers and five lines of data/set. The one difficulty you may run into is that I now see that the data are duplicated for each time at positions I guess(?) so instead of concatenating c as above you may prefer to keep each iteration as a plane in a 3D array to keep each directly associated with the group. Otherwise I guess you'd end up wanting to select into rows by the number/group.
To plot the time series, having dealt with that one way or another,
plot(dn,c(suitable_indices))
datetick('x')
See
doc datenum % and friends
doc datetick
for more details on display time axes.
4 Comments
dpb
on 1 May 2014
...how to plot a raw file (.r1)files into timeseries...
No klew...where's there a definition of the file format?
I'd suggest this might be a case for
doc memmapfile
however
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