MATLAB: Data Reduction and sub set of data

circledata reduction projectMapping Toolbox

Hello every body,

I'm new with Matlab. I want to write a code whcih can be used on my grid file to reduce it to region of my interest. I have lat lon and displacement values. I want to define a circle of radius 100Km from a central point(lat lon) so that everything outside the circle delete and I get a resultant grid file with data of my own interest.

I would like to pay some reward (as Im a student) for this work.

Please let me know if anybody is interested

Thanks

Best Answer

Save some money and see the FAQ: http://matlab.wikia.com/wiki/FAQ#How_do_I_create_a_circle.3F

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numbers = xlsread('test.xls');
lats = numbers(:, 1);
lons = numbers(:, 2);
z = numbers(:, 3);
lat1 = 58.4
lon1 = 26.1
z1 = 1.65
lat2 = 58.5
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z2 = 1.11
desiredLats = lats >= lat1 & lats <= lat2
desiredLons = lons > lon1 & lons <= lon2
desiredZs = z <= z1  & z >= z2
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The slowdown is due to the large number of graphics objects created by the script -- each call to "plotm" creates a separate graphics object which needs to be initialized and maintained in memory.

If you are plotting individual points with no connections between them, consider using the "scatterm" function instead.

scatterm(lat, lon);

If you are plotting groups of points (such as polygons) that should have connections between them, you can concatenate the data for each group into a single vector and separate the groups with NaN values:

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lon1 = [0 0 10 10 0];
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Best Answer

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