Finding data on specific point from large set data
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I have a folder named 'THETHA'. Inside folder I have 360 csv file named '1.csv', '2.csv',...'360.csv'. Each csv file has a data of temperature for different location (X ,Y, Z ,T). Each csv file has different number of rows because result is generated from comsol. I want to estimate temperature on specific point in each csv file. I have made another folder named "DATA" which contains my specific point(X, Y ,Z) in which i want to estimate temperature in each csv file. It is possible that our specific point may not be in csv file so i need to find temperature on that point with the help of interpolation. I am attaching my 'DATA' file and one csv file. Please help me.
采纳的回答
- Import data (e.g. right click file -> Import data... -> generate code)
- Use scattered interpolant: Interpolating Scattered Data - MATLAB & Simulink (mathworks.com)
clear;
%%% get XYZ locations to interpolate
opts = delimitedTextImportOptions("NumVariables", 3);
opts.DataLines = [1, Inf];
opts.Delimiter = ",";
opts.VariableNames = ["VarName1", "VarName2", "VarName3"];
opts.VariableTypes = ["double", "double", "double"];
opts.ExtraColumnsRule = "ignore";
opts.EmptyLineRule = "read";
data = readtable("DATA.csv", opts);
XYZq = table2array(data);
%%% import data from a Theta file
clearvars opts;
opts = delimitedTextImportOptions("NumVariables", 4);
opts.DataLines = [10, Inf];
opts.Delimiter = ",";
opts.VariableNames = ["X", "Y", "Z", "TKThetha1"];
opts.VariableTypes = ["double", "double", "double", "double"];
opts.ExtraColumnsRule = "ignore";
opts.EmptyLineRule = "read";
data = readtable("1.csv", opts);
data = table2array(data);
% create a scattered interpolant object
T_data = scatteredInterpolant(data(:,1:3),data(:,4));
% interpolate the values
T_interp = T_data(XYZq)
12 个评论
AMAN GUPTA
2022-3-10
AndresVar
2022-3-10
@AMAN GUPTA that function maybe not be available on matlab 2018. Anyway use either:
- csvread instead: (Not recommended) Read comma-separated value (CSV) file - MATLAB csvread (mathworks.com)
- or use the import tool, and generate the code: Import data from file - MATLAB (mathworks.com)
AndresVar
2022-3-10
@AMAN GUPTA using csvread:
clear;
XYZq = csvread("DATA.csv");
data = csvread("1.csv",9);
% create a scattered interpolant object
T_data = scatteredInterpolant(data(:,1:3),data(:,4));
% interpolate the values
T_interp = T_data(XYZq)
AMAN GUPTA
2022-3-10
AMAN GUPTA
2022-3-10
AndresVar
2022-3-10
maybe something like this
XYZq = csvread("DATA.csv");
thetas = 1:360;
T_interp = zeros(size(XYZq,1),numel(thetas)) % a column for each theta
for ii = 1:numel(thetas)
theta = thetas(ii);
thetaFilename = sprintf("%d.csv",theta)
data = csvread(thetaFilename,9)
T_data = scatteredInterpolant(data(:,1:3),data(:,4));
T_interp(:,ii) = T_data(XYZq);
end
AMAN GUPTA
2022-3-11
AMAN GUPTA
2022-3-11
AndresVar
2022-3-12
you should verify 194.csv file exist and that the data on it starts at row 10 like the others
debug file 194 outside the loop. You can see the error is line 10, so it has problems reading that file.
AMAN GUPTA
2022-3-30
AndresVar
2022-3-30
what do the numbers represent?
Anyway, here is one way
XYZq = csvread("DATA.csv");
num1s = 1:71;
num2s = 1:41;
T_interp = nan(size(XYZq,1),numel(num1s),numel(num2s)) % 3 dimensions
for num1 = num1s
for num2 = num2s
dataFilename = sprintf("%d_%d.csv",num1,num2)
data = csvread(dataFilename,9)
T_data = scatteredInterpolant(data(:,1:3),data(:,4));
T_interp(:,num1,num2) = T_data(XYZq);
end
end
The alternative is you put the csv files in a folder and read all. for each file make a variable name and assignit in a table or struct. This would be useful if you don't know num1s and num2s
AMAN GUPTA
2022-3-30
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AMAN GUPTA
2022-4-10
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