Extract specific rows or columns containing letters (xxx) From dat File in Matlab

looking to come up with a script in matlab.the script should extract rows and columns containing/starting with letters xxx only in a dat file. This should be repeated for a number of DAT files. I have attached example xlsx file. for this example file I would like to extract any data that has the letters NSV. Any assist is welcomed. thanks in advance.

[Paolo]

 t = readtable('dta.xlsx','ReadVariableNames',false);
 C = table2cell(t);

 [tokens,matches] = cellfun(@(x) (regexp((x),'(.+)(?<=NSV)(.+)','match','tokens')),C,'un',0);
 tokens(cellfun(@(x) isempty(x),tokens)) = [];

tokens{:} =

 'BCS_PHY/FUN_OUT/ENV/HYD_NSV1_COIL1_CURRENT_OVERRIDE_OUTPUT'   
 'BCS_PHY/FUN_OUT/ENV/HYD_NSV1_COIL2_CURRENT_OVERRIDE_OUTPUT'   
 'BCS_PHY/FUN_OUT/ENV/HYD_NSV2_COIL2_CURRENT_OVERRIDE_OUTPUT'   
 'BCS_PHY/FUN_OUT/ENV/HYD_NSV2_COIL1_CURRENT_OVERRIDE_OUTPUT'   
 'BCS_PHY/FUN_OUT/ENV/HYD_NSV3_COIL1_CURRENT_OVERRIDE_OUTPUT'   
 'BCS_PHY/FUN_OUT/ENV/HYD_NSV3_COIL2_CURRENT_OVERRIDE_OUTPUT'   
 'BCS_PHY/FUN_OUT/ENV/HYD_NSV4_COIL1_CURRENT_OVERRIDE_OUTPUT'   
 'BCS_PHY/FUN_OUT/ENV/HYD_NSV4_COIL2_CURRENT_OVERRIDE_OUTPUT'   
 'BCS_PHY/FUN_OUT/ENV/HYD_NSV5_COIL1_CURRENT_OVERRIDE_OUTPUT'   
 'BCS_PHY/FUN_OUT/ENV/HYD_NSV5_COIL2_CURRENT_OVERRIDE_OUTPUT'   
 'BCS_PHY/FUN_OUT/ENV/HYD_NSV6_COIL1_CURRENT_OVERRIDE_OUTPUT'   
 'BCS_PHY/FUN_OUT/ENV/HYD_NSV6_COIL2_CURRENT_OVERRIDE_OUTPUT'   
 'BCS_PHY/FUN_OUT/ENV/HYD_NSV7_COIL1_CURRENT_OVERRIDE_OUTPUT'   
 'BCS_PHY/FUN_OUT/ENV/HYD_NSV7_COIL2_CURRENT_OVERRIDE_OUTPUT'   
 'BCS_PHY/FUN_OUT/ENV/HYD_NSV8_COIL1_CURRENT_OVERRIDE_OUTPUT'   
 'BCS_PHY/FUN_OUT/ENV/HYD_NSV8_COIL2_CURRENT_OVERRIDE_OUTPUT'   
 'BCS_PHY/FUN_OUT/ENV/HYD_NSV9_COIL1_CURRENT_OVERRIDE_OUTPUT'   
 'BCS_PHY/FUN_OUT/ENV/HYD_NSV9_COIL2_CURRENT_OVERRIDE_OUTPUT'   
 'BCS_PHY/FUN_OUT/ENV/HYD_NSV10_COIL1_CURRENT_OVERRIDE_OUTPUT'   
 'BCS_PHY/FUN_OUT/ENV/HYD_NSV10_COIL2_CURRENT_OVERRIDE_OUTPUT'   
 'BCS_PHY/FUN_OUT/ENV/HYD_NSV11_COIL1_CURRENT_OVERRIDE_OUTPUT'   
 'BCS_PHY/FUN_OUT/ENV/HYD_NSV11_COIL2_CURRENT_OVERRIDE_OUTPUT'   
 'BCS_PHY/FUN_OUT/ENV/HYD_NSV12_COIL2_CURRENT_OVERRIDE_OUTPUT'   
 'BCS_PHY/FUN_OUT/ENV/HYD_NSV12_COIL1_CURRENT_OVERRIDE_OUTPUT'

Is this the desired output?

[victor Mwarumba]

@paolo I get an error message does not recognise the Readtable ? but yes it is the output I want plus the corresponding data for each NSV.

[Paolo]

What Matlab version are you running? By the "corresponding data", you mean all the data contained in the column where each entry is found?

[victor Mwarumba]

yes it was the matlab version works on R2016 but not R2013. yes i mean from each time step there is a corresponding NSV data which I would like to extract.

[Paolo]

@victor I have submitted an answer to your question. The output data contains the information you require. I also explain how you can programmatically change the combination of characters the code looks for. If the problem has been solved you can mark the question as accepted.

Answer 1

[Paolo]

The code below reads the xlsx file as a table t using readtable and converts it to a cell array C with table2cell . It uses cellfun and regexp to determine which cells in C contain 'NSV'. Find is used to determine the row and column of each entry in tokens in the cell array C.

If you need to match three different combinations of letters, replace 'NSV' in the regexp with said combination. If you need to do it programmatically, you can use strcat to obtain the expression string used for the regexp.

 t = readtable('dta.xlsx','ReadVariableNames',false);
 C = table2cell(t);

 [tokens,matches] = cellfun(@(x) (regexp((x),'(.+)(?<=NSV)(.+)','match','tokens')),C,'un',0);
 [row,col] = find(cellfun(@(x) ~isempty(x),tokens));

 data = C(row:end,col);

The first row of data is the char vectors which contain 'NSV', where the following rows contain all the corresponding data.

Sample output, first column of data:

 'BCS_PHY/FUN_OUT/ENV/HYD_NSV1_COIL1_CURRENT_OVERRIDE_OUTPUT'
 '0'
 '0'
 '0.012293'
 '0.012293'
 '-0.024586'
 ...
 ...
 ...

Sample output, second column of data:

 'BCS_PHY/FUN_OUT/ENV/HYD_NSV1_COIL2_CURRENT_OVERRIDE_OUTPUT'
 '0.012305'
 '0'
 '0.012305'
 '0'
 '-0.024611'
 ...
 ...
 ...

[victor Mwarumba]

thank you that's what I wanted hope the readtable will work for .dat file ?

[Paolo]

Should work fine, .dat is supported by readtable.