MATLAB: How to extract only floating numbers from a string

extract numberssscanfstrings

Here is my string "21.5VgDC_0.05000V_VgAC_50M-150M30ms47GV1" How can I extract only the numbers 21.5, 0.05000, 50, 150 30 and 47 from the string. Thanks in advance

Best Answer

>> S = '21.5VgDC_0.05000V_VgAC_50M-150M30ms47GV1';
>> C = regexp(S,'\d+\.?\d*','match');
>> C{:}
ans = 21.5
ans = 0.05000
ans = 50
ans = 150
ans = 30
ans = 47
ans = 1

Related Solutions

MATLAB: How to create matrix with fixed sum in rows and fixed increment in elements

Straightforward exhaustive search which does not generate any superfluous rows:

V = 0:5:100;
Z = nan(0,3);
for n1 = V
    for n2 = V
        for n3 = V
            if (n1+n2+n3)==100
                Z(end+1,:) = [n1,n2,n3];
            end
        end
    end
end
Z = Z/100;

This gives all 231 unique rows:

>> Z
Z =
 0.00000   0.00000   1.00000
 0.00000   0.05000   0.95000
 0.00000   0.10000   0.90000
 0.00000   0.15000   0.85000
 0.00000   0.20000   0.80000
 0.00000   0.25000   0.75000
 0.00000   0.30000   0.70000
 0.00000   0.35000   0.65000
 0.00000   0.40000   0.60000
 0.00000   0.45000   0.55000
 0.00000   0.50000   0.50000
 0.00000   0.55000   0.45000
 0.00000   0.60000   0.40000
 0.00000   0.65000   0.35000
 0.00000   0.70000   0.30000
... lots of rows here
 0.85000   0.05000   0.10000
 0.85000   0.10000   0.05000
 0.85000   0.15000   0.00000
 0.90000   0.00000   0.10000
 0.90000   0.05000   0.05000
 0.90000   0.10000   0.00000
 0.95000   0.00000   0.05000
 0.95000   0.05000   0.00000
 1.00000   0.00000   0.00000
>> size(Z)
ans =
   231     3
>> size(unique(Z,'rows'))
ans =
   231     3

MATLAB: Wrong rational numbers generated by Matlab

Hum:

>> rats(23/52)
ans =
    '     23/52    '

So, no issue there.

Of course, 23/52 is not equal to 0.4423, so if you give a rounded down input of 0.4423, why would you expect 23/52 when 1100/2487 is actually closer in value:

>> 23/52 - .4423
ans =
      7.69230769226414e-06
      
>> 1100/2487 - 0.4423
ans =
     -4.02090872819727e-08

Note:

>> format longg
>> 23/52
ans =
         0.442307692307692

Best Answer

Related Solutions

MATLAB: How to create matrix with fixed sum in rows and fixed increment in elements

MATLAB: Wrong rational numbers generated by Matlab

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