MATLAB: Remove all the spaces from a string.

forisspacemat2str

I have a string:

Pre_CRC = '[1 0 1 0 1 1 1 1 0 1 0 1 0 0 1 0]'

I need to convert this into a string to convert it into a unintialized binary number.

A = [msg_FCS(1,16385),msg_FCS(1,16386),msg_FCS(1,16387),msg_FCS(1,16386),msg_FCS(1,16387),...
    msg_FCS(1,16388),msg_FCS(1,16389),msg_FCS(1,16390),msg_FCS(1,16391),msg_FCS(1,16392),...
    msg_FCS(1,16393),msg_FCS(1,16394),msg_FCS(1,16395),msg_FCS(1,16396),msg_FCS(1,16397),...
    msg_FCS(1,16398),msg_FCS(1,16399),msg_FCS(1,16400)];
Pre_CRC = (mat2str(A));
Trim_CRC = zeros(1,16);
Trim_CRC_Counter = 1;
    for dd = 1:length(Pre_CRC)
          if (isspace(Pre_CRC(:,dd)) == 1)
              Pre_CRC(:,dd) = [];
          else
              Pre_CRC(1,dd) = Trim_CRC(1,Trim_CRC_Counter);
              Trim_CRC_Counter = Trim_CRC_Counter + 1; 
          end
    end

The end needs to be a string with the binary values that I can convert to a decimal or hex number. The two for loop above is giving me a matrix out of bounds errors. Can anyone help me fix this?

Thanks !

Best Answer

Pre_CRC(isspace(Pre_CRC)) = []

Related Solutions

MATLAB: How to configure crc.generator object from to implement X.25 Standard Cyclic Redundancy Check (CRC) coding with the Communications Toolbox 4.4 (R2009b)

The capability of directly generating X.25 Frame Checking Sequence using the GENERATE method of CRC.GENERATOR object is not available in Communications Toolbox 4.4 (R2009b).

However, the X.25 standard can be implemented using the crc.generator object. By default, crc.generator object is a CRC-CCITT generator, which is what X.25 implementation uses. However, X.25 does something extra, which is described in Section 2.2.7.4 of the X.25 documentation:

 The FCS field shall be a 16-bit sequence. It shall be the ones complement of the sum (modulo 2) of:
 1) the remainder of xk (x15 + x14 + x13 + x12 + x11 + x10 + x9 + x8 + x7 + x6 + x5 + x4 + x3 + x2 + x + 1) divided (modulo 2) by the generator polynomial x16 + x12 + x5 + 1, where k is the number of bits in the frame existing between, but not including, the final bit of the opening flag and the first bit of the FCS, excluding bits (synchronous transmission) or octets (start/stop transmission) inserted for transparency, and bits inserted for transmission timing (i.e. start or stop bits); and
 2) the remainder of the division (modulo 2) by the generator polynomial x16 + x12 + x5 + 1 of the product of x16 by the content of the frame, existing between but not including, the final bit of the opening flag and the first bit of the FCS, excluding bits (synchronous transmission) or octets (start/stop transmission) inserted for transparency and bits inserted for transmission timing (i.e. start or stop bits).

As a workaround, the following code implements X.25 standard using crc.generator object:

% Input
Address = [1 1 0 0 0 0 0 0];
UA = [1 1 0 0 1 1 1 0];
Input = [Address UA]';
% Expected FCS
FCS = [1 1 0 0 1 1 0 0 0 0 1 0 0 1 1 0];
k = length(Input);
h = crc.generator;
% Remainder of step 1)
cw1 = generate(h,[ones(16, 1); zeros(k-16,1)]);
% Remainder of step 2)
cw2 = generate(h,Input);
% Add the remainders and complement:
Workaround_FCS = not(mod(cw1(end-16+1:end) + cw2(end-16+1:end),2))';
% The result matches the FCS of X.25 standard test sequence
isequal(FCS,Workaround_FCS)

MATLAB: Loop to create 3×3 matrix for each frame

Does this do what you want:

R.fcsR = zeros(3,3,247);
for i = 1:247
    R.fcsR(:,:,i) = [Xn.fcsR(i,:); Yn.fcsR(i,:); Zn.fcsR(i,:)];
end

Best Answer

Related Solutions

MATLAB: How to configure crc.generator object from to implement X.25 Standard Cyclic Redundancy Check (CRC) coding with the Communications Toolbox 4.4 (R2009b)

MATLAB: Loop to create 3×3 matrix for each frame

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