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How do I write something to run this function?

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WARRIOR24
WARRIOR24 on 14 Dec 2020
Edited: Rik on 14 Dec 2020
I am relativitly new to MATLAB. Most of my new learnings have been learning how to write and run BASIC Functions. I downloaded this CRC32 bit function from File Exchange and I am having a hard time to run/callout the function.
I am trying to enter a HEX number and return the CRC Calculation in HEX.'
I am trying to calculate the CRC for something like "00060D00"
function crc = crc32(data)
%crc32 Computes the CRC-32 checksum value of a byte vector.
%--------------------------------------------------------------------------
% CRC = crc32(DATA) computes the CRC-32 checksum value of the data stored
% in vector DATA. The elements of DATA are interpreted as unsigned bytes
% (uint8). The result is an unsigned 32-bit integer (uint32). Polynomial
% bit positions have been reversed, and the algorithm modified, in order
% to improve performance.
% Version: 1.00
% Programmer: Costas Vlachos
% Date: 23-Dec-2014
% Initialize variables
crc = uint32(hex2dec('FFFFFFFF'));
poly = uint32(hex2dec('EDB88320'));
data = uint8(data);
% Compute CRC-32 value
for i = 1:length(data)
crc = bitxor(crc,uint32(data(i)));
for j = 1:8
mask = bitcmp(bitand(crc,uint32(1)));
if mask == intmax('uint32'), mask = 0; else mask = mask+1; end
crc = bitxor(bitshift(crc,-1),bitand(poly,mask));
end
end
crc = bitcmp(crc);
I saved it a new folder and path with nothing in there except this function (crc32.m)
When I click "Run" directly in the "Script" Tab/Window, this is what I get in the Command Window:
>> crc32
Not enough input arguments.
Error in crc32 (line 16)
data = uint8(data);
And takes me to the "Run" and shows this:
Can some explain this to me as well as how to call and use this function? Write a code? What I need to do to run and execute this funtion? How to enter?
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Accepted Answer

KALYAN ACHARJYA
KALYAN ACHARJYA on 14 Dec 2020
Edited: KALYAN ACHARJYA on 14 Dec 2020
crc32(data);
%......^??
You have to pass the input arguments (data) as mentioned in the function code. e.g.
>>data=[1:18]; % Pass the appropriate data type as per function defined??
>>crc32(data)
  8 Comments
Rik
Rik on 14 Dec 2020
As Walter mentioned: dec2hex will convert the value to hexadecimal without any issues.
dec2hex(crc32(data))
The function you showed doesn't handle array inputs by default, so you will have to use a loop to process your inputs one by one. It is also possible to use arrayfun to hide the loop.

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