MATLAB: How to pass a hexadecimal number, generated in MATLAB workspace, as an input to the C-MEX routine

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How do I pass a hexadecimal number, that was generated in MATLAB workspace, as an input to my C-MEX routine?

I am generating a hexadecimal number in MATLAB using the DEC2HEX function. I want to pass this hexadecimal number to a C MEX routine. How do I pass a hexadecimal number to my MEX routine and how do I interpret it in my C code?

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The MATLAB function DEC2HEX returns the hexadecimal representation of a decimal integer as a string. If this value is passed as an argument to your MEX routine, it will be passed as a string and not as a hexadecimal number. In the C-MEX routine, you will need to parse the string and write your own routine to convert this string into a hexadecimal number.

Similarly, if you want to pass a hexadecimal number from C to MATLAB, you will have to pass the string representation of the hexadecimal number to MATLAB. You can then use HEX2DEC function to convert the string into a decimal number.

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C     Call the computational subroutine.
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    C-----------------------------------------------------------------------
    C     Computational subroutine
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You can't if you continue to use xlsread() since it has to launch and shutdown Excel every time. You need to use ActiveX programming. See my demo attached below in blue text. Run it for a demo of how to create, and how to read in Excel workbooks using ActiveX programming. It might look daunting at first but don't be scared. You're a smart engineer and you can handle it. It's well commented to explain every step of the way. It's something you'll need to learn eventually anyway.

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