One column times the transpose of itself 
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Assume that we have a set of values and we want to estimate the sum of their squared value. 

  Here is a example. We have 1, 3, 5 and 10. We want to estimate 1^2 + 3^2 + 5^2 and 10^2=?

    we generate a column and assume that they are in A1 to A4. 
       1
       3 
       5
       10

     =mmult(transpose(A1:A4,A1:A4))

   After hit Ctrl-Shift-Enter, we will see 135 appear in the cell. 

   The following would appear in the formula bar. 

      {=MMULT(TRANSPOSE(A1:A4),A1:A4)}

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One column times the transpose of another column 
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   If we have the same number of values for both column then we 

         could use the following formula 


   =mmult(transpose(column1),column2)

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Who owns code written by Chat GPT
///////////////////////////////////////////
 Who owns code written by Chat GPT?
    The question of code ownership when it's generated by AI is a complex and
    evolving issue, involving both ethical and legal considerations. 

 However,as a general principle, the ownership of the code generated by 
    ChatGPT is usually attributed to the person or entity who provided 
    the specific instructions or problem that led to the generation of the code.

 Think of it this way: if a programmer uses a tool to write code, they own the 
    resulting code, not the tool's manufacturer. Similarly, when using ChatGPT, 
    the user inputs the data or problem, and ChatGPT generates the code based on 
    that input. Thus, the resulting code is typically considered the intellectual
    property of the user.
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This is for e10(20) VBA issue.
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If "Developer" is not available on your menu bar

    Step 1: click 'File', 

    Step 2: click 'Options' 

    Step 3: click 'Customize Ribbon' 

    Step 4: Activate 'developer' and click 'OK'

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