Why is my program returning these two values?

[SS_9985257]

 

 

Relatively green Mathcad Prime 7 user here. I am trying to write a simple iteration program so that I can eventually try to adapt it for my needs. My question is: Why is my program returning 0 and 1 as well as multiplying everything by 1? I just want to see the values from 1..n where's f(n) is my input. I have minimal experience coding so I apologize if the answer is relatively easy or has been in front of my face the entire time. I will attach a file upload as well as a pictures, thanks in advance.

[StuartBruff]

The reason you are seeing a "0" is that Mathcad's default matrix index origin is zero.    When you assign a value to a nonexistent array, Mathcad creates the array, with you index being the last item in the new array.   Mathcad fills all previous undefined elements with zeros.

You've created an array R with index 1 at the start of your loop.   Mathcad creates the array R with index 1 and fills index 0 with zero (as per the array creation rules).   Interestingly, it doesn't complain about R not existing during the first assignment, so I'm guessing that it creates R as a single element array with index 0 before doing anything else.

So, at the end of the first iteration, you have an array with index 0 = 0 (autofill) and index 1 = 1.

However, at the next iteration, you set the array index 2 to be the entire current value of  R plus 1.  Hence the appearance of a 2x1 vector in index 2.   Similarly at each subsequent iteration, you add one to the the entire array.

To get a better picture of  what's happening, go to the Matrices/Tables tab and deselect the "Collapse Nested Matrices) button.   This should show all the values for each index of R.

What were you hoping that the result would be?

Stuart

[Werner_E]

Are you looking for something like this:

Note that all functions are written to be independent of the current setting of the system variable ORIGIN. This variable is set by default to 0 while I guess you think it should be 1.

[LucMeekes]

An alternative for ones4 (simpler, and works in express) and another possibility: ones5.

Although, I must admit, ones5 does not produce a vector, it only appears to be a vector.

Success!
Luc