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10-Marble
Aug 17, 2026 9:57 PM UTC
Solved

How generate a cumulative sum sequence funtions

i Have PTC MATHCAD PRIME
 need a function to generate a cumulative sum sequence where Ui=0 and Ui-1 =0, iteratively calculating Ui+1 up to a 4094 rows , 1column vector.

 

Werner_E
Werner_EAnswer
25-Diamond I
Aug 18, 2026 12:22 AM UTC

Here is how I interpreted the iteration in your question. But the results differ from the ones you posted so it may help if you show step by step how to arrive at -9.00704*10^-6 and 3.37999*10^-5 using the values for P, A, B and K shown in your screenshot.:

 

9 replies

Werner_E
Werner_E25-Diamond IAnswer
25-Diamond I
Aug 18, 2026 12:22 AM UTC

Here is how I interpreted the iteration in your question. But the results differ from the ones you posted so it may help if you show step by step how to arrive at -9.00704*10^-6 and 3.37999*10^-5 using the values for P, A, B and K shown in your screenshot.:

 

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pannus010-MarbleAuthor
10-Marble
Aug 18, 2026 5:54 PM UTC

here ist’s 
It starts with 0, assumed initial value

second rows:

third

 

and so on until completing 4094 rows, because "origin=0"

 

 

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Werner_E
25-Diamond I
Aug 18, 2026 9:55 PM UTC

I don’t care about and will not look at just pictures(!) from an Excel sheet.

What I meant was that you show in Mathcad or Prime how to arrive at the first two non-zero values in vector u which you show in your first Excel screenshot by using just the numbers for P, A, B and K which you show in your first screenshot. I mean using the numbers with just the precision you had shown and which I  also used in my screenshot.

Simply show the manual calculation in Mathcad/Prime, the first two iteration steps, which you have in mind and show that you arrive at the values you has shown.

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19-Tanzanite
Aug 18, 2026 12:57 PM UTC

There is a more fundamental problem:

Units problem

 

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pannus010-MarbleAuthor
10-Marble
Aug 18, 2026 5:30 PM UTC

this is the ecu.

Ecu.

 

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19-Tanzanite
Aug 19, 2026 7:05 AM UTC

Apologies, my mistake, the units are the same. 

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