what does this formula do ?

[Joseph 0028 0]

I have the below formula in CPT instruction (not able to attach any pics)... 

IO_Rmc_Data = (IO_Rmc_Data+1) MOD 10

What does MOD 10, MOD 1000, MOD 10000 do ? On help it says it stores the remainder of division, but here its doing something else. 

[chelton 66]

I would assume IO_Rmc_Data is an index for a 10 element array of Data.

The forrmula is creating a repeating 0-9 output. So if when IO_Rmc_Data = 9 , the next time the CPT is executed (IO_Rmc_Data+1) MOD 10, would equate to 10 MOD 10 which = 0

Edited 24 Feb 2021 by chelton
rephrase

[Joseph 0028 0]

1 hour ago, chelton said:

I would assume IO_Rmc_Data is an index for a 10 element array of Data.

The forrmula is creating a repeating 0-9 output. So if when IO_Rmc_Data = 9 , the next time the CPT is executed (IO_Rmc_Data+1) MOD 10, would equate to 10 MOD 10 which = 0

yes, you are right. Actually IO_Rmc1:O.Data[0] is an array of Real[124], and we have the formula IO_Rmc1:O.Data[0]=(IO_Rmc1:O.Data[0]+1)MOD1000.

So I believe we increment IO_Rmc1:O.Data[0] from 0 to 999 and then repeat ?