CJ - Adding several consecutive floating points

[Jose76 0]

Hi everybody!

I have several REAL data stored in consecutive addresses, for example, in D100, D102, D104,..., D110 and I want to sum it all and store it in another address, for example, on D200, but I haven't find an elegant way to do it.

In fact, I need a SUM(184) instruction but, for floating point instead of byte.

Can you help me?

Thank you!

[chelton 66]

How big is your range of floating point numbers? Do they need to be added every scan? 

D100 - D110 is only 5 floating point registers. Easily done with 4 +F(454) floating point additions. You won't get any more efficient than that. However if you were adding 10 or more  consecutive registers you may want to look at pointers/indirect addressing. Then you can choose if they are all added in 1 scan with a "FOR" loop or over consecutive scans.

[Ctor 2]

Instruction "+F"

And you can do an array and sum them using FOR. Or indirect addressing. 

[pfort 20]

I would do a Structure Text FB.

[Jose76 0]

Sorry for the delay, I was suppossed to receive an email when an answer was received ...

I'm about to add 10-20 numbers. I've been thinking about a indirect addresing and a FOR instruction, but I don't know how to use indirect addressing neither with contacts or structured text. In fact, I haven´t been able to write the @ symbol in the arguments of a +F instruction and don't knwo why.

Can you write a little example on how to do any of these?

Thank you!

[photovoltaic 121]

Here is summing D10 to D50 (20 floating point values)

 

The way I did it requires 1 extra loop hence the 21 in the FOR loop because I increment the index after adding. You may write yours differently.

[Sergei Troizky 26]

In my opinion, 20 instructions do not worth organizing a loop, not to mention FB.
Configure the output instructions to be shown horizontally, and 19-instruction rung will be of reasonable size.
And each register value will be on the screen for immediate monitoring.

Edited 11 Feb 2023 by Sergei Troizky