How to calculate values in two fields ?

[mah]

hi,

My issue is I have a table like that :

field 1	field 2
1	0
2	1
2	2
1	0

I want to create an third column that create the result of :

first line = field1 - field2=field3

second line = first line field3 + second line field1 -  second line field2=new field3

third line = second line field3 + third line field1 -  third line field2=new field3

etc...

field 1	field 2	field 3
1	0	1
2	1	2 (1+2-1)
1	2	1 (2+1-2)
1	0	2 (1+1-0)

Can you help me ? 

Thanks!

[ITWhisperer]

| autoregress field_3
| fillnull value=0 field_3_p1
| eval field_3=field_3_p1+field_1-field_2

The fillnull may be redundant

[mah]

hi,

the result is wrong :

You can see that the field_3 is not correct because it must be LAST field_3+field IN - field OUT

the field_3 here just calculate field IN - field OUT.

example of line 5 : -2 (last field_3)+4-0=2 and not 4

Can we do that ?

[ITWhisperer]

Please share the query you used to get this result

[mah]

I just add your commands after my chart command : 

| chart count(user) over _time by type
| autoregress field_3
| fillnull value=0 field_3_p1
| eval field_3=field_3_p1+IN-OUT

result : 

[ITWhisperer · Accepted solution]

I thought the autoregress would be dynamic - it isn't. Try

| eval change=IN-OUT
| streamstats sum(change) as f3

[mah]

It is perfect ! 

Thank you !