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Number of observations in alpha series

Posted: Mon Sep 01, 2014 7:14 am
by ErikG
Hi,

I'm trying to get the number of observations in an alpha series but I keep getting the error message: Alpha sent to function which operates on a matrix:


WfCreate(wf=unstruct, page=test) u 10
Alpha aAlphaSeries = "A"
!iK = @Last(aAlphaSeries)
!iK = @Obs(aAlphaSeries)

/Erik.

Re: Number of observations in alpha series

Posted: Tue Sep 02, 2014 8:11 am
by EViews Gareth
Try alpha.@first or alpha.@last

Re: Number of observations in alpha series

Posted: Wed Sep 03, 2014 4:46 am
by ErikG
Hi,

It works but I must say the code could be improved.... I have an alpha series called "a" with 21 observations of which the 21st is empty/missing.

a.@first returns the string 21 - I would expect a string with the first observation
a.@last returns the string 20 - I would expect a string with the last observation, or an integer containing the index of the last non-missing observation
a.@obs returns 0 - I would like it to return the number of non-missing observations.

I am working in an unstructured/undated workfile, I guess it might work differently in a dated workfile.

/Erik.

Re: Number of observations in alpha series

Posted: Wed Sep 03, 2014 12:10 pm
by EViews Gareth
I can't replicate this. Could you post an example?

Re: Number of observations in alpha series

Posted: Thu Sep 04, 2014 3:36 am
by ErikG
Neither can I it seems for the @first function! I'm slightly confused now because I'm pretty sure it returned 21, but I guess I was mistaken.

Nevertheless @obs returns zero - as in the example below, but that's not a big problem, I'll just avoid that function when dealing with alphas.

Code: Select all

WfCreate(wf=unstruct, page=test)  u 5

Alpha a
a(1) = "C"
a(2) = "D"
a(3) = "E"
a(4) = "F"


!obs = a.@obs
@UiPrompt(@Str(!obs))

Re: Number of observations in alpha series

Posted: Fri Sep 05, 2014 5:46 am
by ErikG
Hi again,

It would be nice if the @obs function did work, since @last will not give a currect number of non-missing observations if the alpha series has 'holes' in it.

/Erik.

Re: Number of observations in alpha series

Posted: Fri Sep 05, 2014 8:29 am
by EViews Gareth
I'll see that it gets added for the next version.

Re: Number of observations in alpha series

Posted: Fri Sep 05, 2014 9:17 am
by EViews Gareth
ok, I added support for the @obs data member on alpha series into EViews 8. Next patch should have it.

I'll also add support for the @obs() function for EViews 9.

Re: Number of observations in alpha series

Posted: Mon Sep 08, 2014 12:21 am
by ErikG
Great, thanks!

Re: Number of observations in alpha series

Posted: Thu Jun 15, 2017 6:20 pm
by bcchen
Hi,

One follow up question that is related: How do I store the number of observations of a alpha series as a series?

I tried:

series count=alpha.@obs

but the count shows all 0.

Any idea?

Thanks,
BC

Re: Number of observations in alpha series

Posted: Thu Jun 15, 2017 9:33 pm
by EViews Gareth

Code: Select all

create u 100
smpl if nrnd<1.5
alpha a = "hello world"
smpl @all

series count = a.@obs
show count