Re: [Gretl-users] element-wise matrix operator .<

[artur tarassow]

2012/9/18 Allin Cottrell <cottrell(a)wfu.edu>

> On Tue, 18 Sep 2012, artur tarassow wrote:
>
> > according to the latest changelog it should be possible to use the
> > element-wise matrix operator ".<"
>
> What's new is ".<=" and ".>="; ".<" has been around for a
> while. But anyway...
>
> > I tried this using the latest cvs (Windows), but it does not
> > seem to work, or at least I didn't get the correct syntax. I
> > tried this example
> >
> > matrix A = { 0.6, 1 ; -0.3 , 2 }
> > if A .< 1
> >    print "Hello world"
> > endif
>
> Since ".<" is an element-wise operator, the expression
>
>   A .< 1
>
> produces a matrix result, as you see by doing
>
> <hansl>
> matrix A = { 0.6, 1 ; -0.3 , 2 }
> print A
> Test = A .< 1
> print Test
> </hansl>
>

Of course,  I should have been aware of this.

>
> Such a result cannot be coerced to a boolean value, as
> required by "if". Maybe what you want is
>
> <hansl>
> matrix A = { 0.6, 1 ; -0.3 , 2 }
> if A < 1
>      print "Hello world"
> endif
> </hansl>
>
> (This will not print "Hello world" since the test is for all
> elements less than 1.)
>

Indeed, I was looking for exactly this.

>
> Allin Cottrell
> _______________________________________________
> Gretl-users mailing list
> Gretl-users(a)lists.wfu.edu
> http://lists.wfu.edu/mailman/listinfo/gretl-users
>

Thanks for helping, Allin.
Best,
Artur

2012/9/18 Allin Cottrell <cottr...@wfu.edu>

On Tue, 18 Sep 2012, artur tarassow wrote:

> according to the latest changelog it should be possible to use the
> element-wise matrix operator ".<"

What's new is ".<=" and ".>="; ".<" has been around for a
while. But anyway...

> I tried this using the latest cvs (Windows), but it does not
> seem to work, or at least I didn't get the correct syntax. I
> tried this example
>
> matrix A = { 0.6, 1 ; -0.3 , 2 }
> if A .< 1
>    print "Hello world"
> endif

Since ".<" is an element-wise operator, the _expression_

  A .< 1

produces a matrix result, as you see by doing

<hansl>

matrix A = { 0.6, 1 ; -0.3 , 2 }

print A
Test = A .< 1
print Test
</hansl>

Of course,  I should have been aware of this.

Such a result cannot be coerced to a boolean value, as
required by "if". Maybe what you want is

<hansl>

matrix A = { 0.6, 1 ; -0.3 , 2 }

if A < 1
     print "Hello world"
endif
</hansl>

(This will not print "Hello world" since the test is for all
elements less than 1.)

 

Indeed, I was looking for exactly this.

Allin Cottrell
_______________________________________________
Gretl-users mailing list
gretl-us...@lists.wfu.edu
http://lists.wfu.edu/mailman/listinfo/gretl-users

Thanks for helping, Allin.
Best,
Artur