[R] computing on expressions

[Vadim Organovich]

Thanks!

Here is a less verbose variation based on suggestion by Phil Spector:

parse(text=paste(expression(a>0), "& b>0"))

________________________________________
From: Henrique Dallazuanna [wwwhsd at gmail.com]
Sent: Friday, October 03, 2008 11:08 AM
To: Vadim Organovich
Cc: r-help at r-project.org
Subject: Re: [R] computing on expressions

Try this:

parse(text = paste(capture.output(expr[[1]]), " & b > 0"))

On Fri, Oct 3, 2008 at 12:48 PM, Vadim Organovich
<vogranovich at jumptrading.com> wrote:
> Dear R-users,
>
> Suppose I have an expression:
>
> expr = expression(a>0)
>
> and now I want to modify it to expression(a>0 & b>0). The following doesn't work:
>
> expr = expression(expr & b>0)
>
> What would be a good way of doing this?
>
> Thanks,
> Vadim
>
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--
Henrique Dallazuanna
Curitiba-Paraná-Brasil
25° 25' 40" S 49° 16' 22" O

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