comp.lang.idl-pvwave archive: archive » Re: Adding straight lines to a plot

Home » Public Forums » archive » Re: Adding straight lines to a plot

Show: Today's Messages :: Show Polls :: Message Navigator
E-mail to friend

Re: Adding straight lines to a plot [message #73471]

Thu, 11 November 2010 15:22

fgg
Messages: 67
Registered: April 2010

Member

Thanks a lot!

Report message to a moderator

Re: Adding straight lines to a plot [message #73472 is a reply to message #73471]

Thu, 11 November 2010 15:02

David Fanning
Messages: 11724
Registered: August 2001

Senior Member

fgg writes:

>
> Is there a function in IDL to add a straight line through an existing
> plot? Something like the 'abline' function in R, where all you need is
> to specify the y-value for a horizontal line (or the x-value for a
> vertical line).

Here you go.

PRO ABLine, value, $
VERTICAL=vertical, $
LINESTYLE=linestyle, $
THICK=thick, $
COLOR=color

IF N_Elements(color) EQ 0 THEN color = 'white'

IF Keyword_Set(Vertical) THEN BEGIN
PLOTS, [value, value], [!Y.CRange[0], !Y.CRange[1]], $
LINESTYLE=linestyle, THICK=thick, $
COLOR=FSC_Color(String(color))
ENDIF ELSE BEGIN
PLOTS, [!X.CRange[0], !X.CRange[1]], [value, value], $
LINESTYLE=linestyle, THICK=thick, $
COLOR=FSC_Color(color)
ENDELSE

END

Cheers,

David

--
David Fanning, Ph.D.
Fanning Software Consulting, Inc.
Coyote's Guide to IDL Programming: http://www.dfanning.com/
Sepore ma de ni thui. ("Perhaps thou speakest truth.")

Report message to a moderator

Re: Adding straight lines to a plot [message #73473 is a reply to message #73472]

Thu, 11 November 2010 14:38

penteado
Messages: 866
Registered: February 2018

Senior Member
Administrator

On Nov 11, 8:28 pm, fgg <fabioguimaraesgoncal...@gmail.com> wrote:
> Hi,
>
> Is there a function in IDL to add a straight line through an existing
> plot? Something like the 'abline' function in R, where all you need is
> to specify the y-value for a horizontal line (or the x-value for a
> vertical line).
>
> Thanks

The easiest way is to overplot a line. That is, overplot two 2-element
arrays, one with the initial and final x, the other with the initial
and final y.

Report message to a moderator

Re: Adding straight lines to a plot [message #73557 is a reply to message #73472]

Fri, 12 November 2010 06:32

Paul Van Delst[1]
Messages: 1157
Registered: April 2002

Senior Member

David Fanning wrote:
> fgg writes:
>
>> Is there a function in IDL to add a straight line through an existing
>> plot? Something like the 'abline' function in R, where all you need is
>> to specify the y-value for a horizontal line (or the x-value for a
>> vertical line).
>
> Here you go.
>
> PRO ABLine, value, $
> VERTICAL=vertical, $
> LINESTYLE=linestyle, $
> THICK=thick, $
> COLOR=color
>
> IF N_Elements(color) EQ 0 THEN color = 'white'
>
> IF Keyword_Set(Vertical) THEN BEGIN
> PLOTS, [value, value], [!Y.CRange[0], !Y.CRange[1]], $

why not simply
PLOTS, [value, value], !Y.CRange, $

> LINESTYLE=linestyle, THICK=thick, $
> COLOR=FSC_Color(String(color))
> ENDIF ELSE BEGIN
> PLOTS, [!X.CRange[0], !X.CRange[1]], [value, value], $

and similarly
PLOTS, !X.CRange, [value, value], $

?

> LINESTYLE=linestyle, THICK=thick, $
> COLOR=FSC_Color(color)
> ENDELSE
>
> END
>
> Cheers,
>
> David
>
>

Report message to a moderator

Previous Topic:	IDL_IDLBridge limited to 4?
Next Topic:	Adding straight lines to a plot

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

] [

]

Current Time: Wed Oct 08 15:16:06 PDT 2025

Total time taken to generate the page: 0.00686 seconds