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Re: Plotting a horizontal line over a cgImage [message #93659 is a reply to message #93654]

Fri, 23 September 2016 12:04

Christina Haig
Messages: 4
Registered: August 2016

Junior Member

On Thursday, September 22, 2016 at 5:08:47 PM UTC-4, Jeremy Bailin wrote:
> On Monday, August 29, 2016 at 11:03:11 AM UTC-5, Christina Haig wrote:
>> This question probably has a very specific audience, but anyone who might be able to help me I would greatly appreciate.
>>
>> Here is a good example of a cgimage plot, somewhat complex, but nothing untoward:
>>
>> p = pos[*,0]
>> cgimage,data1,/DEVICE,/SCALE,/AXES,position=[p[0],p[1],p[2], p[3]],$
>> xrange=[mint,maxt],yrange=[minp,maxp],charsize=3,$
>> AXKEYWORDS={xtickformat:'(A1)',ylog:1,yticks:2,$
>> ytickname:['10!e0','10!e1','10!e2']},/noerase
>>
>> As you can see, the yrange goes roughly from 1 to 100ish. I would like to plot a horizontal line at 2 that references the axes set in the cgimage command, and at the position of the same (there are 12 total plots in my output). Now oplot obviously does not allow the position command. So I attempted to cleverly use the cgplot command to overplot the line.
>>
>> cgplot,[mint,maxt],[2.0,2.0],thick=4,line=5,color=255,$
>> position=[p[0],p[1],p[2],p[3]],/overplot
>>
>> However nothing shows up in my plot. Can anyone advise me how I might solve this problem?
>>
>> Thanks,
>> Christina
>
> Are minp and maxp what you think they are?
>
> -Jeremy.

Apologies for the delay in replying. This was in fact the problem. The problem was my data was already logarithmic, and thus my axes were 0 - 2.0. My fault for not remembering that /ylog just changes the tick names of the axes on cgplot, but the min and max has to be already logged.

So what I needed was to put in log(2.0), instead of just 2.0. I'll leave this thread up in case other people have trouble with logarithmic cgplot.

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[Message index]

		Plotting a horizontal line over a cgImage By: Christina Haig on Mon, 29 August 2016 09:03
		Re: Plotting a horizontal line over a cgImage By: wlandsman on Mon, 29 August 2016 11:20
		Re: Plotting a horizontal line over a cgImage By: Christina Haig on Mon, 29 August 2016 12:29
		Re: Plotting a horizontal line over a cgImage By: wlandsman on Tue, 30 August 2016 06:59
		Re: Plotting a horizontal line over a cgImage By: Christina Haig on Mon, 29 August 2016 11:20
		Re: Plotting a horizontal line over a cgImage By: Jeremy Bailin on Thu, 22 September 2016 14:08
		Re: Plotting a horizontal line over a cgImage By: Christina Haig on Fri, 23 September 2016 12:04

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