Messages from Usenet group comp.lang.idl-pvwave, compiled by Paulo Penteado
here is a example data = DIST(500) x = FINDGEN(500, start=1) win = window() win.refresh, /disable i = image(data, x, x, /current, /axis) win.save, 'test.png' "test.png" file No image appears.!!(just axes)-> bug?? and question. data = DIST(500) x = FINDGEN(500, start=1)/5 c = contour(data, x, x, /ylog) i = image(data, x, x, /ylog, /axis) image function does not appear to ylog.(just yaxis value.....) but contour function is OK. Is that intended?? idl 8.4 and 8.3
the first is easy. take away: win.refresh, /disable Cheers, Helder On Wednesday, February 11, 2015 at 2:53:08 AM UTC+1, Dae-Kyu Shin wrote: > here is a example > > data = DIST(500) > x = FINDGEN(500, start=1) > win = window() > win.refresh, /disable > i = image(data, x, x, /current, /axis) > win.save, 'test.png' > > "test.png" file No image appears.!!(just axes)-> bug?? > > > > > and question. > > data = DIST(500) > x = FINDGEN(500, start=1)/5 > > c = contour(data, x, x, /ylog) > i = image(data, x, x, /ylog, /axis) > > image function does not appear to ylog.(just yaxis value.....) > but contour function is OK. > Is that intended?? > > > > idl 8.4 and 8.3
On 11.02.2015 02:53, Dae-Kyu Shin wrote: > image function does not appear to ylog. > but contour function is OK. > Is that intended?? I think it is intended, or rather it is impossible for image() to know exactly what to do with your image. Stretching an image and changing its pixel resolution is a quite intrusive behavior, so that if you really want to stretch an image you should decide the "how" by yourself.
On Wednesday, February 11, 2015 at 8:22:27 AM UTC-7, Fabien wrote: > On 11.02.2015 02:53, Dae-Kyu Shin wrote: >> image function does not appear to ylog. >> but contour function is OK. >> Is that intended?? > > I think it is intended, or rather it is impossible for image() to know > exactly what to do with your image. Stretching an image and changing its > pixel resolution is a quite intrusive behavior, so that if you really > want to stretch an image you should decide the "how" by yourself. Hi all, Fabien is correct - Image does not work with log axes - it would be weird (although possible) to stretch each pixel by a different "logarithmic" amount. So you either need to do the stretch manually... or perhaps better, you should take the log of your "y" axis values and do the contour plot without the log keyword. And Helder's correct about the other one - if you do /disable, you had better do an /enable before trying to output. Cheers, Chris