查看“IDL8中的plot函数”的源代码

==基本图形==
p = PLOT(data, '-r2+')
 ；Tokens in the Format string represent values of the LINESTYLE, COLOR, THICK, and SYMBOL properties. 

*linestyle 
 0, '-',solid
 1,':',dotted
 2,'--',dashed
 3,'-.',dash_dot

*axes
 p  = PLOT(/TEST)
 ax = p.AXES
 ax[0].TITLE = 'X axis'
 ax[1].TITLE = 'Y axis'
 ax[2].HIDE = 1 ; hide top X axis
 ax[3].HIDE = 1 ; hide right Y axis
 ax[0].showtext=0 ;隐藏坐标上的数字和title，画多个panel的紧凑直方图很有用（见下一小节）

==多个panel==
*画多个panel的时候可以用layout关键词,而且可以动态调整
  fn = exp(SIN(FINDGEN(100))^FINDGEN(100))
  w1 = WINDOW()
  p1 = PLOT(fn, LAYOUT = [1, 2, 1], /CURRENT, TITLE = '1')
  p2 = PLOT(fn, LAYOUT = [2, 2, 3], xrange=[25, 42], /CURRENT, TITLE = '2')
  p3 = PLOT(fn, LAYOUT = [2, 2, 4], xrange=[50, 60], /CURRENT, TITLE = '3')
*也可以用position来自定义

==图形操作==
*选择图形
 P1=plot(/test,layout=[1,2,1])
 P2=plot(/test,layout=[1,2,2],/current)
 P1.select

*删除图形元素
:P2.delete

*生成图形的code [http://www.harrisgeospatial.com/docs/generatecode.html]
:p.GenerateCode, 'mycode.pro' 


*save
:可以直接把图保存成文件
  p = OBJARR(3)
  ; Create three plots with random data
  FOR i = 0, 2 DO BEGIN
   t = 0.1*FINDGEN(50)
   y = SMOOTH(RANDOMU(seed,50), 5)
   p[i] = PLOT(t,y,'b', SYMBOL='D', TITLE='Observation'+STRING(i+1))
  ENDFOR
 ; Build the multi-page PDF file, one page at a time
  p[0].Save, 'data1.pdf', /APPEND
  p[1].Save, 'data1.pdf', /APPEND
  p[2].Save, 'data1.pdf', /APPEND, /CLOSE