rename nanonote-example files

nanonote-files/example-files/data/Examples/lua-plplot-examples/x20.lua

@@ -0,0 +1,294 @@
+--[[ $Id: x20.lua 9535 2009-02-17 10:14:04Z smekal $
+
+	plimage demo
+--]]
+
+-- initialise Lua bindings for PLplot examples.
+dofile("plplot_examples.lua")
+
+XDIM = 260
+YDIM = 220
+
+dbg = 0
+nosombrero = 0
+nointeractive = 0
+f_name=""
+
+
+-- Transformation function 
+function mypltr(x,  y)
+  local x0 = (stretch["xmin"] + stretch["xmax"])*0.5
+  local y0 = (stretch["ymin"] + stretch["ymax"])*0.5
+  local dy = (stretch["ymax"]-stretch["ymin"])*0.5
+  local tx = x0 + (x0-x)*(1 - stretch["stretch"]*math.cos((y-y0)/dy*math.pi*0.5))
+  local ty = y
+    
+  return tx, ty
+end
+
+
+-- read image from file in binary ppm format 
+function read_img(fname)
+  -- naive grayscale binary ppm reading. If you know how to, improve it 
+  local fp = io.open(fname, "rb")
+  if fp==nil then
+    return 1
+  end
+
+  -- version
+  local ver = fp:read("*line")
+  
+  if ver~="P5" then -- I only understand this! 
+    fp:close()
+    return 1
+  end
+
+  while fp:read(1)=="#" do
+    local com = fp:read("*line")
+    if com==nil then   
+      fp:close()
+      return 1
+    end
+  end
+  fp:seek("cur", -1)
+  
+  local w, h, num_col = fp:read("*number", "*number", "*number")
+  if w==nil or h==nil or num_col==nil then -- width, height, num colors 
+    fp:close()
+    return 1
+  end
+  
+  -- read the rest of the line (only EOL)
+  fp:read("*line")
+
+  local img = fp:read(w*h)
+  fp:close()
+  if string.len(img)~=(w*h) then
+    return 1
+  end
+
+  local imf = {}
+
+  for i = 1, w do
+    imf[i] = {}
+    for j = 1, h do
+      imf[i][j] = string.byte(img, (h-j)*w+i) -- flip image up-down 
+    end
+  end
+
+  return 0, imf, w, h, num_col
+end
+
+
+-- save plot 
+function save_plot(fname)   
+  local cur_strm = pl.gstrm() -- get current stream 
+  local new_strm = pl.mkstrm() -- create a new one  
+    
+  pl.sdev("psc") -- new device type. Use a known existing driver 
+  pl.sfnam(fname) -- file name 
+
+  pl.cpstrm(cur_strm, 0) -- copy old stream parameters to new stream 
+  pl.replot()	-- do the save 
+  pl.end1() -- close new device 
+
+  pl.sstrm(cur_strm)	-- and return to previous one 
+end
+
+
+--  get selection square interactively 
+function get_clip(xi, xe, yi, ye)
+  return 0, xi, xe, yi, ye
+end
+
+
+-- set gray colormap 
+function gray_cmap(num_col)
+  local r = { 0, 1 }
+  local g = { 0, 1 }
+  local b = { 0, 1 }
+  local pos = { 0, 1 }
+
+  pl.scmap1n(num_col)
+  pl.scmap1l(1, pos, r, g, b)
+end
+
+
+x = {}
+y = {}
+z = {}
+r = {}
+img_f = {}
+cgrid2 = {}
+
+  
+-- Bugs in plimage():
+-- + at high magnifications, the left and right edge are ragged, try
+--   ./x20c -dev xwin -wplt 0.3,0.3,0.6,0.6 -ori 0.5
+     
+-- Bugs in x20c.c:
+-- + if the window is resized after a selection is made on "lena", when
+  --making a new selection the old one will re-appear.
+  
+
+-- Parse and process command line arguments 
+pl.parseopts(arg, pl.PL_PARSE_FULL)
+
+-- Initialize plplot 
+pl.init()
+
+z={}
+
+-- view image border pixels 
+if dbg~=0 then
+  pl.env(1, XDIM, 1, YDIM, 1, 1) -- no plot box 
+  
+  -- build a one pixel square border, for diagnostics 
+  for i = 1, XDIM do
+    z[i] = {}
+    z[i][1] = 1 -- left 
+    z[i][YDIM] = 1 -- right 
+  end
+
+  for i = 1, YDIM do
+    z[1][i] = 1 -- top 
+    z[XDIM][i] = 1 -- botton 
+  end
+
+  pl.lab("...around a blue square."," ","A red border should appear...")
+
+  pl.image(z, 1, XDIM, 1, YDIM, 0, 0, 1, XDIM, 1, YDIM)
+end
+
+-- sombrero-like demo 
+if nosombrero==0 then
+  r = {}
+  pl.col0(2) -- draw a yellow plot box, useful for diagnostics! :( 
+  pl.env(0, 2*math.pi, 0, 3*math.pi, 1, -1)
+
+  for i = 1, XDIM do
+    x[i] = (i-1)*2*math.pi/(XDIM-1)
+  end
+  for i = 1, YDIM do
+    y[i] = (i-1)*3*math.pi/(YDIM-1)
+  end
+
+  for i = 1, XDIM do
+    r[i] = {}
+    z[i] = {}
+    for j=1, YDIM do
+      r[i][j] = math.sqrt(x[i]^2+y[j]^2)+1e-3
+      z[i][j] = math.sin(r[i][j])/r[i][j]
+    end
+  end
+
+  pl.lab("No, an amplitude clipped \"sombrero\"", "", "Saturn?")
+  pl.ptex(2, 2, 3, 4, 0, "Transparent image")
+  pl.image(z, 0, 2*math.pi, 0, 3*math.pi, 0.05, 1, 0, 2*math.pi, 0, 3*math.pi) 
+
+  -- save the plot 
+  if f_name~="" then
+    save_plot(f_name)
+  end
+end
+
+-- read Lena image 
+-- Note we try two different locations to cover the case where this
+-- examples is being run from the test_c.sh script 
+status, img_f, width, height, num_col = read_img("lena.pgm")
+if status~=0 then 
+  status, img_f, width, height, num_col = read_img("../lena.pgm")
+  if status~=0 then 
+    pl.abort("No such file")
+    pl.plend()
+    os.exit()
+  end
+end
+
+-- set gray colormap 
+gray_cmap(num_col)
+
+-- display Lena 
+pl.env(1, width, 1, height, 1, -1)
+
+if nointeractive==0 then
+  pl.lab("Set and drag Button 1 to (re)set selection, Button 2 to finish."," ","Lena...")
+else
+  pl.lab(""," ","Lena...")
+end
+
+pl.image(img_f, 1, width, 1, height, 0, 0, 1, width, 1, height)
+
+-- selection/expansion demo 
+if nointeractive==0 then
+  xi = 200
+  xe = 330
+  yi = 280
+  ye = 220
+
+  status, xi, xe, yi, ye = get_clip(xi, xe, yi, ye)
+  if status~=0 then  -- get selection rectangle 
+    pl.plend()
+    os.exit()
+  end
+
+  pl.spause(0)
+  pl.adv(0)
+
+  -- display selection only 
+  pl.image(img_f, 1, width, 1, height, 0, 0, xi, xe, ye, yi)
+
+  pl.spause(1)
+
+  -- zoom in selection 
+  pl.env(xi, xe, ye, yi, 1, -1)
+  pl.image(img_f, 1, width, 1, height, 0, 0, xi, xe, ye, yi)
+end
+
+-- Base the dynamic range on the image contents. 
+img_max, img_min = pl.MinMax2dGrid(img_f)
+
+-- Draw a saturated version of the original image.  Only use the middle 50%
+-- of the image's full dynamic range. 
+pl.col0(2)
+pl.env(0, width, 0, height, 1, -1)
+pl.lab("", "", "Reduced dynamic range image example")
+pl.imagefr(img_f, 0, width, 0, height, 0, 0, img_min + img_max*0.25, img_max - img_max*0.25)
+
+-- Draw a distorted version of the original image, showing its full dynamic range. 
+pl.env(0, width, 0, height, 1, -1)
+pl.lab("", "", "Distorted image example")
+
+stretch = {}
+stretch["xmin"] = 0
+stretch["xmax"] = width
+stretch["ymin"] = 0
+stretch["ymax"] = height
+stretch["stretch"] = 0.5
+
+-- In C / C++ the following would work, with plimagefr directly calling
+-- mypltr. For compatibilty with other language bindings the same effect
+-- can be achieved by generating the transformed grid first and then
+-- using pltr2. 
+-- pl.imagefr(img_f, width, height, 0., width, 0., height, 0., 0., img_min, img_max, mypltr, (PLPointer) &stretch) 
+
+cgrid2 = {}
+cgrid2["xg"] = {}
+cgrid2["yg"] = {}
+cgrid2["nx"] = width+1
+cgrid2["ny"] = height+1
+
+for i = 1, width+1 do
+  cgrid2["xg"][i] = {}
+  cgrid2["yg"][i] = {}
+  for j = 1, height+1 do
+    xx, yy = mypltr(i, j)
+    cgrid2["xg"][i][j] = xx
+    cgrid2["yg"][i][j] = yy
+  end
+end
+    
+--pl.imagefr(img_f, 0, width, 0, height, 0, 0, img_min, img_max, "pltr2", cgrid2)
+pl.imagefr(img_f, 0, width, 0, height, 0, 0, img_min, img_max, "mypltr")
+
+pl.plend()