gnuplot.lua

require 'paths'

local torchstyle = [[
##### Modified version of the sample given in
##### http://www.guidolin.net/blog/files/2010/03/gnuplot


set macro

##### Color Palette by Color Scheme Designer
##### Palette URL: http://colorschemedesigner.com/#3K40zsOsOK-K-


 blue_000 = "#A9BDE6" # = rgb(169,189,230)
 blue_025 = "#7297E6" # = rgb(114,151,230)
 blue_050 = "#1D4599" # = rgb(29,69,153)
 blue_075 = "#2F3F60" # = rgb(47,63,96)
 blue_100 = "#031A49" # = rgb(3,26,73)

 green_000 = "#A6EBB5" # = rgb(166,235,181)
 green_025 = "#67EB84" # = rgb(103,235,132)
 green_050 = "#11AD34" # = rgb(17,173,52)
 green_075 = "#2F6C3D" # = rgb(47,108,61)
 green_100 = "#025214" # = rgb(2,82,20)

 red_000 = "#F9B7B0" # = rgb(249,183,176)
 red_025 = "#F97A6D" # = rgb(249,122,109)
 red_050 = "#E62B17" # = rgb(230,43,23)
 red_075 = "#8F463F" # = rgb(143,70,63)
 red_100 = "#6D0D03" # = rgb(109,13,3)

 brown_000 = "#F9E0B0" # = rgb(249,224,176)
 brown_025 = "#F9C96D" # = rgb(249,201,109)
 brown_050 = "#E69F17" # = rgb(230,159,23)
 brown_075 = "#8F743F" # = rgb(143,116,63)
 brown_100 = "#6D4903" # = rgb(109,73,3)

 grid_color = "#d5e0c9"
 text_color = "#222222"

 my_font = "SVBasic Manual, 12"
 my_export_sz = "1024,768"

 my_line_width = "2"
 my_axis_width = "1"
 my_ps = "1"
 my_font_size = "14"

# must convert font fo svg and ps
# set term svg size @my_export_sz fname my_font fsize my_font_size enhanced dynamic rounded
# set term png size @my_export_sz large font my_font
# set term jpeg size @my_export_sz large font my_font
# set term wxt enhanced font my_font

set style data linespoints
set style function lines
set pointsize my_ps

set style line 1 linecolor rgbcolor blue_050 linewidth @my_line_width pt 7
set style line 2 linecolor rgbcolor green_050 linewidth @my_line_width pt 7
set style line 3 linecolor rgbcolor red_050 linewidth @my_line_width pt 7
set style line 4 linecolor rgbcolor brown_050 linewidth @my_line_width pt 7
set style line 5 linecolor rgbcolor blue_025 linewidth @my_line_width pt 5
set style line 6 linecolor rgbcolor green_025 linewidth @my_line_width pt 5
set style line 7 linecolor rgbcolor red_025 linewidth @my_line_width pt 5
set style line 8 linecolor rgbcolor brown_025 linewidth @my_line_width pt 5
set style line 9 linecolor rgbcolor blue_075 linewidth @my_line_width pt 9
set style line 10 linecolor rgbcolor green_075 linewidth @my_line_width pt 9
set style line 11 linecolor rgbcolor red_075 linewidth @my_line_width pt 9
set style line 12 linecolor rgbcolor brown_075 linewidth @my_line_width pt 9
set style line 13 linecolor rgbcolor blue_100 linewidth @my_line_width pt 13
set style line 14 linecolor rgbcolor green_100 linewidth @my_line_width pt 13
set style line 15 linecolor rgbcolor red_100 linewidth @my_line_width pt 13
set style line 16 linecolor rgbcolor brown_100 linewidth @my_line_width pt 13
set style line 17 linecolor rgbcolor "#224499" linewidth @my_line_width pt 11

## plot 1,2,3,4,5,6,7,8,9
set style increment user
set style arrow 1 filled

## used for bar chart borders
## set style fill solid 0.5

set size noratio
set samples 300

set border 31 lw @my_axis_width lc rgb text_color
]]

local _gptable = {}
_gptable.current = nil
_gptable.defaultterm = nil
_gptable.exe = nil
_gptable.hasrefresh = true

local function getexec()
 if not _gptable.exe then
 error('gnuplot executable is not set')
 end
 return _gptable.exe
end

local function findos()
 local s = paths.uname()
 if s and s:match("Windows") then
 return 'windows'
 elseif s and s:match('Darwin') then
 return 'mac'
 elseif s and s:match('Linux') then
 return 'linux'
 elseif s and s:match('FreeBSD') then
 return 'freebsd'
 else
 return '?'
 end
end

local function getfigure(n)
 local n = n
 if not n or n == nil then
 n = #_gptable+1
 end
 if _gptable[n] == nil then
 _gptable[n] = {}
 if _gptable.defaultterm == nil then
 error('Gnuplot terminal is not set')
 end
 local silent = '> /dev/null 2>&1'
 if paths.is_win() then
 silent = '> nul 2>&1'
 end
 _gptable[n].term = _gptable.defaultterm
 _gptable[n].pipe = torch.PipeFile(getexec() .. ' -persist ' .. silent,'w')
 end
 _gptable.current = n
 if not paths.filep(paths.concat(paths.home,'.gnuplot')) then
 _gptable[n].pipe:writeString(torchstyle .. '\n\n\n')
 _gptable[n].pipe:synchronize()
 end
 return _gptable[n]
end

local function gnuplothasterm(term)
 if not _gptable.exe then
 return false--error('gnuplot exe is not found, can not chcek terminal')
 end
 local tfni = os.tmpname()
 local tfno = os.tmpname()
 local fi = io.open(tfni,'w')
 fi:write('set terminal\n\n')
 fi:close()
 os.execute(getexec() .. ' < ' .. tfni .. ' > ' .. tfno .. ' 2>&1 ')
 os.remove(tfni)
 local tf = io.open(tfno,'r')
 local s = tf:read('*l')
 while s do
 if s:match('^.*%s+ '.. term .. ' ') then
 tf:close()
 os.remove(tfno)
 return true
 end
 s = tf:read('*l')
 end
 tf:close()
 os.remove(tfno)
 return false
end

local function findgnuplotversion(exe)
 local ff = io.popen(exe .. ' --version','r')
 local ss = ff:read('*l')
 ff:close()
 local v,vv = ss:match('(%d).(%d)')
 v=tonumber(v)
 vv=tonumber(vv)
 return v,vv
end

local function findgnuplotexe()
 local o = findos()
 local s = paths.findprogram('gnuplot')
 if type(s) == 'string' and s:match(' ') then
 s = '"' .. s .. '"'
 end
 _gptable.hasrefresh = true
 do -- preserve indentation to minimize merging issues
 if s and s:len() > 0 and s:match('gnuplot') then
 local v,vv = findgnuplotversion(s)
 if v < 4 then
 error('gnuplot version 4 is required')
 end
 if v == 4 and vv < 4 then
 -- try to find gnuplot44
 if o == 'linux' and paths.filep('/usr/bin/gnuplot44') then
 local ss = '/usr/bin/gnuplot44'
 v,vv = findgnuplotversion(ss)
 if v == 4 and vv == 4 then
 return ss
 end
 end
 _gptable.hasrefresh = false
 print('Gnuplot package working with reduced functionality.')
 print('Please install gnuplot version >= 4.4.')
 end
 return s
 else
 return nil
 end
 end
end

local function getgnuplotdefaultterm(os)
 if os == 'windows' then
 return 'windows'
 elseif os == 'linux' and gnuplothasterm('wxt') then
 return 'wxt'
 elseif os == 'linux' and gnuplothasterm('qt') then
 return 'qt'
 elseif os == 'linux' and gnuplothasterm('x11') then
 return 'x11'
 elseif os == 'freebsd' and gnuplothasterm('wxt') then
 return 'wxt'
 elseif os == 'freebsd' and gnuplothasterm('qt') then
 return 'qt'
 elseif os == 'freebsd' and gnuplothasterm('x11') then
 return 'x11'
 elseif os == 'mac' and gnuplothasterm('aqua') then
 return 'aqua'
 elseif os == 'mac' and gnuplothasterm('wxt') then
 return 'wxt'
 elseif os == 'mac' and gnuplothasterm('qt') then
 return 'qt'
 elseif os == 'mac' and gnuplothasterm('x11') then
 return 'x11'
 else
 print('Can not find any of the default terminals for ' .. os .. '. ' ..
 'You can manually set terminal by gnuplot.setterm("terminal-name")')
 return nil
 end
end

local function findgnuplot()
 local exe = findgnuplotexe()
 local os = findos()
 if not exe then
 return nil
 end
 _gptable.exe = exe
 _gptable.defaultterm = getgnuplotdefaultterm(os)
end


function gnuplot.setgnuplotexe(exe)
 local oldexe = _gptable.exe

 if not paths.filep(exe) then
 error(exe .. ' does not exist')
 end

 _gptable.exe = exe
 local v,vv = findgnuplotversion(exe)
 if v < 4 then error('gnuplot version 4 is required') end
 if v == 4 and vv < 4 then 
 _gptable.hasrefresh = false
 print('Some functionality like adding title, labels, ... will be disabled, it is better to install gnuplot version 4.4')
 else
 _gptable.hasrefresh = true
 end
 
 local os = findos()
 local term = getgnuplotdefaultterm(os)
 if term == nil then
 print('You have manually set the gnuplot exe and I can not find default terminals, run gnuplot.setterm("terminal-name") to set term type')
 end
end

function gnuplot.setterm(term)
 if gnuplothasterm(term) then
 _gptable.defaultterm = term
 else
 error('gnuplot does not seem to have this term')
 end
end

local function getCurrentPlot()
 if _gptable.current == nil then
 gnuplot.figure()
 end
 return _gptable[_gptable.current]
end

local function writeToPlot(gp,str)
 local pipe = gp.pipe
 pipe:writeString(str .. '\n\n\n')
 pipe:synchronize()
end
local function refreshPlot(gp)
 if gp.fname then
 writeToPlot(gp,'set output "' .. gp.fname .. '"')
 end
 writeToPlot(gp,'refresh')
 if gp.fname then
 writeToPlot(gp,'unset output')
 end
end
local function writeToCurrent(str)
 writeToPlot(getCurrentPlot(),str)
end
local function refreshCurrent()
 refreshPlot(getCurrentPlot())
end

-- t is the arguments for one plot at a time
local function getvars(t)
 local legend = nil
 local x = nil
 local y = nil
 local format = nil

 local function istensor(v)
 return type(v) == 'userdata' and torch.typename(v):sub(-6) == 'Tensor'
 end

 local function isstring(v)
 return type(v) == 'string'
 end

 if #t == 0 then
 error('empty argument list')
 end

 if #t >= 1 then
 if isstring(t[1]) then
 legend = t[1]
 elseif istensor(t[1]) then
 x = t[1]
 else
 error('expecting [string,] tensor [,tensor] [,string]')
 end
 end
 if #t >= 2 then
 if x and isstring(t[2]) then
 format = t[2]
 elseif x and istensor(t[2]) then
 y = t[2]
 elseif legend and istensor(t[2]) then
 x = t[2]
 else
 error('expecting [string,] tensor [,tensor] [,string]')
 end
 end
 if #t >= 3 then
 if legend and x and istensor(t[3]) then
 y = t[3]
 elseif legend and x and isstring(t[3]) then
 format = t[3]
 elseif x and y and isstring(t[3]) then
 format = t[3]
 else
 error('expecting [string,] tensor [,tensor] [,string]')
 end
 end
 if #t == 4 then
 if legend and x and y and isstring(t[4]) then
 format = t[4]
 else
 error('expecting [string,] tensor [,tensor] [,string]')
 end
 end
 legend = legend or ''
 format = format or ''
 if not x then
 error('expecting [string,] tensor [,tensor] [,string]')
 end
 if not y then
 if x:dim() == 2 and x:size(2) == 2 then
 y = x:select(2,2)
 x = x:select(2,1)
 elseif x:dim() == 2 and x:size(2) == 4 and format == 'v' then
 y = torch.Tensor(x:size(1),2)
 xx= torch.Tensor(x:size(1),2)
 y:select(2,1):copy(x:select(2,2))
 y:select(2,2):copy(x:select(2,4))
 xx:select(2,1):copy(x:select(2,1))
 xx:select(2,2):copy(x:select(2,3))
 x = xx
 elseif x:dim() == 2 and x:size(2) > 1 then
 y = x[{ {}, {2,-1} }]
 x = x:select(2,1)
 else
 y = x
 x = torch.range(1,y:size(1))
 end
 end
 if x:dim() ~= 1 and x:dim() ~= 2 then
 error('x and y dims are wrong : x = ' .. x:nDimension() .. 'D y = ' .. y:nDimension() .. 'D')
 end
 if y:size(1) ~= x:size(1) then
 error('x and y dims are wrong : x = ' .. x:nDimension() .. 'D y = ' .. y:nDimension() .. 'D')
 end
 -- if x:dim() ~= y:dim() or x:nDimension() > 2 or y:nDimension() > 2 then
 -- error('x and y dims are wrong : x = ' .. x:nDimension() .. 'D y = ' .. y:nDimension() .. 'D')
 -- end
 -- print(x:size(),y:size())
 return legend,x,y,format
end

-- t is the arguments for one plot at a time
local function getsplotvars(t)
 local legend = nil
 local x = nil
 local y = nil
 local z = nil

 local function istensor(v)
 return type(v) == 'userdata' and torch.typename(v):sub(-6) == 'Tensor'
 end

 local function isstring(v)
 return type(v) == 'string'
 end

 if #t == 0 then
 error('empty argument list')
 end

 if #t >= 1 then
 if isstring(t[1]) then
 legend = t[1]
 elseif istensor(t[1]) then
 x = t[1]
 else
 error('expecting [string,] tensor [,tensor] [,tensor]')
 end
 end
 if #t >= 2 and #t <= 4 then
 if x and istensor(t[2]) and istensor(t[3]) then
 y = t[2]
 z = t[3]
 elseif legend and istensor(t[2]) and istensor(t[3]) and istensor(t[4]) then
 x = t[2]
 y = t[3]
 z = t[4]
 elseif legend and istensor(t[2]) then
 x = t[2]
 else
 error('expecting [string,] tensor [,tensor] [,tensor]')
 end
 elseif #t > 4 then
 error('expecting [string,] tensor [,tensor] [,tensor]')
 end
 legend = legend or ''
 if not x then
 error('expecting [string,] tensor [,tensor] [,tensor]')
 end
 if not z then
 z = x
 x = torch.Tensor(z:size())
 y = torch.Tensor(z:size())
 for i=1,x:size(1) do x:select(1,i):fill(i) end
 for i=1,y:size(2) do y:select(2,i):fill(i) end
 end
 if x:nDimension() ~= 2 or y:nDimension() ~= 2 or z:nDimension() ~= 2 then
 error('x and y and z are expected to be matrices x = ' .. x:nDimension() .. 'D y = ' .. y:nDimension() .. 'D z = '.. z:nDimension() .. 'D' )
 end
 return legend,x,y,z
end

local function getscatter3vars(t)
 local legend = nil
 local x = nil
 local y = nil
 local z = nil

 local function istensor(v)
 return type(v) == 'userdata' and torch.typename(v):sub(-6) == 'Tensor'
 end

 local function isstring(v)
 return type(v) == 'string'
 end

 if #t ~= 3 and #t ~= 4 then
 error('expecting [string,] tensor, tensor, tensor')
 end

 if isstring(t[1]) then
 if #t ~= 4 then
 error('expecting [string,] tensor, tensor, tensor')
 end
 for i = 2, 4 do
 if not istensor(t[i]) then
 error('expecting [string,] tensor, tensor, tensor')
 end
 end
 legend = t[1]
 x = t[2]
 y = t[3]
 z = t[4]
 elseif istensor(t[1]) then
 if #t ~= 3 then
 error('expecting [string,] tensor, tensor, tensor')
 end
 for i = 2, 3 do
 if not istensor(t[i]) then
 error('expecting [string,] tensor, tensor, tensor')
 end
 end
 x = t[1]
 y = t[2]
 z = t[3]
 legend = ''
 else
 error('expecting [string,] tensor, tensor, tensor')
 end
 
 assert(x:dim() == 1 and y:dim() == 1 and z:dim() == 1, 
 'x, y and z must be 1D')
 assert(x:isSameSizeAs(y) and x:isSameSizeAs(z),
 'x, y and z must be the same size')

 return legend, x, y, z
end

local function getimagescvars(t)
 local palette = nil
 local x = nil

 local function istensor(v)
 return type(v) == 'userdata' and torch.typename(v):sub(-6) == 'Tensor'
 end

 local function isstring(v)
 return type(v) == 'string'
 end

 if #t == 0 then
 error('empty argument list')
 end

 if #t >= 1 then
 if istensor(t[1]) then
 x = t[1]
 else
 error('expecting tensor [,string]')
 end
 end
 if #t == 2 then
 if x and isstring(t[2]) then
 palette = t[2]
 else
 error('expecting tensor [,string]' )
 end
 elseif #t > 2 then
 error('expecting tensor [,string]')
 end
 legend = legend or ''
 if not x then
 error('expecting tensor [,string]')
 end
 if not palette then
 palette = 'gray'
 end
 if x:nDimension() ~= 2 then
 error('x is expected to be matrices x = ' .. x:nDimension() .. 'D')
 end
 return x,palette
end

local function gnuplot_string(legend,x,y,format)
 local hstr = 'plot '
 local dstr = {''}
 local coef = {}
 local vecplot = {}
 local function gformat(f,i)
 if f ~= '~' and f:find('~') or f:find('acsplines') then
 coef[i] = f:gsub('~',''):gsub('acsplines','')
 coef[i] = tonumber(coef[i])
 f = 'acsplines'
 end
 if f == '' or f == '' then return ''
 elseif f == '+' or f == 'points' then return 'with points'
 elseif f == '.' or f == 'dots' then return 'with dots'
 elseif f == '-' or f == 'lines' then return 'with lines'
 elseif f == '+-' or f == 'linespoints' then return 'with linespoints' 
 elseif f == '|' or f == 'boxes' then return 'with boxes'
 elseif f == '~' or f == 'csplines' then return 'smooth csplines'
 elseif f == 'acsplines' then return 'smooth acsplines'
 elseif f == 'V' or f == 'v' or f == 'vectors' then vecplot[i]=true;return 'with vectors'
 else return f
 end
 end
 for i=1,#legend do
 if i > 1 then hstr = hstr .. ' , ' end
 hstr = hstr .. " '-' title '" .. legend[i] .. "' " .. gformat(format[i],i)
 end
 hstr = hstr .. '\n'
 for i=1,#legend do
 local xi = x[i]
 local yi = y[i]
 for j=1,xi:size(1) do
 if coef[i] then
 --print(i,coef)
 table.insert(dstr,string.format('%g %g %g\n',xi[j],yi[j],coef[i]))
 elseif vecplot[i] then
 --print(xi,yi)
 table.insert(dstr,string.format('%g %g %g %g\n',xi[j][1],yi[j][1],xi[j][2],yi[j][2]))
 elseif yi:dim() == 1 then
 table.insert(dstr,string.format('%g %g\n',xi[j],yi[j]))
 else
 table.insert(dstr,string.format(string.rep('%g ',1+yi:size(2)) .. '\n',xi[j],unpack(yi[j]:clone():storage():totable())))
 end
 end
 collectgarbage()
 table.insert(dstr,'e\n')
 end
 return hstr,table.concat(dstr)
end
local function gnu_splot_string(legend,x,y,z)
 local hstr = string.format('%s\n','set contour base')
 hstr = string.format('%s%s\n',hstr,'set cntrparam bspline\n')
 hstr = string.format('%s%s\n',hstr,'set cntrparam levels auto\n')
 hstr = string.format('%s%s\n',hstr,'set style data lines\n')
 hstr = string.format('%s%s\n',hstr,'set hidden3d\n')

 hstr = hstr .. 'splot '
 local dstr = {''}
 local coef
 for i=1,#legend do
 if i > 1 then hstr = hstr .. ' , ' end
 hstr = hstr .. " '-'title '" .. legend[i] .. "' " .. 'with lines'
 end
 hstr = hstr .. '\n'
 for i=1,#legend do
 local xi = x[i]
 local yi = y[i]
 local zi = z[i]
 for j=1,xi:size(1) do
 local xij = xi[j]
 local yij = yi[j]
 local zij = zi[j]
 for k=1,xi:size(2) do
 table.insert(dstr, string.format('%g %g %g\n',xij[k],yij[k],zij[k]))
 end
 table.insert(dstr,'\n')
 end
 table.insert(dstr,'e\n')
 end
 return hstr,table.concat(dstr)
end

local function gnu_scatter3_string(legend, x, y, z)
 local hstr = string.format('%s\n','set contour base')
 hstr = string.format('%s%s\n',hstr,'set style data points\n')
 hstr = string.format('%s%s\n',hstr,'set hidden3d\n')

 hstr = hstr .. 'splot '
 local dstr = {''}
 local coef
 for i = 1, #legend do
 if i > 1 then hstr = hstr .. ' , ' end
 hstr = hstr .. " '-'title '" .. legend[i] .. "' " .. 'with points'
 end
 hstr = hstr .. '\n'
 for i = 1, #legend do
 local xi = x[i]
 local yi = y[i]
 local zi = z[i]
 for j = 1, xi:size(1) do
 local xij = xi[j]
 local yij = yi[j]
 local zij = zi[j]
 table.insert(dstr, 
 string.format('%g %g %g\n', xij, yij, zij))
 end
 table.insert(dstr, 'e\n')
 end
 return hstr, table.concat(dstr)
end

local function gnu_imagesc_string(x,palette)
 local hstr = string.format('%s\n','set view map')
 hstr = string.format('%s%s %s\n',hstr,'set palette',palette)
 hstr = string.format('%s%s\n',hstr,'set style data linespoints')
 hstr = string.format('%s%s%g%s\n',hstr,"set xrange [ -0.5 : ",x:size(2)-0.5,"] noreverse nowriteback")
 hstr = string.format('%s%s%g%s\n',hstr,"set yrange [ -0.5 : ",x:size(1)-0.5,"] reverse nowriteback")
 hstr = string.format('%s%s\n',hstr,"splot '-' matrix with image")
 local dstr = {''}
 for i=1,x:size(1) do
 local xi = x[i];
 for j=1,x:size(2) do
 table.insert(dstr,string.format('%g ',xi[j]))
 end
 table.insert(dstr, string.format('\n'))
 end
 table.insert(dstr,string.format('e\ne\n'))
 return hstr,table.concat(dstr)
end

function gnuplot.close(n)
 if not n then
 n = _gptable.current
 end
 local gp = _gptable[n]
 if gp == nil then return end
 if type(n) == 'number' and torch.typename(gp.pipe) == 'torch.PipeFile' then
 _gptable.current = nil
 gnuplot.plotflush(n)
 writeToPlot(gp, 'quit')
 
 -- pipefile:close is buggy in TH
 --gp.pipe:close()
 gp.pipe=nil
 gp = nil
 _gptable[n] = nil
 end
 collectgarbage()
end

function gnuplot.closeall()
 for i,v in pairs(_gptable) do
 gnuplot.close(i)
 end
 _gptable = {}
 collectgarbage()
 findgnuplot()
 _gptable.current = nil
end

local function filefigure(fname,term,n)
 if not _gptable.hasrefresh then
 print('Plotting to files is disabled in gnuplot 4.2, install gnuplot 4.4')
 end

 -- Check whether the output directory can be written to here - torch.PipeFile
 -- has no read/write option so we can't read back any error messages from
 -- gnuplot, and writing to 'non_existent_dir/plot.png' fails silently.
 local outputDir = paths.dirname(fname)
 if outputDir == '' then
 outputDir = '.'
 end
 if not paths.dirp(outputDir) then
 error('cannot save to ' .. fname .. ': directory does not exist')
 end

 local gp = getfigure(n)
 gp.fname = fname
 gp.term = term
 writeToCurrent('set term '.. gp.term)
 --writeToCurrent('set output \'' .. gp.fname .. '\'')
end
function gnuplot.epsfigure(fname,n)
 filefigure(fname,'postscript eps enhanced color',n)
 return _gptable.current
end

function gnuplot.svgfigure(fname,n)
 filefigure(fname,'svg',n)
 return _gptable.current
end

function gnuplot.pngfigure(fname,n)
 local term = gnuplothasterm('pngcairo') and 'pngcairo' or 'png'
 filefigure(fname,term,n)
 return _gptable.current
end

function gnuplot.pdffigure(fname,n)
 local haspdf = gnuplothasterm('pdf') or gnuplothasterm('pdfcairo')
 if not haspdf then
 error('your installation of gnuplot does not have pdf support enabled')
 end
 local term = nil
 if gnuplothasterm('pdfcairo') then
 term = 'pdfcairo enhanced color'
 else
 term = 'pdf enhanced color'
 end
 filefigure(fname,term,n)
 return _gptable.current
end

function gnuplot.figprint(fname)
 local suffix = fname:match('.+%.(.+)')
 local term = nil
 local haspdf = gnuplothasterm('pdf') or gnuplothasterm('pdfcairo')
 if suffix == 'eps' then
 term = 'postscript eps enhanced color'
 elseif suffix == 'png' then
 term = gnuplothasterm('pngcairo') and 'pngcairo' or 'png'
 term = term .. ' size "1024,768"'
 elseif suffix == 'pdf' and haspdf then
 if not haspdf then
 error('your installation of gnuplot does not have pdf support enabled')
 end
 if gnuplothasterm('pdfcairo') then
 term = 'pdfcairo'
 else
 term = 'pdf'
 end
 term = term .. ' enhanced color'
 else
 local errmsg = 'only eps and png'
 if haspdf then
 errmsg = errmsg .. ' and pdf'
 end
 error(errmsg ' for figprint')
 end
 writeToCurrent('set term ' .. term)
 writeToCurrent('set output \''.. fname .. '\'')
 refreshCurrent()
 writeToCurrent('unset output')
 writeToCurrent('set term ' .. _gptable[_gptable.current].term .. ' ' .. _gptable.current .. '\n')
end

function gnuplot.figure(n, config)
 config = config or {}
 local gp = getfigure(n)
 writeToCurrent('set term ' .. _gptable[_gptable.current].term .. ' ' .. _gptable.current .. '\n')
 if not config.noraise then
 writeToCurrent('raise')
 end
 return _gptable.current
end

function gnuplot.plotflush(n)
 if not n then
 n = _gptable.current
 end
 if not n or _gptable[n] == nil then
 print('no figure ' .. tostring(n))
 return
 end
 local gp = _gptable[n]
 --xprint(gp)
 refreshPlot(gp)
 -- if gp.fname then
 -- writeToPlot(gp,'set output "' .. gp.fname .. '"')
 -- writeToPlot(gp,'refresh')
 -- writeToPlot(gp,'unset output')
 -- end
end

local function gnulplot(legend,x,y,format)
 local hdr,data = gnuplot_string(legend,x,y,format)
 writeToCurrent(hdr)
 writeToCurrent(data)
end
local function gnusplot(legend,x,y,z)
 local hdr,data = gnu_splot_string(legend,x,y,z)
 writeToCurrent(hdr)
 writeToCurrent(data)
end
local function gnuscatter3(legend, x, y, z)
 local hdr, data = gnu_scatter3_string(legend, x, y, z)
 writeToCurrent(hdr)
 writeToCurrent(data)
end
local function gnuimagesc(x,palette)
 local hdr,data = gnu_imagesc_string(x,palette)
 writeToCurrent(hdr)
 writeToCurrent(data)
end

function gnuplot.xlabel(label)
 if not _gptable.hasrefresh then
 print('gnuplot.xlabel disabled')
 return
 end
 writeToCurrent('set xlabel "' .. label .. '"')
 refreshCurrent()
end
function gnuplot.ylabel(label)
 if not _gptable.hasrefresh then
 print('gnuplot.ylabel disabled')
 return
 end
 writeToCurrent('set ylabel "' .. label .. '"')
 refreshCurrent()
end
function gnuplot.zlabel(label)
 if not _gptable.hasrefresh then
 print('gnuplot.zlabel disabled')
 return
 end
 writeToCurrent('set zlabel "' .. label .. '"')
 refreshCurrent()
end
function gnuplot.title(label)
 if not _gptable.hasrefresh then
 print('gnuplot.title disabled')
 return
 end
 writeToCurrent('set title "' .. label .. '"')
 refreshCurrent()
end
function gnuplot.grid(toggle)
 if not _gptable.hasrefresh then
 print('gnuplot.grid disabled')
 return
 end
 if toggle then
 writeToCurrent('set grid')
 refreshCurrent()
 else
 writeToCurrent('unset grid')
 refreshCurrent()
 end
end
function gnuplot.logscale(toggle)
 if not _gptable.hasrefresh then
 print('gnuplot.logscale disabled')
 return
 end
 if toggle then
 writeToCurrent('set logscale y')
 refreshCurrent()
 else
 writeToCurrent('unset logscale y')
 refreshCurrent()
 end
end
function gnuplot.movelegend(hloc,vloc)
 if not _gptable.hasrefresh then
 print('gnuplot.movelegend disabled')
 return
 end
 if hloc ~= 'left' and hloc ~= 'right' and hloc ~= 'center' then
 error('horizontal location is unknown : plot.movelegend expects 2 strings as location {left|right|center}{bottom|top|middle}')
 end
 if vloc ~= 'bottom' and vloc ~= 'top' and vloc ~= 'middle' then
 error('horizontal location is unknown : plot.movelegend expects 2 strings as location {left|right|center}{bottom|top|middle}')
 end
 writeToCurrent('set key ' .. hloc .. ' ' .. vloc)
 refreshCurrent()
end

function gnuplot.axis(axis)
 if not _gptable.hasrefresh then
 print('gnuplot.axis disabled')
 return
 end
 if axis == 'auto' then
 writeToCurrent('set size nosquare')
 writeToCurrent('set autoscale')
 refreshCurrent()
 elseif axis == 'image' or axis == 'equal' then
 writeToCurrent('set size ratio -1')
 refreshCurrent()
 elseif axis == 'fill' then
 writeToCurrent('set size ratio 1,1')
 refreshCurrent()
 elseif type(axis) == 'table' then
 if #axis ~= 4 then print('axis should have 4 componets {xmin,xmax,ymin,ymax}'); return end
 writeToCurrent('set xrange [' .. axis[1] .. ':' .. axis[2] .. ']')
 writeToCurrent('set yrange [' .. axis[3] .. ':' .. axis[4] .. ']')
 refreshCurrent()
 end
end

function gnuplot.raw(str)
 writeToCurrent(str)
end

-- plot(x)
-- plot(x,'.'), plot(x,'.-')
-- plot(x,y,'.'), plot(x,y,'.-')
-- plot({x1,y1,'.'},{x2,y2,'.-'})
-- plot({{x1,y1,'.'},{x2,y2,'.-'}})
function gnuplot.plot(...)
 local arg = {...}
 if select('#',...) == 0 then
 error('no inputs, expecting at least a vector')
 end

 local formats = {}
 local xdata = {}
 local ydata = {}
 local legends = {}

 if type(arg[1]) == "table" then
 if type(arg[1][1]) == "table" then
 arg = arg[1]
 end
 for i,v in ipairs(arg) do
 local l,x,y,f = getvars(v)
 legends[#legends+1] = l
 formats[#formats+1] = f
 xdata[#xdata+1] = x
 ydata[#ydata+1] = y
 end
 else
 local l,x,y,f = getvars(arg)
 legends[#legends+1] = l
 formats[#formats+1] = f
 xdata[#xdata+1] = x
 ydata[#ydata+1] = y
 end
 gnulplot(legends,xdata,ydata,formats)
end

-- splot(z)
-- splot({x1,y1,z1},{x2,y2,z2})
-- splot({'name1',x1,y1,z1},{'name2',x2,y2,z2})
function gnuplot.splot(...)
 local arg = {...}
 if select('#',...) == 0 then
 error('no inputs, expecting at least a matrix')
 end

 local xdata = {}
 local ydata = {}
 local zdata = {}
 local legends = {}

 if type(arg[1]) == "table" then
 if type(arg[1][1]) == "table" then
 arg = arg[1]
 end
 for i,v in ipairs(arg) do
 local l,x,y,z = getsplotvars(v)
 legends[#legends+1] = l
 xdata[#xdata+1] = x
 ydata[#ydata+1] = y
 zdata[#zdata+1] = z
 end
 else
 local l,x,y,z = getsplotvars(arg)
 legends[#legends+1] = l
 xdata[#xdata+1] = x
 ydata[#ydata+1] = y
 zdata[#zdata+1] = z
 end
 gnusplot(legends,xdata,ydata,zdata)
end

-- scatter3(x, y, z)
-- scatter3({x1, y1, z1}, {x2, y2, z2})
-- scatter3({'name1', x1, y1, z1}, {'name2', x2, y2, z2})
function gnuplot.scatter3(...)
 local arg = {...}
 if select('#', ...) == 0 then
 error('no inputs, expecting at least a matrix')
 end

 local xdata = {}
 local ydata = {}
 local zdata = {}
 local legends = {}

 if type(arg[1]) == "table" then
 if type(arg[1][1]) == "table" then
 arg = arg[1]
 end
 for i,v in ipairs(arg) do
 local l, x, y, z = getscatter3vars(v)
 legends[#legends + 1] = l
 xdata[#xdata + 1] = x
 ydata[#ydata + 1] = y
 zdata[#zdata + 1] = z
 end
 else
 local l, x, y, z = getscatter3vars(arg)
 legends[#legends + 1] = l
 xdata[#xdata + 1] = x
 ydata[#ydata + 1] = y
 zdata[#zdata + 1] = z
 end
 gnuscatter3(legends, xdata, ydata, zdata)
end

-- imagesc(x) -- x 2D tensor [0 .. 1]
function gnuplot.imagesc(...)
 local arg = {...}
 if select('#',...) == 0 then
 error('no inputs, expecting at least a matrix')
 end
 gnuimagesc(getimagescvars(arg))
end

-- bar(y)
-- bar(x,y)
function gnuplot.bar(...)
 local arg = {...}
 local nargs = {}
 for i = 1,select('#',...) do
 table.insert(nargs,arg[i])
 end
 table.insert(nargs, '|')
 gnuplot.plot(nargs)
end

-- complete function: compute hist and display it
function gnuplot.hist(tensor,bins,min,max)
 local h = gnuplot.histc(tensor,bins,min,max)
 local x_axis = torch.Tensor(#h)
 for i = 1,#h do
 x_axis[i] = h[i].val
 end
 gnuplot.bar(x_axis, h.raw)
 return h
end


findgnuplot()