* A Grads script to draw legends for line plots having line and marker
*
*TTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTT 
* Author : Martin V. Mathew, Indian Institute of Technology Kharagpur  
* Prepared on: 26 September 2011
* Last modified on :31 July 2013
* Please report bugs in following email: vmartinmathew@gmail.com
*LLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLL
*
function legend_lin_mkr(args)
* args = strtXpstn strtYpstn mkrStyl LnStyl txt
 
if (args='')
    say 'Apparent error in use of script legend_lin_mkr.gs'
usage()
return
endif

if (arg='-h')
usage()
return
endif

strtXpstn=subwrd(args,1)
strtYpstn=subwrd(args,2)
mkrStyl=subwrd(args,3)
LnStyl=subwrd(args,4)
clr=subwrd(args,5)
txt=subwrd(args,6)
txtclrIn=subwrd(args,7)
mkrSz=subwrd(args,8)
txtSz=subwrd(args,9)

if (strtXpstn >1)
say ' Error x-position given is outside the limit [0 - 1]'
say ' Input argument currently entered is:  'strtXpstn
usage()
return
endif

if (strtYpstn >1)
say ' Error y-position given is outside the limit [0 - 1]'
say ' Input argument currently entered is: 'strtYpstn
usage()
return
endif

if (mkrStyl<0|mkrStyl>11)
say ' Number indicating marker type, is outside the limit [0 11]'
say ' Input argument currently entered is:  'mkrStyl
usage()
return
endif

if (LnStyl<0|LnStyl>7)
say ' Number indicating Line style, is outside the limit [0 7]'
say ' Input argument currently entered is:  'LnStyl
usage()
return
endif

if (clr<0|clr>15)
say ' Number indicating color for line and marker , is outside the limit [1 15]'
say ' Input argument currently entered is: 'clr
usage()
return
endif

if (txtclrIn<0|txtclrIn>15)
say ' Number indicating color for line and marker , is outside the limit [1 15]'
say ' Input argument currently entered is: 'txtclrIn
usage()
return
endif

if (txtclrIn= '' )
txtclr=1
else
txtclr=txtclrIn
endif

if (mkrSz= '' )
mkrSize=0.07
else
mkrSize=mkrSz
endif

if (txtSz= '' )
TextSiz=0.1
else 
TextSiz=txtSz
endif

* ---------------------------------------------------

'q gxinfo'
xref=subwrd(result,14)
yref=subwrd(result,20)
x2=subwrd(result,16)
y2=subwrd(result,22)
xpstn=xref+(x2-xref)*strtXpstn
ypstn=yref+(y2-yref)*strtYpstn
lengt=0.35;* Length  of the legend line
spc=0.07;* Space between legend line and assoiated text
xEndPstn=xpstn+lengt
xTxtStrt=xEndPstn+spc

* ---------------------------------------------------
* Drawing legend
* ---------------------------------------------------
'set line 'clr' 'LnStyl;*set line color# <style> <thickness>
'draw line 'xpstn' 'ypstn' 'xEndPstn' 'ypstn
'draw mark 'mkrStyl' 'xpstn' 'ypstn' 'mkrSize
'draw mark 'mkrStyl' 'xEndPstn' 'ypstn' 'mkrSize
'set string 'txtclr' l 1 0';*set string color <justification <thickness <rotation>>>
'set strsiz 'TextSiz' 'TextSiz
'draw string 'xTxtStrt' 'ypstn' 'txt

return

function usage()
*
* Print usage information.
*
say 'Script to draw legends for line plots having line and marker'
say ''
say 'Usage run legend_lin_mkr strtXpstn strtYpstn mkrStyl LnStyl clr txt <txtClr> <mkrSz> <txtSz>'
say 'Mandatory Arguments:'
say '         strtXpstn   Starting x position of the legend, it should be given'   
say '                     in a scale of 0-1 starting from left side of subplot '
say '         strtYpstn   Starting y position of the legend it should be given'   
say '                     in a scale of 0-1 starting from bottom of subplot '
say '         mkrStyl     Number indicating marker type, numbers of marker types'
say '                     follow that of command "set cmark marktype"'
say '         LnStyl      Number indicating line style, numbers of line style'
say '                     follow that of command "set cstyle style"'
say '         clr         Number indicating colour for both marker and line. It'
say '                     is assumed that both the line and marker have same color'
say '         txt         a short string that identifies what the line is intended'
say '                     to represent. Please avoid space within this string.'
say 'Optional Arguments:'
say '         <txtClr>    Color in which text is to be written if no color is '
say '                     black is used as the default color' 
say '         <mkrSz>     Size of the marker on legend, if no size is specified'      
say '                     a default size of 0.07 is used'  
say '         <txtSz>     Specifies size of the text on the legend, If no size is' 
say '                     specified, a default value of 0.1 is used'

return