root / barchart / trunk / barchart.py

#! /usr/local/bin/python
##################################################
# Name:        barchart - Python BarCharts in SVG
# Author:      Philip J Cooper <Philip.Cooper@openvest.org>
# Start date:  18 July 2003
# Current Date:20 Feb 2006
# Purpose:     Get prices from ovpyq and produce an SVG Chart
# version Note:This uses ovpyq and is thus dynamic in how it
#              updates as it queries.  
##############################################################

__version__ = "0.4.0"

import sys,cgi
import ovpyq, mx.DateTime

if len(sys.argv)>1:
    ticker=sys.argv[1]
else:
    try:
        query = cgi.FieldStorage()
        if query.has_key("tick"):
            ticker= query["tick"].value
        else:
            ticker= query["field_ticker"].value
    except KeyError:
        ticker = "RHT"
    

## get the Name for the Ticker
name=ovpyq.getName(ticker)

## Get the History for the Ticker
ndays=365
enddt=mx.DateTime.today()
begdt=enddt-ndays
hist=ovpyq.getCachedTicker(enddt-ndays,enddt,ticker)

################################################################

color="blue"
w=800.0       #this should be a float not an int
h=600.0       #this should be a float not an int 
cw=w-100
ch=h-100

################################################################################
## begin the header
print "Content-type: image/svg+xml"
print ""

print """<?xml version="1.0"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"
          "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
"""

################################################################################
## set the coordinates/size
print '<svg  xmlns="http://www.w3.org/2000/svg"'
print '      xmlns:xlink="http://www.w3.org/1999/xlink"'
print '       viewBox="0 0 %i %i">'%(w,h)

################################################################################
## add static filters and defs 
print """
<title>barchart.svg</title> 
<desc>line graph</desc>
  <defs>
    <filter id="DropShadowFilter" filterUnits="objectBoundingBox" x="-10%" y="-10%" width="120%" height="120%">
      <feGaussianBlur in="SourceAlpha" stdDeviation="2" result="BlurAlpha"/>
      <feOffset in="BlurAlpha" dx="4" dy="4" result="OffsetBlurAlpha"/>
      <feMerge>
        <feMergeNode in="OffsetBlurAlpha"/>
        <feMergeNode in="SourceGraphic"/>
      </feMerge>
    </filter>
  </defs>
"""
################################################################################
## start the chart
print '<g id="chart" transform="translate(%i, %i)" style="filter:url(#DropShadowFilter)">'%(50,50+ch)

################################################################################
## add the company name
print '<text id="Company" x="50" y="-%i" font-size="30" style=";font-weight:Normal;text-anchor:left;stroke:%s;fill:%s"  >%s</text>'%(ch+10,color,color,name)


################################################################################
## add the x and y axis
print '<path d="M0,0H-5 0 V 5 -%i h -5 10 -5 V 0 H%i V 5 -5 0 H 0" style="fill:none;stroke:black"/>'%(ch,cw)

################################################################################
## lets do the x ticks labels and grid
mth=['','Jan','Feb','Mar','Apr','May','Jun','Jul','Aug','Sep','Oct','Nov','Dec']
stepx=1.0*cw/len(hist)
x=stepx/2
months=[a[0].month for a in hist]   #months=map(lambda x:x[1].month,hist)
begx=x; begm=months[0]
for m in months:
    x=x+stepx
    if m <> begm:
        print '<path style="fill:none;stroke:grey" d="M %i 0 v-%i"/>'%(x,ch)
        print '<text x="%i" y="15" style="font-size:15;text-anchor:middle">%s</text>'%((begx+x)/2,mth[begm])
        begx=x; begm=m
        #begx+x/2,mth
print '<text x="%i" y="15" style="font-size:15;text-anchor:middle">%s</text>'%((begx+x)/2,mth[begm])        

################################################################################
## lets do the y ticks labels and grid
maxgrid=5
intervals=(.1,.25,.5,1,2,5,10,25,50,100)     #.5 was here but didn't work in arg3 to range
hi=max([x[2] for x in hist]) 
lo=min([x[3] for x in hist]) 
for ystep in intervals:
    y=(hi-lo)/ystep
    if ( y <= maxgrid):
       break;            #we've found one that works so stop iterating 
#  This is to get the tick marks
#  a lot of rounding and stuff
#  I'm sure there's a simpler better way to do this
#  but my head hurts so I'll stop now
lotic=int((lo+ystep)/ystep)*ystep
hitic=int((hi+ystep)/ystep)*ystep
y=[i*ystep+lotic for i in range((hitic-lotic)/ystep)]

#  draw the lines
print '      <path  id="ygrid" style="fill:none;stroke:grey" d=" '
for g in y:
  print 'M0,-%i h%i '%((g-lo)*ch/(hi-lo),cw),
print '"/>'
#  add the labels
for g in y:
    print '<text x="-20" y="-%i" style="font-size:15;text-anchor:middle">%0.2f</text>'%((g-lo)*ch/(hi-lo),g)

################################################################################
## now lets do the actual bars
xstep=1.0*cw/len(hist)
x=0.0
print '<path  id="chartbars" style="fill:none;stroke:%s"  d="'%color
for b in hist:
    x=x+xstep
    b=map(lambda yy:(float(yy)-lo)*ch/(hi-lo),b[1:5])
    print  'M %s,-%i h%s V-%i -%i -%i h%s '%(x,b[0],xstep/2,b[1],b[2],b[3],xstep/2),
print '"/>'
################################################################################
print "</g></svg>"