[R] creating graphs using Rook

[punitha]

hi,

      I m said to display graph in browser using Rook.
So i found a code i.e
library(Rook) # for web functionality 
library(ggplot2) # for graphing 
library(tseries) # used to grab time series from yahoo for stock symbols 
library(plyr) # data tweaks 
 
PIC.DIR = paste(getwd(), 'pic', sep='/') 
 
# define the web page form 
newapp = function(env) { 
    req = Rook::Request$new(env) 
    res = Rook::Response$new() 
 
    if (!is.null(req$POST())) { 
        stock.symbol <- req$POST()[["stock.symbol"]] 
        day.window <- req$POST()[["day.window"]] 
    } else { 
        stock.symbol <- 'AAPL' 
        day.window <- 60 
    } 
    res$write('What stock ticker would you like to see:\n') 
    res$write('<BR/>') 
    res$write('Stock Symbol:\n') 
    res$write('<form method="POST">\n') 
    stock.input <- paste('<input type="text" name="stock.symbol" value="', 
                         stock.symbol, 
                         '">\n', sep='') 
    res$write( stock.input )  
    res$write('<form method="POST">\n') 
    res$write('<input type="radio" name="day.window" value="30">30 Days \n') 
    res$write('<input type="radio" name="day.window" value="60" checked>60
Days \n') 
    res$write('<input type="radio" name="day.window" value="90">90 Days \n') 
    res$write('<input type="submit" name="Go!">\n</form>\n<br>') 
    myNormalize = function (target) { 
        return((target - min(target))/(max(target) - min(target))) 
    } 
 
    if (!is.null(req$POST())) { 
        # get the stock data as a data frame 
        df <-
as.data.frame(get.hist.quote(stock.symbol,start=as.character(Sys.Date() - 
as.numeric(day.window)),quote=c("Open", "High", "Low", "Close"))) 
 
        # add an average and the top/bottom for the candle 
        df <- mutate(df, Average =(High + Low + Close)/3, Bottom =
pmin(Open, Close), Top = pmax(Open, Close), Open.to.Close = ifelse(sign(Open
- Close) == 1,'Increase','Decrease'), Date = row.names(df), Date.Label =
ifelse(weekdays(as.Date(row.names(df))) == 'Friday',row.names(df),'')) #
this gets the date from row.names into a column 
 
        # create a box plot 
        my.plot <- ggplot(data=df, aes(x=Date, lower=Bottom, upper=Top,
middle=Average,  ymin=Low,  ymax=High, color=Open.to.Close,
fill=Open.to.Close), xlab='Date', ylab='Price') + 
            geom_boxplot(stat='identity') + 
            # add the line for average price from HCL 
            geom_line(data=df, aes(x=Date,y=Average, group=0),
color='black') + 
            # tweak the labeling 
            opts(axis.text.x = theme_text(angle=270), legend.position =
'top', legend.direction='horizontal') + 
            scale_x_discrete(labels=df$Date.Label) 
        ggsave(plot=my.plot, paste(PIC.DIR, "/pic", stock.symbol,
day.window, ".png", sep = "")) 
 
        res$write(paste(day.window,' days stock price trend for
',stock.symbol,'<BR/>', sep='')) 
        res$write(paste(" <",  
                        s$full_url("pic"),  
                        > ", sep = "")) 
    } 
    res$finish() 
} 
s = Rhttpd$new() 
s$add(app = newapp, name = "visbin") 
s$add(app = File$new(PIC.DIR), name = "pic") 
s$start() 
s$browse("visbin") 

but when i execute this code i get an error saying
Error in grDevices::png(..., width = width, height = height, res = dpi,  : 
  unable to start png() device

Or Is there any other code which can help me in displaying graph in Rook
using ggplot2





-----
Thank you,

with regards,
Punitha
--
View this message in context: http://r.789695.n4.nabble.com/creating-graphs-using-Rook-tp4643458.html
Sent from the R help mailing list archive at Nabble.com.