diff alignr.py @ 11:b7f1d9f8f3bc

Uploaded

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/alignr.py	Sat Mar 10 07:59:27 2012 -0500
@@ -0,0 +1,353 @@
+'''
+the scripts takes two files as input, and compute the coverage of 
+features in input 1 across features in input 2. Features in input 2 are 
+divided into bins and coverage is computed for each bin.  
+
+please check the help information by typing:
+
+    python align.py -h
+
+
+requirement:
+    please install the following tools first:
+    bedtools:   for read/region overlapping, http://code.google.com/p/bedtools/
+    
+'''
+
+import os,sys,os.path
+from optparse import OptionParser
+
+def lineCount(filename):
+    with open(filename) as f:
+        for i, l in enumerate(f):
+            pass
+    return i + 1
+
+def combineFilename(f1,f2):
+    '''
+    fuse two file names into one
+    '''
+    return f1.split('/')[-1]+'-'+f2.split('/')[-1]
+
+def checkFormat(filename1,filename2,input1format):
+    '''
+    check the format of input files
+    '''
+
+    # file1
+    # read the first line, see how many filds
+    ncol1 = 6
+    if input1format == "BED":
+        f = open(filename1)
+        line = f.readline().strip().split('\t')
+        ncol1 = len(line)
+        if ncol1 < 3:
+            print "ERROR: "+filename1+" has only "+str(ncol1)+" columns (>=3 required). Make sure it has NO header line and is TAB-delimited."
+            sys.exit(1)
+        f.close()
+     
+    # file2
+    f = open(filename2)
+    line = f.readline().strip().split('\t')
+    ncol2 = len(line)  
+    if ncol2 < 3:
+        print "ERROR: "+filename2+" has only "+str(ncol2)+" columns (>=3 required). Make sure it has NO header line and is TAB-delimited."
+        sys.exit(1)        
+
+    return ncol1,ncol2
+
+
+def makeBed(filename,ncol):
+    '''
+    add up to 6 column
+    '''
+    f = open(filename)
+    outfile = filename+'.tmp.bed'
+    outf = open(outfile,'w')
+    if ncol == 3:
+        for line in f:
+            outf.write(line.strip()+'\t.\t0\t+\n')
+    elif ncol == 4:
+        for line in f:
+            outf.write(line.strip()+'\t0\t+\n')
+    if ncol == 5:
+        for line in f:
+            outf.write(line.strip()+'\t+\n')
+    f.close()
+    outf.close()
+    return outfile
+    
+def makeWindow(filename,window):
+
+    outfile = filename+'-window='+str(window)+'.tmp.bed'
+    if not os.path.exists(outfile):
+        f=open(filename)
+        out = open(outfile,'w')
+        lines = f.readlines()
+        if 'track' in lines[0]:
+            del lines[0]
+        for line in lines:
+            flds = line.strip().split('\t')
+
+            #new position
+            center = (int(flds[1]) + int(flds[2]))/2
+            start = center - window
+            end = center + window
+            if start >= 0:
+                flds[1] = str(start)
+                flds[2] = str(end)
+                out.write('\t'.join(flds)+'\n')
+        f.close()
+        out.close()
+    return outfile
+
+def groupReadsMapped2aRegion(filename,ncol):
+    '''
+    read output from intersectBED
+    find all reads mapped to each region
+    '''
+    try:
+        f=open(filename)
+        #If filename cannot be opened, print an error message and exit
+    except IOError:
+        print "could not open",filename,"Are you sure this file exists?"
+        sys.exit(1)
+    lines = f.readlines()
+    
+    allReadsStart = {}
+    allReadsEnd = {}
+    regionStrand = {}
+    regionStart = {}
+    regionEnd = {}
+    
+    for line in lines:
+        flds = line.strip().split('\t')
+        key = '_'.join(flds[ncol:(ncol+4)])
+        if not allReadsStart.has_key(key):
+            allReadsStart[key] = list()
+            allReadsEnd[key] = list()
+        #print flds[ncol+0],flds[ncol+1],flds[ncol+2]
+        allReadsStart[key].append(int(flds[1]))
+        allReadsEnd[key].append(int(flds[2]))
+        regionStrand[key] = flds[ncol+5]  
+        regionStart[key] = int(flds[ncol+1])    
+        regionEnd[key] = int(flds[ncol+2])      
+    return (allReadsStart,allReadsEnd,regionStrand,regionStart,regionEnd)
+            
+            
+def createRegionProfile(allReadsStart,allReadsEnd,regionStrand,regionStart,regionEnd,nbins):
+    '''
+    each region is divided into nbins
+    compute the number of reads covering each bin for each region 
+    '''
+    RegionProfile = {}
+    nRead = {}  # num of all reads in the region
+    for region in allReadsStart.keys():
+        RegionProfile[region] = [0]*nbins
+        nRead[region] = len(allReadsStart[region])
+        #print region,nRead[region],allReadsStart[region]
+        for i in range(nRead[region]):
+            RegionProfile[region] = updateRegionCount(RegionProfile[region],allReadsStart[region][i],allReadsEnd[region][i],regionStart[region],regionEnd[region],regionStrand[region],nbins)
+    return RegionProfile,nRead
+    
+def updateRegionCount(RegionCount,readStart,readEnd,regionStart,regionEnd,strand,nbins):
+    '''
+    each region is divided into nbins,
+    add 1 to each bin covered by the read  
+    '''
+    L = regionEnd-regionStart
+    start = int(nbins*(readStart-regionStart)/L)
+    end = int(nbins*(readEnd-regionStart)/L)
+    if start < 0:
+        start = 0
+    if end > nbins:
+        end = nbins
+    if strand == '-':        
+        for i in range(start,end):
+            RegionCount[nbins-1-i] = RegionCount[nbins-1-i] + 1
+    else: # if the 6th column of the input is not strand, will treat as + strand by default       
+        for i in range(start,end):
+            RegionCount[i] = RegionCount[i] + 1            
+    return RegionCount
+
+def saveProfile(filename,Profile,nRegion):
+    out = open(filename,'w')
+    for regionType in Profile.keys():
+        #print Profile[regionType]
+        out.write(regionType+'\t'+str(nRegion[regionType])+'\t'+'\t'.join(map(str,Profile[regionType]))+'\n')    
+                    
+def saveSummary(filename,Profile,nbin):
+    out = open(filename+'.summary','w')
+
+    nfeat = len(Profile)
+    summaryprofile = [0]*nbin
+    for regionType in Profile.keys():
+        for i in range(nbin):
+            summaryprofile[i] += Profile[regionType][i]    
+    out.write(filename+'\t'+str(nfeat)+'\t'+'\t'.join(map(str,summaryprofile))+'\n')  
+    out.close()
+    # calculate standard error
+    out = open(filename+'.standarderror','w')
+    sd = [0.0]*nbin
+    u = [0.0]*nbin 
+    for i in range(nbin):
+        u[i] = float(summaryprofile[i])/nfeat
+        for regionType in Profile.keys():
+            sd[i] = sd[i] + (Profile[regionType][i] - u[i])**2
+        sd[i] = sd[i]**0.5 / nfeat
+    out.write(filename+'\t'+str(nfeat)+'\t'+'\t'.join(map(str,sd))+'\n')  
+    out.close()    
+                
+def main():
+    usage = "usage: %prog [options] -a inputA -b inputB"
+    parser = OptionParser(usage)
+    parser.add_option("-a", dest="inputA",
+                      help="(required) input file A, interval (first 3 columns are chrN, start and end) or BAM format. The script computes the depth of coverage of features in file A across the features in file B" )                                                
+    parser.add_option("-b",dest="inputB",
+                      help="(required) input file B, interval file" )                                                
+    parser.add_option("-f",dest="aformat",default="BED",
+                      help="Format of input file A. Can be BED (default) or BAM")
+    parser.add_option("-w",type='int',dest="window",
+                      help="Generate new inputB by making a window of 2 x WINDOW bp (in total) flanking the center of each input feature" )     
+    parser.add_option("-n", type="int", dest="nbins",default=100,
+                        help="number of bins. Features in B are binned, and the coverage is computed for each bin. Default is 100")                    
+    parser.add_option("-s",action="store_true", dest="strandness",
+                      help="enforce strandness: require overlapping on the same strand. Default is off")
+    parser.add_option("-p",action="store_true", dest="plot",default=False,
+                      help="load existed intersectBed outputfile")
+    parser.add_option("-q", action="store_true", dest="quiet",default=False,
+                        help="suppress output on screen")
+    parser.add_option("-o", dest="output_data",
+                      help="(optional) output coverage file (txt) name." )
+    parser.add_option("-v", dest="output_plot",
+                      help="(optional) output plot (pdf) file name." )
+    parser.add_option("-l", dest="plot_title", default="",
+                      help="(optional) output title of the plot." )
+    parser.add_option("--ylim", dest="ylim", default="min,max",
+                      help="(optional) ylim of the plot" )
+    parser.add_option("--summary-only", action="store_true", dest="summary_only",default=False,
+                        help="save profile summary only (no data for individual features)")
+    parser.add_option("--compute-se", action="store_true", dest="compute_se",default=False,
+                        help="compute and plot standard deviation for each bin. used when --summary-only is on")
+    parser.add_option("--profile-only", action="store_true", dest="profile_only",default=False,
+                        help="save profile only (no plot)")
+    parser.add_option("--span", type="float", dest="span",default=0.1,
+                        help="loess span smooth parameter, 0.1 ~ 1")                    
+    
+    (options, args) = parser.parse_args()
+
+    if options.inputA == None or options.inputB == None:
+        parser.error("Please specify two input files!!")
+
+    if not options.quiet:
+        print "checking input file format..."
+        
+    ncol,ncol2 = checkFormat(options.inputA ,options.inputB,options.aformat)
+
+    if ncol2 < 6:
+        options.inputB = makeBed(options.inputB,ncol2)        
+        if not options.quiet:
+            print "fill up 6 columns"
+
+    if options.window > 0:
+        if not options.quiet:
+            print "making windows from "+options.inputB+"..." 
+        options.inputB = makeWindow(options.inputB,options.window)
+    
+    output = combineFilename(str(options.inputA),str(options.inputB))
+    
+    if not options.plot:
+        if options.aformat == "BAM":
+            cmd = "intersectBed -abam "+str(options.inputA)+" -b "+str(options.inputB) + ' -bed -split '
+        else:
+            cmd = "intersectBed -a "+str(options.inputA)+" -b "+str(options.inputB)
+        if options.strandness:
+            cmd = cmd + ' -s'
+        cmd = cmd +" -wo > "+ output+'-intersect.tmp.bed'
+        if not options.quiet:
+            print "search for overlappings: "+cmd
+        status = os.system(cmd)
+        if status != 0:
+            sys.exit(1)
+
+    
+    if not options.quiet:
+        print 'group reads mapped to the same region...'
+    
+    allReadsStart,allReadsEnd,regionStrand,regionStart,regionEnd = groupReadsMapped2aRegion(output+'-intersect.tmp.bed',ncol)
+
+    if len(allReadsStart) == 0:
+        if not options.quiet:
+            print 'no overlap found!!'
+        os.system('rm *tmp.*')
+        sys.exit(1)
+    
+    if not options.quiet:
+        print 'count number of reads mapped to each bin...'
+    
+    RegionProfile,nRead = createRegionProfile(allReadsStart,allReadsEnd,regionStrand,regionStart,regionEnd,options.nbins) 
+   
+    if options.output_data == None:
+        options.output_data = output+'.txt'
+
+    if options.summary_only:  
+        saveSummary(options.output_data,RegionProfile,options.nbins) 
+    
+    else:                 
+        saveProfile(options.output_data,RegionProfile,nRead)
+    
+    if not options.quiet:
+        print 'results saved to: '+ options.output_data 
+        
+    if not (options.summary_only or options.profile_only ):          
+        # visualize 
+
+        if options.window < 1:
+            xlab = 'relative position (bins)'
+        else:
+            xlab = 'relative position (bp)'
+	            
+        if options.output_plot == None:
+            options.output_plot = output+'.pdf'
+
+        title = options.plot_title+'\n n = '+str(len(RegionProfile))
+
+        rscript = open("tmp.r","w")
+        rscript.write("x <- read.table('"+options.output_data+"')\n")
+        rscript.write("pdf('"+options.output_plot+"')\n")
+        rscript.write("avg <- colSums(x[,3:ncol(x)])/nrow(x)\n")
+        rscript.write("err <- sd(x[,3:ncol(x)])/sqrt(nrow(x))\n")
+        
+        if options.window == 0:
+            rscript.write("xticks <- seq("+str(options.nbins)+")\n")
+        else:
+            rscript.write("xticks <- seq("+str(-options.window)+","+str(options.window)+",length.out="+str(options.nbins)+")\n")
+
+        if options.ylim != 'min,max':
+            rscript.write("ylim=c("+options.ylim+")\n")
+        else:
+            rscript.write("ylim=c(min(avg-err),max(avg+err))\n")
+        rscript.write("par(cex=1.5)\n")
+        #smooth
+        if options.span >= 0.1:
+            rscript.write("avg = loess(avg~xticks,span="+str(options.span)+")$fitted\n")
+            rscript.write("err = loess(err~xticks,span="+str(options.span)+")$fitted\n")
+        rscript.write("plot(xticks,avg,ylab='average coverage',main='"+title+"',xlab='"+xlab+"',type='l',lwd=0,ylim=ylim)\n")   
+        rscript.write("polygon(c(xticks,rev(xticks)),c(avg+err,rev(avg-err)),col='slateblue1',border=NA)\n")
+        rscript.write("lines(xticks,avg,type='l',lwd=1)\n")   
+        #rscript.write("xticks <- barplot(avg,names.arg=seq("+str(options.nbins)+"),ylab='average coverage',main='"+title+"',xlab='"+xlab+"',,ylim=c(min(avg-err),max(avg+err)))\n")
+        #rscript.write("arrows(xticks,avg+err, xticks, avg-err, angle=90, code=3, length=0.0,col='green')\n")
+        #rscript.write("lines(xticks,avg,lwd=2)\n")
+        #rscript.write("lines(xticks,avg-err,col='green')\n")
+        #rscript.write("lines(xticks,avg+err,col='green')\n")
+        rscript.write("dev.off()\n")
+        rscript.close()
+
+        os.system("R --vanilla < tmp.r")    
+    
+    # remove intermediate output
+    os.system('rm *tmp.*')
+
+    
+if __name__ == "__main__":
+    main()