python - What is the best way to calculate percentage of an iterating operation? -

i've written function saves numbers between 2 digit groups text file, step option save space , time, , couldn't figure out how show percentage value, tried this.

for length in range(int(limit_min), int(limit_max) + 1):      percent_quotient = 0     j=0     while j <= (int(length * "9")):         while len(str(j)) < length:             j = "0" + str(j)            percent_quotient+=1         j = int(j) + int(step)  # increasing dummy variable  length in range(int(limit_min), int(limit_max) + 1):     counter=1     = 0     while <= (int(length * "9")):         while len(str(i)) < length:             = "0" + str(i)  #          print "writing %s file. progress: %.2f percent." % (str(i),(float(counter)/percent_quotient)*100)         a.write(str(i) + "\n")  # gets written         = int(i) + int(step)  # increasing         counter+=1     if length != int(limit_max):         print "length %i done. moving on length of %i." % (length, length + 1)     else:         print "length %i done." % (length) a.close()  # closing file stream print "all done. closed file stream. new file size: %.2f megabytes." % (os.path.getsize(path) / float((1024 ** 2))) print "returning main..." 

what tried here make program iteration many times it, instead of writing file, made percent_quotient variable count how many times iteration going repeated. (i called j dummy variable since it's there break loop; i'm sorry if there expression this.) second part actual work , put counter variable, , divide percent_quotient , multiply 100 percentage.

the problem is, when tried make dictionary length of 1 length of 8, took minute count everything. imagine take longer if wanted make bigger dictionary.

my question is, there better/faster way of doing this?

i can't work out doing. looks it's doing this:

a = file('d:/whatever.txt', 'wb') limit_min = 1 limit_max = 5 step = 2  percent_quotient = (10 ** (limit_max - limit_min)) / step  in range(limit_min, 10**limit_max, step):     output = str(i).zfill(limit_max) + '\r\n'     a.write(output)      if % 100 < 2:         print "writing %s file. progress: %.2f percent." % (str(i),(float(i)/percent_quotient)*100)  a.close() 

if that's right, suggest:

• do less code looping , more math
• use string.zfill() instead of while len(str(num)) < length: "0" + str(num)
• don't overwhelm console output every single number, print status update every hundred numbers, or every thousand numbers, or so.
• do less str(int(str(int(str(int(str(int(...
• avoid "" + blah inside tight loops, if possible, causes strings rebuilt every time , it's particularly slow.