my python code is getting a (list index out of range error) ...can anyone get me a reason why -


given below python code supposed read values list , gets sum of values after squaring each of them.

def squareeach(nums):     in nums[:-1]:         s=nums[i]*nums[i]         nums[i]=s   def sums(num):     sum1=1     in num[:-1]:         sum1=sum1+num[i]     return sum1   def tonumbers(strlist):     in range(len(strlist)):         strlist[i]=int(strlist[i])  file=raw_input("enter filename: ") openf=open(file,'w') openf.write("1 2 3 4 5 6 7 8 9 10") openf=open(file,'r')   s='' in openf:     s=i s=string.split(s)  in range(len(s)):     s[i]=int(i) squareeach(s) s=sums(s) print s

this program , getting error. why?

python loops iterate on elements (not indices) of list:

for in [1, 2, 4]:    print  # prints 1, 2 , 4

you'll have modify existing 1 working index of each element:

def squareeach(nums):     in range(len(nums)):         nums[i] = nums[i]*nums[i]

although make function creates new list instead:

def squareeach(nums):     return [n**2 n in nums]

Comments

Post a Comment

Popular posts from this blog

asp.net mvc 3 - Using mvc3, I need to add a username/password to the sql connection string at runtime -

i see how build string using stringbuilders (sql/entity framework); do cause connection string used in dbcontext? example context: public class pophistorydbcontext : dbcontext { public dbset<pophistory> histories {get;set} } public class pophistoryrepository: ihistoryrepository { private pophistorydbcontext context = new pophistorydbcontext(); public iqueryable<pophistory> histories{ {return context.histories;} } } example usage in controller: public class historycontroller : controller { private ihistoryrepository repository = new pophistoryrepository(); var histories = h in repository.histories (h.modifytimestamp > today) select h; if (!string.isnullorempty(searchstring)) { histories = histories.where(h => h.dn.toupper().contains(searchstring.toupper())); } thank you
Read more

kineticjs - draw multiple lines and delete individual line -

i can draw multiple lines on canvas; added layer using drawscene dlayera1.add(line); line.getpoints()[0].x = mousepos.x; line.getpoints()[0].y = mousepos.y; line.getpoints()[1].x = mousepos.x; line.getpoints()[1].y = mousepos.y; moving = true; dlayera1.drawscene(); http://jsfiddle.net/user373721/xzead/1/ . is there way delete individual line? currently, you'll have modify points array this: line.getpoints()[0].splice(index, 1); since arrays modified reference, modifying returned array modifies "source of truth" points array attr
Read more

thumbnails - jQuery image rotate on hover -

any chance change image src on hover , count 10 , again first? this need, default thumb, flv-3.jpg ! <img src="/thumbs/e/b/d/6/d/ebd6d2d6d99e/ebd6d2d6d99e.flv-3.jpg" /> on mouse hover need change number flv-1.jpg flv-2.jpg flv-3.jpg flv-4.jpg etc.. up 10, , again , start number 1, when move mouse thumbs need default thumb flv-3.jpg this im use not solutions, var _thumbs = new array(); function changethumb(index, i, num_thumbs, path) { if (_thumbs[index]) { document.getelementbyid(index).src = path + + ".jpg"; preload = new image(); preload_image_id = (i + 1 > num_thumbs) ? 1 : + 1; preload.src = path + preload_image_id + ".jpg"; = % num_thumbs; i++; settimeout("changethumb('" + index + "'," + + ", " + num_thumbs + ", '" + path + "')", 800) } } function startthumbchange(index, nu
Read more