| | I have a list like:
list = [[1,2,3],[4,5,6],[7,8,9]]
I want to append a number at the start of every value in the list programmatically, say the number is 9. I want the new ... | l = range(100)
for i in ...
| The problem
My concern is the following: I am storing a relativity large dataset in a classical python list and in order to process the data I must iterate over the list ... | So I am relatively new to Python and I am having trouble working with 2D Lists.
Here's my code:
data = [[None]*5]*5
data[0][0] = 'Cell A1'
print data
and here is the output (formatted for readability):
[['Cell ...
| I'm doing some performance-critical Python work and want to create a function that removes a few elements from a list if they meet certain criteria. I'd rather not create any ... | I'm trying to modify items in a list using a for loop, but I get an error (see below). Sample code:
#!/usr/bin/env python
# *-* coding: utf8 *-*
data = []
data.append("some")
data.append("example")
data.append("data")
data.append("here")
for item in data:
...
| How can I modify the list below:
[('AAA', '1-1', 1, (1.11, (2.22, 3.33))), ('BBB', '2-2', 2, (4.44, (5.55, 6.66))), ('CCC', '3-3', 3, (7, (8, 9)))]
into something like this:
[('AAA', '1-1', 1, 1.11, 2.22, ...
| | Now I know that it is not safe to modify the list during an iterative looping. However, suppose I have a list of strings, and I want to strip the strings ... | I'm trying to generate a list of primes using the this method. I need to loop through every number 2...n and check it for multiples of 2...n. For some ... | How to handle nested lists in Python? I am having problem figuring out the syntax. Like example:
>>> l = [[1, 2, 3], [5, 6, 7]]
I want to square all the elements ... | I was thinking of writing a function to normalize some data. A simple approach is
def normalize(l, aggregate=sum, norm_by=operator.truediv):
aggregated=aggregate(l)
for i in range(len(l)):
...
| >>> list1 = []
>>> list2 = list1
>>> list2 += [1]
>>> print list1
[1]
Comparing this to
>>> list1 = []
>>> list2 = list1
>>> list2 = list2 + [1]
>>> print list1
[]
Is there a reason why ... | Initially, I wasn't sure whether this was the appropriate place for this question, but after reading through the FAQ I feel fairly confident the topic is acceptable.... Furthermore I wasn't sure ... | I have a hunch that I need to access an item in a list (of strings), modify that item (as a string), and put it back in the list in the ... | | i want to duplicate a list and modify the duplicate, but when i try this, i end up modifying the original as well.
a highly simplified version of my problem
list = [2,3,6,8,9,6,7,4,56,8,9,6,7,8]
new_list ...
| I've this list with tuples:
l = [('a','b'),('c','d'),('e','f')]
And two parameters: a key value, and a new value to modify. For example,
key = 'a'
new_value= 'B' # it means, modify with 'B' the value ...
| How to modify program of generation for saving words in list and choosing them with random.choice() previously do import random?
where is mistake? its not working correct
def generate_model(cfdist,word,num=15):
...
| Hi, I am writing a script wherein i am trying to modify the values in a list of lists. listmap = (("X",1), ("Y",2),("Z",3)) def updatevalue(listmap,key,value): for s in listmap: if s[0] == key: s[1] = value print listmap updatevalue(listmap,"X",5) print listmap Get the following error : (('X', 1), ('Y', 2), ('Z', 3)) Traceback (most recent call last): File "parsefile.py", line 50, ... | def add_column(matrix): newmat = matrix[:] for i, index in enumerate(newmat): print 'newmat[{pos}] id: {new}\nmatrix[{pos}] id: {mat}'.format( pos=i, new=id(newmat[i]), mat=id(matrix[i])) newmat += ... | I have a long list of dynamically created objects: Code: Select all class NewObject: def __init__(self, arg1, arg2, arg3): # misc code def lotsacode(self, input_data, num_objects): obj_list = [] # a bit of evaluation... for obj in ... | Hi all I am very new to python and lists in python are certainly confusing me :S I have a list (say A) that contains certain number of widths and heights this is a pseudo code for what i am trying to do for i going from 0 to 7 if i is 0 then copy list A into a list ... | Hi, I am a beginner. Please look at the following code: >>> a = ['spam', 'eggs', 100, 'spam', 'eggs', 100, 'spam', 'eggs', 100, 'Boo!'] >>> a[0]=a >>> print a [[...], 'eggs', 100, 'spam', 'eggs', 100, 'spam', 'eggs', 100, 'Boo!'] >>> print a[0][0][0] [[...], 'eggs', 100, 'spam', 'eggs', 100, 'spam', 'eggs', 100, 'Boo!'] I am not able to understand what exactly is ... | | Code: Select all >>> def CrearMatriz(m,numFilas,numColumnas): for i in range(numFilas): m.append([0]*numColumnas) >>> M = [] >>> CrearMatriz(M,4,3) >>> print M [[0, 0, 0], [0, 0, 0], [0, 0, 0], [0, 0, 0]] >>> M[1][0] = 35 >>> print M [[0, 0, 0], [35, 0, 0], [0, 0, 0], [0, ... |
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