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Checking if a string can be converted to float in Python
I've got some Python code that runs through a list of strings and converts them to integers or floating point numbers if possible. Doing this for integers is pretty easy
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Computational complexity of Fibonacci Sequence
I understand Big-O notation, but I don't know how to calculate it for many functions. In particular, I've been trying to figure out the computational complexity of the naive version of the Fibonacci sequence:
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Memoization in Haskell?
...f :: Int -> Int
faster_f n = f_list !! n
That performs passably well, and replaces what was going to take O(n^3) time with something that memoizes the intermediate results.
But it still takes linear time just to index to find the memoized answer for mf. This means that results like:
*Main Dat...
What do hjust and vjust do when making a plot using ggplot?
...lot using ggplot, I spend a little while trying different values for hjust and vjust in a line like
2 Answers
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How to add an extra column to a NumPy array
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I think a more straightforward solution and faster to boot is to do the following:
import numpy as np
N = 10
a = np.random.rand(N,N)
b = np.zeros((N,N+1))
b[:,:-1] = a
And timings:
In [23]: N = 10
In [24]: a = np.random.rand(N,N)
In [25]: %timeit b = np.hstac...
Google Maps API 3 - Custom marker color for default (dot) marker
I've seen lots of other questions similar to this ( here , here and here ), but they all have accepted answers that don't solve my problem. The best solution I have found to the problem is the StyledMarker library, which does let you define custom colours for markers, but I can't get it to use ...
What causes imported Maven project in Eclipse to use Java 1.5 instead of Java 1.6 by default and how
I imported a Maven project and it used Java 1.5 even though I have 1.6 configured as my Eclipse default Preferences->Java->Installed JREs .
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Programmer Puzzle: Encoding a chess board state throughout a game
...e: I liked this topic so much I wrote Programming Puzzles, Chess Positions and Huffman Coding. If you read through this I've determined that the only way to store a complete game state is by storing a complete list of moves. Read on for why. So I use a slightly simplified version of the problem for ...
How does the static modifier affect this code?
...n, 2. Execution
In identification phase all static variables are detected and initialized with default values.
So now the values are:
A obj=null
num1=0
num2=0
The second phase, execution, starts from top to bottom. In Java, the execution starts from the first static members.
Here your first static...
How do I echo and send console output to a file in a bat script?
I have a batch script that executes a task and sends the output to a text file. Is there a way to have the output show on the console window as well?
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