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How to find a deleted file in the project commit history?
...mit message
ba8d20e Another prior commit message affecting that file
cfea812 The first message for a commit in which that file appeared.
Checkout the file
If you choose the first-listed commit (the last chronologically, here bd8374c), the file will not be found, since it was deleted in that comm...
How do I replace NA values with zeros in an R dataframe?
...01.772 1106.315 1363.044 600
DT.for.set.sqln 787.3535 918.8733 1017.812 1002.042 1122.474 1321.860 600
Boxplot of Results
ggplot(perf_results, aes(x=expr, y=time/10^9)) +
geom_boxplot() +
xlab('Expression') +
ylab('Elapsed Time (Seconds)') +
scale_y_continuous(breaks = s...
Assign output of a program to a variable using a MS batch file
...
One way is:
application arg0 arg1 > temp.txt
set /p VAR=<temp.txt
Another is:
for /f %%i in ('application arg0 arg1') do set VAR=%%i
Note that the first % in %%i is used to escape the % after it and is needed when using the above code in a batch file rather than...
What exactly does big Ө notation represent?
...rst let's understand what big O, big Theta and big Omega are. They are all sets of functions.
Big O is giving upper asymptotic bound, while big Omega is giving a lower bound. Big Theta gives both.
Everything that is Ө(f(n)) is also O(f(n)), but not the other way around.
T(n) is said to be in Ө(f(n...
Difference between Big-O and Little-O Notation
...0 <= f(x) <= k g(x) holds for all x > a.
Note that O(g) is the set of all functions for which this condition holds.
f ∈ o(g) says, essentially
For every choice of a constant k > 0, you can find a constant a such that the inequality 0 <= f(x) < k g(x) holds for all x > ...
Designing function f(f(n)) == -n
...(y) = -x, and f(-y) = x.
So, we need to divide all integers except 0 into sets of 4, but we have an odd number of such integers; not only that, if we remove the integer that doesn't have a positive counterpart, we still have 2(mod4) numbers.
If we remove the 2 maximal numbers left (by abs value), ...
What are the differences between a multidimensional array and an array of arrays in C#?
... 4.776 4.635 5.864
7.414 13.196 11.940 11.832 11.675 11.811 11.812 12.964 11.885 11.751
11.355 10.788 10.527 10.541 10.745 10.723 10.651 10.930 10.639 10.595
Source code:
using System;
using System.Diagnostics;
static class ArrayPref
{
const string Format = "{0,7:0.000}...
Test for non-zero length string in Bash: [ -n “$var” ] or [ “$var” ]
...-----------------------------------+------------------------------------
unset| false false true false true true | false false false false true true
null | false false true false true true | false false false false true true
space| false true true true true false| true true true true f...
Algorithm to return all combinations of k elements from n
...rse memory and pretty quickly, you'll have problems by 20 elements in your set -- 20C3 = 1140. And if you want to iterate over the set it's best to use a modified gray code algorithm so you aren't holding all of them in memory. These generate the next combination from the previous and avoid repetiti...
Memoization in Haskell?
...d that f !! 143 exists, but its exact value is not calculated. It's still set as some unknown result of a calculation. The only exact values calculated are the ones needed.
So initially, as far as how much has been calculated, the program knows nothing.
f = ....
When we make the request f !! ...