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How to select rows from a DataFrame based on column values?
...type, this is a very useful way to do it.
Given
np.random.seed([3,1415])
d1 = pd.DataFrame(np.random.randint(10, size=(10, 5)), columns=list('ABCDE'))
d1
A B C D E
0 0 2 7 3 8
1 7 0 6 8 6
2 0 2 0 4 9
3 7 3 2 4 3
4 3 6 7 7 4
5 5 3 7 5 9
6 8 7 6 4 7
7 6 ...
C# Double - ToString() formatting with two decimal places but no rounding
...String("0.##"); //24.1
d3.ToString("0.##"); //24
http://dobrzanski.net/2009/05/14/c-decimaltostring-and-how-to-get-rid-of-trailing-zeros/
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How can I determine whether a 2D Point is within a Polygon?
...oat v1y2,
float v2x1, float v2y1, float v2x2, float v2y2
) {
float d1, d2;
float a1, a2, b1, b2, c1, c2;
// Convert vector 1 to a line (line 1) of infinite length.
// We want the line in linear equation standard form: A*x + B*y + C = 0
// See: http://en.wikipedia.org/wiki/Li...
代码块超过1.2w编译apk报错问题 - App Inventor 2 中文网 - 清泛IT社区，为创新赋能！
...com.android.tools.r8.utils.R0.a(R8_8.2.2-dev_53a55043254cc5be8ef500331bba25d1b4ca4bc2cd66c555d4358bf672a1f10a:126)
[java] at com.android.tools.r8.D8.main(R8_8.2.2-dev_53a55043254cc5be8ef500331bba25d1b4ca4bc2cd66c555d4358bf672a1f10a:5)
&nb...
Reordering of commits
... -> master) Fourth commit
9a24b81 Third commit
7bdfb68 Second commit
186d1e0 First commit
I want to reorder commits 9a24b81 (Third commit) and 7bdfb68 (Second commit). To do this, I first find the commit before the first commit we want to change. This is commit 186d1e0 (First commit).
The comm...
C# operator overload for `+=`?
...lib]System.Decimal)
IL_0016: stloc.0
Now lets see this code:
Decimal d1 = 10M;
d1 += 10M;
Console.WriteLine(d1);
And IL-code for this:
IL_0000: nop
IL_0001: ldc.i4.s 10
IL_0003: newobj instance void [mscorlib]System.Decimal::.ctor(int32)
IL_0008: stloc.0
IL_0009: ldloc....
Applying a function to every row of a table using dplyr?
...r_0.8.0.9000
library(purrr) # purrr_0.2.99.9000
library(microbenchmark)
d1_count <- 1000
d2_count <- 10
d1 <- data.frame(a=runif(d1_count))
do_fn <- function(row){data.frame(a=row$a, b=runif(d2_count))}
do_fn2 <- function(a){data.frame(a=a, b=runif(d2_count))}
op <- microbenc...
Why is my git repository so big?
...Edit: Here's Ian's one liner for recreating all branches in the new repo:
d1=#original repo
d2=#new repo (must already exist)
cd $d1
for b in $(git branch | cut -c 3-)
do
git checkout $b
x=$(git rev-parse HEAD)
cd $d2
git checkout -b $b $x
cd $d1
done
...
Finding the number of days between two dates
...e() and strftime() syntax. The time interval syntax can be found here: php.net/manual/en/dateinterval.format.php
– Andrew
Jun 4 '13 at 7:56
1
...
What does “mro()” do?
...s(self):
print('I am from B3 class')
# Diamond inheritance
class D1(B1, B3):
pass
class D2(B1, B2):
pass
d1_instance = D1()
d1_instance.dothis()
# I am from B1 class
print(D1.__mro__)
# (<class '__main__.D1'>, <class '__main__.B1'>, <class '__main__.B3'>, <...