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Safest way to convert float to integer in python?
...s small enough, but different representations are possible where int(floor(2.3)) might be 1.
To quote from Wikipedia,
Any integer with absolute value less than or equal to 224 can be exactly represented in the single precision format, and any integer with absolute value less than or equal to 25...
Removing duplicates from a list of lists
...
>>> k = [[1, 2], [4], [5, 6, 2], [1, 2], [3], [4]]
>>> import itertools
>>> k.sort()
>>> list(k for k,_ in itertools.groupby(k))
[[1, 2], [3], [4], [5, 6, 2]]
itertools often offers the fastest and most powerf...
Does the ternary operator exist in R?
... if-else is equivalent to ?:.
> a <- 1
> x <- if(a==1) 1 else 2
> x
[1] 1
> x <- if(a==2) 1 else 2
> x
[1] 2
The power of R is vectorization. The vectorization of the ternary operator is ifelse:
> a <- c(1, 2, 1)
> x <- ifelse(a==1, 1, 2)
> x
[1] 1 2 1
>...
Why do enum permissions often have 0, 1, 2, 4 values?
Why are people always using enum values like 0, 1, 2, 4, 8 and not 0, 1, 2, 3, 4 ?
7 Answers
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Limiting floats to two decimal points
...
26 Answers
26
Active
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How to get all possible combinations of a list’s elements?
... list with 15 numbers in, and I need to write some code that produces all 32,768 combinations of those numbers.
27 Answers...
Filter rows which contain a certain string
...
263
The answer to the question was already posted by the @latemail in the comments above. You can ...
Get distance between two points in canvas
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211
You can do it with pythagoras theorem
If you have two points (x1, y1) and (x2, y2)
then you c...
Numpy - add row to array
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122
What is X? If it is a 2D-array, how can you then compare its row to a number: i < 3?
EDIT a...
App Inventor 2 手机蓝牙及语音控制 - App Inventor 2 中文网 - 清泛IT论坛，有思想、有深度
...标】
1.掌握蓝牙客户端或服务端组件的使用；
2.学会编写手机蓝牙APP，并向Arduino发送控制指令；
3.学会编写手机语音控制程序，并能通过语音控制Arduino等设备。 【项目范例】
1. 情境
通过对APPInvent...