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Android emulator-5554 offline
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edited Aug 8 '19 at 9:50
louloulfx
4588 bronze badges
answered Jan 24 '14 at 10:27
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Why is isNaN(null) == false in JS?
...false.
So in the specific case x = null, null is converted to the number 0, (try evaluating Number(null) and see that it returns 0,) and isNaN(0) returns false. A string that is only digits can be converted to a number and isNaN also returns false. A string (e.g. 'abcd') that cannot be converted t...
How to format a Java string with leading zero?
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In case you have to do it without the help of a library:
("00000000" + "Apple").substring("Apple".length())
(Works, as long as your String isn't longer than 8 chars.)
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How is a CRC32 checksum calculated?
...e polynomial for CRC32 is:
x32 + x26 + x23 + x22 + x16 + x12 + x11 + x10 + x8 + x7 + x5 + x4 + x2 + x + 1
Wikipedia
CRC calculation
Or in hex and binary:
0x 01 04 C1 1D B7
1 0000 0100 1100 0001 0001 1101 1011 0111
The highest term (x32) is usually not explicitly written, so it can i...
Efficient way to determine number of digits in an integer
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107
Well, the most efficient way, presuming you know the size of the integer, would be a lookup. S...
adding noise to a signal in python
I want to add some random noise to some 100 bin signal that I am simulating in Python - to make it more realistic.
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How to get the type of a variable in MATLAB?
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answered Feb 23 '09 at 17:36
Daniel LeCheminantDaniel LeCheminant
47.3k1515 gold badges115115 silver badges113113 bronze badges
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Circle line-segment collision detection algorithm?
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206
Taking
E is the starting point of the ray,
L is the end point of the ray,
C is the cente...
Group by multiple columns in dplyr, using string vector input
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data = data.frame(
asihckhdoydkhxiydfgfTgdsx = sample(LETTERS[1:3], 100, replace=TRUE),
a30mvxigxkghc5cdsvxvyv0ja = sample(LETTERS[1:3], 100, replace=TRUE),
value = rnorm(100)
)
# get the columns we want to average within
columns = names(data)[-3]
library(dplyr)
df1 <- data %>%...
How do I output text without a newline in PowerShell?
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edited Oct 9 '10 at 18:56
Jay Bazuzi
39.9k1212 gold badges101101 silver badges158158 bronze badges
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