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0.1 float is greater than 0.1 double. I expected it to be false [duplicate]
...loat. float has 24 binary bits of precision, and double has 53. In binary, 0.1 is:
0.1₁₀ = 0.0001100110011001100110011001100110011001100110011…₂
^ ^ ^ ^
1 10 20 24
So if we round up at the 24th digit, we'll get
0.1₁₀ ~ 0.00011...
How to check if all elements of a list matches a condition?
I have a list consisting of like 20000 lists. I use each list's 3rd element as a flag. I want to do some operations on this list as long as at least one element's flag is 0, it's like:
...
What's the simplest way to test whether a number is a power of 2 in C++?
...
190
(n & (n - 1)) == 0 is best. However, note that it will incorrectly return true for n=0, so i...
Current time formatting with Javascript
...ar() - Returns the 4-digit year
getMonth() - Returns a zero-based integer (0-11) representing the month of the year.
getDate() - Returns the day of the month (1-31).
getDay() - Returns the day of the week (0-6). 0 is Sunday, 6 is Saturday.
getHours() - Returns the hour of the day (0-23).
getMinutes...
Check substring exists in a string in C
...
280
if(strstr(sent, word) != NULL) {
/* ... */
}
Note that strstr returns a pointer to the sta...
Specifying rails version to use when creating a new application
I have two versions of rails (2.1.0 and 2.2.2) installed in my computer.
7 Answers
7
...
Memoization in Haskell?
...efficiently the following function in Haskell, for large numbers (n > 108)
8 Answers
...
Android Left to Right slide animation
...ndroid:shareInterpolator="false">
<translate android:fromXDelta="-100%" android:toXDelta="0%"
android:fromYDelta="0%" android:toYDelta="0%"
android:duration="700"/>
</set>
This is for right to left animation:
<set xmlns:android="http://schemas.android...
Gray out image with CSS?
...age" src="something.jpg" />
</div>
css:
#myImage {
opacity: 0.4;
filter: alpha(opacity=40); /* msie */
}
/* or */
#wrapper {
opacity: 0.4;
filter: alpha(opacity=40); /* msie */
background-color: #000;
}
...
Compare double to zero using epsilon
...there is a 52-bit mantissa and 11-bit exponent. Let's break it to bits:
1.0000 00000000 00000000 00000000 00000000 00000000 00000000 × 2^0 = 1
The smallest representable number greater than 1:
1.0000 00000000 00000000 00000000 00000000 00000000 00000001 × 2^0 = 1 + 2^-52
Therefore:
epsilon ...