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Check if UIColor is dark or bright?
...o use is ((Red value * 299) + (Green value * 587) + (Blue value * 114)) / 1000.
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Creating a comma separated list from IList or IEnumerable
...ng"};
string joined = string.Join(",", strings);
Detail & Pre .Net 4.0 Solutions
IEnumerable<string> can be converted into a string array very easily with LINQ (.NET 3.5):
IEnumerable<string> strings = ...;
string[] array = strings.ToArray();
It's easy enough to write the equiv...
Validate decimal numbers in JavaScript - IsNumeric()
...
2908
@Joel's answer is pretty close, but it will fail in the following cases:
// Whitespace strings...
Format number to 2 decimal places
...
You want to use the TRUNCATE command.
https://dev.mysql.com/doc/refman/8.0/en/mathematical-functions.html#function_truncate
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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
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Since dplyr 0.8 group_by gained the .drop argument that does just what you asked for:
df = data.frame(a=rep(1:3,4), b=rep(1:2,6))
df$b = factor(df$b, levels=1:3)
df %>%
group_by(b, .drop=FALSE) %>%
summarise(count_a=length(a)...
Imply bit with constant 1 or 0 in SQL Server
Is it possible to express 1 or 0 as a bit when used as a field value in a select statement?
8 Answers
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How to read the content of a file to a string in C?
...-codes for fseek, ftell and fread. (omitted for clarity).
char * buffer = 0;
long length;
FILE * f = fopen (filename, "rb");
if (f)
{
fseek (f, 0, SEEK_END);
length = ftell (f);
fseek (f, 0, SEEK_SET);
buffer = malloc (length);
if (buffer)
{
fread (buffer, 1, length, f);
}
fclo...
Generate a Hash from string in Javascript
...perty(String.prototype, 'hashCode', {
value: function() {
var hash = 0, i, chr;
for (i = 0; i < this.length; i++) {
chr = this.charCodeAt(i);
hash = ((hash << 5) - hash) + chr;
hash |= 0; // Convert to 32bit integer
}
return hash;
}
});
Source:
htt...
Sass - Converting Hex to RGBa for background opacity
...e, this would work just fine:
@mixin background-opacity($color, $opacity: 0.3) {
background: $color; /* The Fallback */
background: rgba($color, $opacity);
}
element {
@include background-opacity(#333, 0.5);
}
If you ever need to break the hex color into RGB components, though, you ...
How to initialize array to 0 in C?
...are automatically initialized to zero. If you have simply
char ZEROARRAY[1024];
at global scope it will be all zeros at runtime. But actually there is a shorthand syntax if you had a local array. If an array is partially initialized, elements that are not initialized receive the value 0 of the ap...