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Difference between two dates in Python
... d2 = d2.strftime("%Y-%m-%d")
return abs((d2 - d1).days)
This will convert your datetime objects to strings but, two things
1) Trying to do d2 - d1 will fail as you cannot use the minus operator on strings and
2) If you read the first line of the above answer it stated, you want to use the ...
Is it possible to specify condition in Count()?
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When working with boolean fields you can use this : SUM(CONVERT(int, IsManager))
– Simon_Weaver
Apr 4 '17 at 23:09
2
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How to format numbers by prepending 0 to single-digit numbers?
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If the number is higher than 9, convert the number to a string (consistency). Otherwise, add a zero.
function n(n){
return n > 9 ? "" + n: "0" + n;
}
n( 9); //Returns "09"
n(10); //Returns "10"
n(999);//Returns "999"
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Hidden features of WPF and XAML?
...into words just how much I love that feature. I hated having tons of value converters laying around.
– Rob
Jul 14 '09 at 13:53
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Format bytes to kilobytes, megabytes, gigabytes
...] Number of digits after the decimal point (eg. 1)
* @return string Value converted with unit (eg. 25.3KB)
*/
function formatBytes($bytes, $precision = 2) {
$unit = ["B", "KB", "MB", "GB"];
$exp = floor(log($bytes, 1024)) | 0;
return round($bytes / (pow(1024, $exp)), $precision).$unit[...
How to subtract X days from a date using Java calendar?
... @ShahzadImam, check out DateTimeFormat. It will allow you to convert DateTime instances to strings using arbitrary formats. It's very similar to the java.text.DateFormat class.
– Mike Deck
Feb 28 '12 at 15:40
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LINGO使用指南 - 更多技术 - 清泛网 - 专注C/C++及内核技术
LINGO使用指南LINGO使用指南LINGO是用来求解线性和非线性优化问题的简易工具。LINGO内置了一种建立最优化模型的语言，可以简便地表达大规模问题，利用LIN...
LINGO是用来求解线性和非线性优化问题的简易工具。LINGO内置了一种建...
Getting a File's MD5 Checksum in Java
... return complete.digest();
}
// see this How-to for a faster way to convert
// a byte array to a HEX string
public static String getMD5Checksum(String filename) throws Exception {
byte[] b = createChecksum(filename);
String result = "";
for (int i=0; i < b.lengt...
Repeat each row of data.frame the number of times specified in a column
...q(nrow(df)), df$freq), 1:2]
The code for data.table is a tad cleaner:
# convert to data.table by reference
setDT(df)
df.expanded <- df[rep(seq(.N), freq), !"freq"]
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When to use DataContract and DataMember attributes?
...the Data Contract Serializer by default to serialize and deserialize data (convert it to and from XML). All .NET Framework primitive types, such as integers and strings, as well as certain types treated as primitives, such as DateTime and XmlElement, can be serialized with no other preparation and a...