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Count number of occurrences of a given substring in a string
How can I count the number of times a given substring is present within a string in Python?
35 Answers
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Which MySQL datatype to use for an IP address? [duplicate]
...r conversion:
'INSERT INTO `table` (`ipv6`) VALUES ("'.mysqli_real_escape_string(inet_pton('2001:4860:a005::68')).'")'
'SELECT `ipv6` FROM `table`'
$ipv6 = inet_pton($row['ipv6']);
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Pass a data.frame column name to a function
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Is there any way to pass the column name not as a string?
– kmm
Apr 14 '10 at 23:13
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Why is the default value of the string type null instead of an empty string?
It's quite annoying to test all my strings for null before I can safely apply methods like ToUpper() , StartWith() etc...
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Program only crashes as release build — how to debug?
... was indeed caused by a buffer overflow, caused a single byte difference:
char *end = static_cast<char*>(attr->data) + attr->dataSize;
This is a fencepost error (off-by-one error) and was fixed by:
char *end = static_cast<char*>(attr->data) + attr->dataSize - 1;
The wei...
Start thread with member function
...t;< "i am member1" << std::endl;
}
void member2(const char *arg1, unsigned arg2) {
std::cout << "i am member2 and my first arg is (" << arg1 << ") and second arg is (" << arg2 << ")" << std::endl;
}
std::thread member1Thr...
Java 8 List into Map
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Based on Collectors documentation it's as simple as:
Map<String, Choice> result =
choices.stream().collect(Collectors.toMap(Choice::getName,
Function.identity()));
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How do you query for “is not null” in Mongo?
...roposition:
db.collection_name.find({"field_name":{$type:2}}) //type:2 == String
You can check on the required attribute's type, it will return all the documents that its field_name queried contains a value because you are checking on the filed's type else if it is null the type condition doesn't...
Can overridden methods differ in return type?
...erriding method should be the same.
e.g. if the return type is int, float, string then it should be same
Case 2: If the return type is derived data type:
Output: If the return type of the parent class method is derived type then the return type of the overriding method is the same derived data typ...
Recommended method for escaping HTML in Java
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StringEscapeUtils from Apache Commons Lang:
import static org.apache.commons.lang.StringEscapeUtils.escapeHtml;
// ...
String source = "The less than sign (<) and ampersand (&) must be escaped before using them in HTM...