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What is the difference between NaN and None?

...dcsv() and then assigning the values to a dictionary. The columns contain strings of numbers and letters. Occasionally there are cases where a cell is empty. In my opinion, the value read to that dictionary entry should be None but instead nan is assigned. Surely None is more descriptive of a...
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Python pandas Filtering out nan from a data selection of a column of strings

...403%2fpython-pandas-filtering-out-nan-from-a-data-selection-of-a-column-of-strings%23new-answer', 'question_page'); } ); Post as a guest Name ...
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Should you declare methods using overloads or optional parameters in C# 4.0?

...meters feature of 4.0. It gets rid of the ridiculous ... public void M1( string foo, string bar ) { // do that thang } public void M1( string foo ) { M1( foo, "bar default" ); // I have always hated this line of code specifically } ... and puts the values right where the caller can see the...
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Ruby: Merging variables in to a string

I'm looking for a better way to merge variables into a string, in Ruby. 7 Answers 7 ...
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Converting string into datetime

I've got a huge list of date-times like this as strings: 20 Answers 20 ...
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how to get the cookies from a php curl into a variable

...each response header line. The function will receive the curl object and a string with the header line. You can use a code like this (adapted from TML response): $cookies = Array(); $ch = curl_init('http://www.google.com/'); // Ask for the callback. curl_setopt($ch, CURLOPT_HEADERFUNCTION, "curlRe...
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JSP tricks to make templating easier?

...y '.', and /WEB-INF/templates/ prefix if it does not start with a '/') String template = (String)jspContext.getAttribute("template"); if (template != null) { if (!template.contains(".")) template += ".jsp"; if (!template.startsWith("/")) template = "/W...
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How and where are Annotations used in Java?

...notations such as NotNull, like in: public void processSomething(@NotNull String text) { ... } which allows the compiler to warn you about improper/unchecked uses of variables and null values. Another more advanced application for annotations involves reflection and annotation processing at ...
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Deep cloning objects

... Your example illustrates the problem. Suppose you have a Dictionary<string, Customer>. Should the cloned Dictionary have the same Customer objects as the original, or copies of those Customer objects? There are reasonable use cases for either one. But ICloneable doesn't make clear which...
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regex.test V.S. string.match to know if a string matches a regular expression

Many times I'm using the string match function to know if a string matches a regular expression. 3 Answers ...