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Convert Pandas column containing NaNs to dtype `int`
I read data from a .csv file to a Pandas dataframe as below. For one of the columns, namely id , I want to specify the column type as int . The problem is the id series has missing/empty values.
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What's wrong with nullable columns in composite primary keys?
...keys is not clean relational database design.
If there are two entities A and B where A can optionally be related to B, the clean solution is to create a resolution table (let's say AB). That table would link A with B: If there is a relationship then it would contain a record, if there isn't then i...
Is it possible to read from a InputStream with a timeout?
...tream always returns 0.
This method should be overridden by subclasses.
And indeed, the concrete input stream classes do override available(), providing meaningful values, not constant 0s.
Second Caveat: Ensure you use carriage-return when typing input in Windows.
If using System.in, your progr...
Can I simultaneously declare and assign a variable in VBA?
I'm new to VBA and want to know if I can convert the following declaration and assignment into one line:
5 Answers
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What is self-documenting code and can it replace well documented code? [closed]
...mments (Doxygen, JavaDoc, XML comments etc.) for every class, member, type and method AND
clearly comments any parts of the code that are not self-documenting AND
writes a comment for each block of code that explains the intent, or what the code does on a higher abstraction level (i.e. find all file...
Is it possible to declare two variables of different types in a for loop?
...se a structured binding declaration. The syntax has been supported in gcc and clang for years (since gcc-7 and clang-4.0) (clang live example). This allows us to unpack a tuple like so:
for (auto [i, f, s] = std::tuple{1, 1.0, std::string{"ab"}}; i < N; ++i, f += 1.5) {
// ...
}
The above...
href=“tel:” and mobile numbers
...ant to dial via the international trunk, you need to drop the trunk prefix and replace it with the international dialing prefix
+ - Short hand for the country trunk number
61 - Country code for Australia
4 - Area code for a mobile telephone
1234 5678 - Mobile telephone number...
JMS and AMQP - RabbitMQ
I am trying to understand what JMS and how it is connected to AMQP terminology.
I know JMS is an API and AMQP is a protocol.
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Difference between size_t and unsigned int?
I am so confused about size_t . I have searched on the internet and everywhere mentioned that size_t is an unsigned type so, it can represent only non-negative values.
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how do I make a single legend for many subplots with matplotlib?
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There is also a nice function get_legend_handles_labels() you can call on the last axis (if you iterate over them) that would collect everything you need from label= arguments:
handles, labels = ax.get_legend_handles_labels()
fig.legend(handles, labels, loc='upper c...