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Why does the default parameterless constructor go away when you create one with parameters
In C#, C++ and Java, when you create a constructor taking parameters, the default parameterless one goes away. I have always just accepted this fact, but now I've started wondering why.
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How to generate the “create table” sql statement for an existing table in postgreSQL
I have created a table in postgreSQL. I want to look at the SQL statement used to create the table but cannot figure it out.
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How to convert a Map to List in Java?
What is the best way to convert a Map<key,value> to a List<value> ? Just iterate over all values and insert them in a list or am I overlooking something?
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What's the difference between an inverted index and a plain old index?
In software engineering we create indexes all the time (e.g., in databases) but I also hear a lot of people talk about inverted indices. Is there something fundamentally different between the two? They sound like the same thing.
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What is the difference between integration and unit tests?
I know the so-called textbook definition of unit tests and integration tests. What I am curious about is when it is time to write unit tests... I will write them to cover as many sets of classes as possible.
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Is there a foreach in MATLAB? If so, how does it behave if the underlying data changes?
Is there a foreach structure in MATLAB? If so, what happens if the underlying data changes (i.e. if objects are added to the set)?
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When should I use a composite index?
For example, I have a homes table:
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Is nested function a good approach when required by only one function? [closed]
Let's say that a function A is required only by function B , should A be defined inside B?
12 Answers
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pandas dataframe columns scaling with sklearn
I have a pandas dataframe with mixed type columns, and I'd like to apply sklearn's min_max_scaler to some of the columns. Ideally, I'd like to do these transformations in place, but haven't figured out a way to do that yet. I've written the following code that works:
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Return array in a function
I have an array int arr[5] that is passed to a function fillarr(int arr[]) :
19 Answers
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