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get string value from HashMap depending on key name
...;>();
Using this will make your code cleaner and also you don't have to convert the result of hs.get("my_code") to string as by default it returns value of string if at entry time one has kept value as a string.
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How does the const constructor actually work?
...ecognize equivalence of these constants.
Canonicalization:
A process for converting data that has more than one possible representation into a "standard" canonical representation. This can be done to compare different representations for equivalence, to count the number of distinct data structures...
Why does the indexing start with zero in 'C'?
...pression (such as the name of an array object) is usually, but not always, converted to a pointer to the first element. Example: sizeof arr yields the size of the array object, not the size of a pointer.
– Keith Thompson
Sep 21 '11 at 7:44
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'and' (boolean) vs '&' (bitwise) - Why difference in behavior with lists vs numpy arrays?
...f the statement 'my car has wheels') => number
If python knows how to convert the statements to numeric values, then it will do so and compute the bitwise-and of the two values. This may lead you to believe that & is interchangeable with and, but as with the above example they are different...
How can I find the number of days between two Date objects in Ruby?
... will have a 1 concatenated to the end. yikes! you may want to use to_i to convert the result to an integer
– jwal
Jan 24 '12 at 18:07
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How do I profile memory usage in Python?
I've recently become interested in algorithms and have begun exploring them by writing a naive implementation and then optimizing it in various ways.
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Append a NumPy array to a NumPy array
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Actually one can always create an ordinary list of numpy arrays and convert it later.
In [1]: import numpy as np
In [2]: a = np.array([[1,2],[3,4]])
In [3]: b = np.array([[1,2],[3,4]])
In [4]: l = [a]
In [5]: l.append(b)
In [6]: l = np.array(l)
In [7]: l.shape
Out[7]: (2, 2, 2)
In [8]...
(![]+[])[+[]]… Explain why this works
...e second operand of the addition, an empty Array, [], this is made just to convert the false value to String, because the string representation of an empty array is just an empty string, is equivalent to:
false+[]; // "false"
false+''; // "false"
The last part, the pair of square brackets after t...
How do I parse JSON in Android? [duplicate]
...;
} catch (Exception e) {
Log.e("Buffer Error", "Error converting result " + e.toString());
}
// try parse the string to a JSON object
try {
jObj = new JSONObject(json);
} catch (JSONException e) {
Log.e("JSON Parser", "Err...
Combine two columns of text in pandas dataframe
...arter"]
If one (or both) of the columns are not string typed, you should convert it (them) first,
df["period"] = df["Year"].astype(str) + df["quarter"]
Beware of NaNs when doing this!
If you need to join multiple string columns, you can use agg:
df['period'] = df[['Year', 'quarter', ...]].a...