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How to find where a method is defined at runtime?
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How to print binary tree diagram?
...ublic class BTreePrinterTest {
private static Node<Integer> test1() {
Node<Integer> root = new Node<Integer>(2);
Node<Integer> n11 = new Node<Integer>(7);
Node<Integer> n12 = new Node<Integer>(5);
Node<Integer> n21 ...
What does the “map” method do in Ruby?
...e from the block (the original object is unchanged unless you use map!):
[1, 2, 3].map { |n| n * n } #=> [1, 4, 9]
Array and Range are enumerable types. map with a block returns an Array. map! mutates the original array.
Where is this helpful, and what is the difference between map! and each...
Elegant Python function to convert CamelCase to snake_case?
...anymore):
def camel_to_snake(name):
name = re.sub('(.)([A-Z][a-z]+)', r'\1_\2', name)
return re.sub('([a-z0-9])([A-Z])', r'\1_\2', name).lower()
print(camel_to_snake('camel2_camel2_case')) # camel2_camel2_case
print(camel_to_snake('getHTTPResponseCode')) # get_http_response_code
print(camel_t...
When is “i += x” different from “i = i + x” in Python?
...ts than the standard notation of i = i + . Is there a case in which i += 1 would be different from i = i + 1 ?
3 Answer...
What's the difference between echo, print, and print_r in PHP?
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How to drop a list of rows from Pandas dataframe?
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How to pass a single object[] to a params object[]
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100
A simple typecast will ensure the compiler knows what you mean in this case.
Foo((object)new ...
Replacing Pandas or Numpy Nan with a None to use with MysqlDB
...n use where, it's worth noting that you can do this natively in pandas:
df1 = df.where(pd.notnull(df), None)
Note: this changes the dtype of all columns to object.
Example:
In [1]: df = pd.DataFrame([1, np.nan])
In [2]: df
Out[2]:
0
0 1
1 NaN
In [3]: df1 = df.where(pd.notnull(df), None...