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How to delete an element from an array in C#
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10 Answers
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Create Pandas DataFrame from a string
... from io import StringIO
import pandas as pd
TESTDATA = StringIO("""col1;col2;col3
1;4.4;99
2;4.5;200
3;4.7;65
4;3.2;140
""")
df = pd.read_csv(TESTDATA, sep=";")
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Take the content of a list and append it to another list
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You probably want
list2.extend(list1)
instead of
list2.append(list1)
Here's the difference:
>>> a = range(5)
>>> b = range(3)
>>> c = range(2)
>>> b.append(a)
>>> b
[0, 1, 2, [0, 1, 2, 3, 4]]
>>> c.ex...
How to append multiple values to a list in Python
...r any other thing that provides a sequence of values.
>>> lst = [1, 2]
>>> lst.append(3)
>>> lst.append(4)
>>> lst
[1, 2, 3, 4]
>>> lst.extend([5, 6, 7])
>>> lst.extend((8, 9, 10))
>>> lst
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
>>> ...
What does ** (double star/asterisk) and * (star/asterisk) do for parameters?
...a tuple:
def foo(*args):
for a in args:
print(a)
foo(1)
# 1
foo(1,2,3)
# 1
# 2
# 3
The **kwargs will give you all
keyword arguments except for those corresponding to a formal parameter as a dictionary.
def bar(**kwargs):
for a in kwargs:
print(a, kwargs[a])
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How to select rows from a DataFrame based on column values?
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10 Answers
10
Active
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How can I create a Set of Sets in Python?
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121
Python's complaining because the inner set objects are mutable and thus not hashable. The solu...
Float vs Decimal in ActiveRecord
...esent a Float. It's like a scientific notation for binary (something like +1.43*10^2). Because of that, it is impossible to store fractions and decimals in Float exactly.
That's why there is a Decimal format. If you do this:
irb:001:0> "%.47f" % (1.0/10)
=> "0.100000000000000005551115123125...
Could not locate Gemfile
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164
You do not have Gemfile in a directory where you run that command.
Gemfile is a file containin...