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Determining complexity for recursive functions (Big O notation)
...he time complexity, in Big O notation, for each function:
int recursiveFun1(int n)
{
if (n <= 0)
return 1;
else
return 1 + recursiveFun1(n-1);
}
This function is being called recursively n times before reaching the base case so its O(n), often called linear.
int recursi...
Why does 1==1==1 return true, “1”==“1”==“1” return true, and “a...
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Because you are comparing the (boolean) result of the first equality with the (non-boolean) th...
Dynamically update values of a chartjs chart
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SQL RANK() versus ROW_NUMBER()
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ROW_NUMBER : Returns a unique number for each row starting with 1. For rows that have duplicate values,numbers are arbitarily assigned.
Rank : Assigns a unique number for each row starting with 1,except for rows that have duplicate values,in which case the same ranking is assigned and a ...
What's the fastest way to merge/join data.frames in R?
...In particular it never looks for duplicate keys. (continued after code)
DF1 = data.frame(a = c(1, 1, 2, 2), b = 1:4)
DF2 = data.frame(b = c(1, 2, 3, 3, 4), c = letters[1:5])
merge(DF1, DF2)
b a c
1 1 1 a
2 2 1 b
3 3 2 c
4 3 2 d
5 4 2 e
DF1$c = DF2$c[match(DF1$b, DF2$b)]
DF1$c
[1] a b ...
Applying a function to every row of a table using dplyr?
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edited Aug 6 '19 at 3:20
answered Jul 14 '14 at 0:20
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What's the best way to get the last element of an array without deleting it?
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get list from pandas dataframe column
... cast it with list(x).
import pandas as pd
data_dict = {'one': pd.Series([1, 2, 3], index=['a', 'b', 'c']),
'two': pd.Series([1, 2, 3, 4], index=['a', 'b', 'c', 'd'])}
df = pd.DataFrame(data_dict)
print(f"DataFrame:\n{df}\n")
print(f"column types:\n{df.dtypes}")
col_one_list = df['o...