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data.frame rows to a list
...es of xy.df to be the names of the output list, you can do:
xy.list <- setNames(split(xy.df, seq(nrow(xy.df))), rownames(xy.df))
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How do I use boolean variables in Perl?
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8 Answers
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efficient circular buffer?
...larlist(4, [1, 2, 3, 4, 5]) # [2, 3, 4, 5] (4 items)
circularlist(4, set([1, 2, 3, 4, 5])) # [2, 3, 4, 5] (4 items)
circularlist(4, (1, 2, 3, 4, 5)) # [2, 3, 4, 5] (4 items)
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How can I transform string to UTF-8 in C#?
...database field structure i phpmyadmin [ or any other control panel] should set to utf8-gerneral-ci
2) you should change your string [Ex. textbox1.text] to byte, therefor
2-1) define byte[] st2;
2-2) convert your string [textbox1.text] to unicode [ mmultibyte string] by :
byte[] st2 = System.Te...
How do I check if an integer is even or odd? [closed]
How can I check if a given number is even or odd in C?
31 Answers
31
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How to repeat a string a variable number of times in C++?
I want to insert 'n' spaces (or any string) at the beginning of a string in C++. Is there any direct way to do this using either std::strings or char* strings?
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When to Redis? When to MongoDB? [closed]
...ased on your data.
Redis provides a bunch of useful data structures (e.g. Sets, Hashes, Lists), but you have to explicitly define how you want to store you data. To put it in a nutshell, Redis and MongoDB can be used in order to achieve similar things. Redis is simply faster, but not suited for pro...
What is the most efficient way to create a dictionary of two pandas Dataframe columns?
...und a faster way to solve the problem, at least on realistically large datasets using:
df.set_index(KEY).to_dict()[VALUE]
Proof on 50,000 rows:
df = pd.DataFrame(np.random.randint(32, 120, 100000).reshape(50000,2),columns=list('AB'))
df['A'] = df['A'].apply(chr)
%timeit dict(zip(df.A,df.B))
%time...
How to get the nth element of a python list or a default if not available
I'm looking for an equivalent in python of dictionary.get(key, default) for lists. Is there any one liner idiom to get the nth element of a list or a default value if not available?
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Double vs single quotes
I'm really new to Ruby and I'm trying to understand if there's a specific time when I should use "" vs '' .
8 Answers
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