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Checking if a string can be converted to float in Python
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Understanding exactly when a data.table is a reference to (vs a copy of) another data.table
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Yes, it's subassignment in R using <- (or = or ->) that makes a copy of the whole object...
In c# is there a method to find the max of 3 numbers?
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Check number of arguments passed to a Bash script
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Aggregate / summarize multiple variables per group (e.g. sum, mean)
...he reshape2 package for this task:
require(reshape2)
df_melt <- melt(df1, id = c("date", "year", "month"))
dcast(df_melt, year + month ~ variable, sum)
# year month x1 x2
1 2000 1 -80.83405 -224.9540159
2 2000 2 -223.76331 -288.2418017
3 2000 3 -188.83930 -481....
Find object in list that has attribute equal to some value (that meets any condition)
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Tropicalrambler
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answered Aug 19 '11 at 18:01
agfagf
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How to make lists contain only distinct element in Python? [duplicate]
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What's the cleanest way of applying map() to a dictionary in Swift?
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How do I get java logging output to appear on a single line?
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Creating a Pandas DataFrame from a Numpy array: How do I specify the index column and column headers
...umns to DataFrame constructor, as in:
>>> pd.DataFrame(data=data[1:,1:], # values
... index=data[1:,0], # 1st column as index
... columns=data[0,1:]) # 1st row as the column names
edit: as in the @joris comment, you may need to change above to np.int_(dat...