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What is the “right” way to iterate through an array in Ruby?
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This will iterate through all the elements giving you the value and the index:
array = ["A", "B", "C"]
array.each_with_index {|val, index| puts "#{val} => #{index}" }
Prints:
A => 0
B => 1
C => 2
I'm not quite sure from your question which one you are looking for.
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Find integer index of rows with NaN in pandas dataframe
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For DataFrame df:
import numpy as np
index = df['b'].index[df['b'].apply(np.isnan)]
will give you back the MultiIndex that you can use to index back into df, e.g.:
df['a'].ix[index[0]]
>>> 1.452354
For the integer index:
df_index = df.index.values...
Pandas - Get first row value of a given column
...ow for an explanation of why. Because a subtle difference in
the order of indexing makes a big difference in behavior, it is better to use single indexing assignment:
df.iloc[0, df.columns.get_loc('Btime')] = x
df.iloc[0, df.columns.get_loc('Btime')] = x (recommended):
The recommended way to ...
How to print pandas DataFrame without index
I want to print the whole dataframe, but I don't want to print the index
8 Answers
8
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Set selected index of an Android RadioGroup
Is there a way to set the selected index of a RadioGroup in android, other than looping through the child radiobuttons and selecting checking the radio button at the selected index?
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Setting unique Constraint with fluent API?
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On EF6.2, you can use HasIndex() to add indexes for migration through fluent API.
https://github.com/aspnet/EntityFramework6/issues/274
Example
modelBuilder
.Entity<User>()
.HasIndex(u => u.Email)
.IsUnique();
On EF6.1 o...
Create an index on a huge MySQL production table without table locking
I need to create an index on a ~5M rows MySQL table. It is a production table, and I fear a complete block of everything if I run a CREATE INDEX statement...
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Multiple columns index when using the declarative ORM extension of sqlalchemy
... the sqlalchemy.Column class, we should use the class sqlalchemy.schema.Index to specify an index that contains multiple columns.
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deny directory listing with htaccess
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Options -Indexes should work to prevent directory listings.
If you are using a .htaccess file make sure you have at least the "allowoverride options" setting in your main apache config file.
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Array extension to remove object by value
However, I get an error on var index = find(self, object)
15 Answers
15
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