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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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Which characters make a URL invalid?
...racters) may contain any of the following 84 characters:
ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-._~:/?#[]@!$&'()*+,;=
Note that this list doesn't state where in the URI these characters may occur.
Any other character needs to be encoded with the percent-encoding (%hh...
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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How to send an email from JavaScript
...;
if (rq) {
// Success; attempt to use an Ajax request to a PHP script to send the e-mail
try {
rq.open('GET', 'sendmail.php?to=' + encodeURIComponent(to) + '&subject=' + encodeURIComponent(subject) + '&d=' + new Date().getTime().toString(), true);
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how to show alternate image if source image is not found? (onerror working in IE but not in mozilla)
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If you're open to a PHP solution:
<td><img src='<?PHP
$path1 = "path/to/your/image.jpg";
$path2 = "alternate/path/to/another/image.jpg";
echo file_exists($path1) ? $path1 : $path2;
?>' alt='' />
</td>
////EDI...
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...
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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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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