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Pandas: create two new columns in a dataframe with values calculated from a pre-existing column
...pply is generally not much faster than iterating over a Python list. Let's test the performance of a for-loop to do the same thing as above
%%timeit
A1, A2 = [], []
for val in df['a']:
A1.append(val**2)
A2.append(val**3)
df['A1'] = A1
df['A2'] = A2
298 ms ± 7.14 ms per loop (mean ± std....
How to select rows with one or more nulls from a pandas DataFrame without listing columns explicitly
...y verbose, but functional.
import pandas as pd
import numpy as np
# Some test data frame
df = pd.DataFrame({'num_legs': [2, 4, np.nan, 0, np.nan],
'num_wings': [2, 0, np.nan, 0, 9],
'num_specimen_seen': [10, np.nan, 1, 8, np.nan]...
Bootstrap combining rows (rowspan)
I am testing Twitter Bootstrap and got stuck with
basic scaffolding with rows. I revisited their documentation number of times and I can see nesting columns where you can basically nest columns within a column but I cannot locate
the capability of combining rows into one and have it aligned with ...
How to vertically center a container in Bootstrap?
...line example.
In some of old web browsers such as Firefox 9 (in which I've tested), the flex container - .vertical-center in this case - won't take the available space inside the parent, therefore we need to specify the width property like: width: 100%.
Also in some of web browsers as mentioned abov...
XSD - how to allow elements in any order any number of times?
...hild1>2</child1>
<child1>3</child1>
<child2>test</child2>
<child2>another-test</child2>
</foo>
Which seems to match your question.
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Why is a round-trip conversion via a string not safe for a double?
...t;sPositiveInfinity);
goto lExit;
}
NumberToDouble(&number, &dTest);
if (dTest == value) {
gc.refRetVal = NumberToString(&number, 'G', DOUBLE_PRECISION, gc.numfmt);
goto lExit;
}
DoubleToNumber(value, 17, &number);
DoubleToNumber is pretty simple -- it just calls _ec...
How to align checkboxes and their labels consistently cross-browsers
...ems to be failing to do that since 2013).
After over an hour of tweaking, testing, and trying different styles of markup, I think I may have a decent solution. The requirements for this particular project were:
Inputs must be on their own line.
Checkbox inputs need to align vertically with the la...
Reading/writing an INI file
...
using INI;
Create a INIFile like this
INIFile ini = new INIFile("C:\\test.ini");
Use IniWriteValue to write a new value to a specific key in a section or use IniReadValue to read a value FROM a key in a specific Section.
Note: if you're beginning from scratch, you could read this MSDN artic...
Converting JSON String to Dictionary Not List
..." double quotes rather then ' single quotes.
Your JSON dump.txt File:
{"test":"1", "test2":123}
Python Script:
import json
with open('/your/path/to/a/dict/dump.txt') as handle:
dictdump = json.loads(handle.read())
...
How to remove all debug logging calls before building the release version of an Android app?
...umbers in stacktraces. It won't always be out of sync (I did several quick tests but can't exactly pinpoint what the cause is, possibly if you concatenate a string in the Log call), but sometimes it will be a few lines off. Worth the trouble IMO for the ability to easily remove Log calls.
...