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Fatal error: unexpectedly found nil while unwrapping an Optional values [duplicate]
...e is first set. In these cases, it
is useful to remove the need to check and unwrap the optional’s value
every time it is accessed, because it can be safely assumed to have a
value all of the time.
These kinds of optionals are defined as implicitly unwrapped
optionals. You write an im...
How can I pad a String in Java?
...
Apache StringUtils has several methods: leftPad, rightPad, center and repeat.
But please note that — as others have mentioned and demonstrated in this answer — String.format() and the Formatter classes in the JDK are better options. Use them over the commons code.
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Access Enum value using EL with JSTL
...nswered Dec 15 '08 at 14:27
Alexander VasiljevAlexander Vasiljev
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Pandas percentage of total with groupby
...calculate the percentage in a simpler way -- just groupby the state_office and divide the sales column by its sum. Copying the beginning of Paul H's answer:
# From Paul H
import numpy as np
import pandas as pd
np.random.seed(0)
df = pd.DataFrame({'state': ['CA', 'WA', 'CO', 'AZ'] * 3,
...
Error when deploying an artifact in Nexus
...version, proxy repo or group instead of a hosted repository)
Check those and if you still run into trouble provide more details here.
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Unioning two tables with different number of columns
I have two tables (Table A and Table B).
5 Answers
5
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differences between 2 JUnit Assert classes
...t framework contains 2 Assert classes (in different packages, obviously) and the methods on each appear to be very similar. Can anybody explain why this is?
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How do I set a column value to NULL in SQL Server Management Studio?
How do I clear the value from a cell and make it NULL?
6 Answers
6
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How do you work with an array of jQuery Deferreds?
...then the schemas, then finally initialize the application with the schemas and urls for the various data objects. As the user navigates the application, data objects are loaded, validated against the schema, and displayed. As the user CRUDs the data, the schemas provide first-pass validation.
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Web scraping with Python [closed]
...s = row('td')
print tds[0].string, tds[1].string
# will print date and sunrise
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