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Create an instance of a class from a string
Is there a way to create an instance of a class based on the fact I know the name of the class at runtime. Basically I would have the name of the class in a string.
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Bulk insert with SQLAlchemy ORM
...tly, we can produce an INSERT that is
competitive with using the raw database API directly.
Alternatively, the SQLAlchemy ORM offers the Bulk Operations suite of
methods, which provide hooks into subsections of the unit of work
process in order to emit Core-level INSERT and UPDATE constru...
Hash String via SHA-256 in Java
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@Sajjad Use your favorite base64 encoding function. I like the one in Apache Commons personally.
– Brendan Long
Oct 22 '13 at 19:34
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Abstract methods in Python [duplicate]
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Before abc was introduced you would see this frequently.
class Base(object):
def go(self):
raise NotImplementedError("Please Implement this method")
class Specialized(Base):
def go(self):
print "Consider me implemented"
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Differences between Java 8 Date Time API (java.time) and Joda-Time
...lds. A common feature of both field implementation design is that both are based on values of type long (no other types, not even enums).
Enum
JSR-310 offers enums like DayOfWeek or Month while Joda-Time does not offer this because it was mainly developed in years 2002-2004 before Java 5.
Zone AP...
Why are Docker container images so large?
...dependencies for what you installed. It is also important to note that the base images (like fedora:latest tend to be very bare-bones. You may be surprised by the number of dependencies your installed software has.
I was able to make your installation significantly smaller by adding yum -y clean al...
MySQL - UPDATE query based on SELECT Query
... check (from the same table) if there is an association between two events based on date-time.
11 Answers
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Selecting data frame rows based on partial string match in a column
I want to select rows from a data frame based on partial match of a string in a column, e.g. column 'x' contains the string "hsa". Using sqldf - if it had a like syntax - I would do something like:
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Deleting DataFrame row in Pandas based on column value
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If you want to delete rows based on multiple values of the column, you could use:
df[(df.line_race != 0) & (df.line_race != 10)]
To drop all rows with values 0 and 10 for line_race.
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What is the maximum value for an int32?
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If you think the value is too hard to remember in base 10, try base 2:
1111111111111111111111111111111
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answered Jun 1 '10 at...