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Why doesn't Python have a sign function?
... it wasn't accepted, because they didn't agree on what it should return in all the edge cases (+/-0, +/-nan, etc)
So they decided to implement only copysign, which (although more verbose) can be used to delegate to the end user the desired behavior for edge cases - which sometimes might require the...
Access multiple elements of list knowing their index
...3, 8, 5, 6])
b = [1, 2, 5]
print(list(a[b]))
# Result:
[1, 5, 5]
But really, your current solution is fine. It's probably the neatest out of all of them.
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How to print a query string with parameter values when using Hibernate
...he the following categories:
org.hibernate.SQL - set to debug to log all SQL DML statements as they are executed
org.hibernate.type - set to trace to log all JDBC parameters
So a log4j configuration could look like:
# logs the SQL statements
log4j.logger.org.hibernate.SQL=debug
# Logs the...
What does extern inline do?
...e, static inline, and extern inline constructs; most pre-C99 compiler generally follow its lead.
GNU89:
inline: the function may be inlined (it's just a hint though). An out-of-line version is always emitted and externally visible. Hence you can only have such an inline defined in one compilatio...
Entity Attribute Value Database vs. strict Relational Model Ecommerce
...l entities "properly", but add "extensions" for custom attributes for some/all entities)
Pro/Con: more time required to gather requirements and design than option 1 but perhaps not as much as option 2 *
Con: new entities must be modelled and designed by a professional
Pro: new attributes might be ...
File Upload ASP.NET MVC 3.0
...maxRequestLength="x" /> in your web.config, where x is the number of KB allowed for upload.
– rsbarro
May 22 '11 at 20:33
86
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Scala type programming resources
...programming, the computation occurs at compile time. I will try to draw parallels between programming at the value-level and programming at the type-level.
Paradigms
There are two main paradigms in type-level programming: "object-oriented" and "functional". Most examples linked to from here follow...
Flask-SQLAlchemy import/context issue
...:
# fields here
pass
And then in your application setup you can call init_app:
# apps.application.py
from flask import Flask
from apps.members.models import db
app = Flask(__name__)
# later on
db.init_app(app)
This way you can avoid cyclical imports.
This pattern does not necessitate ...
Resolve build errors due to circular dependency amongst classes
...ember that the .cc and not the .h is the unit of compilation), you need to allocate space for object A. So, well, how much space then? Enough to store B! What's the size of B then? Enough to store A! Oops.
Clearly a circular reference that you must break.
You can break it by allowing the compiler ...
What does “hashable” mean in Python?
...y and a set member, because these data structures use the hash value internally.
All of Python’s immutable built-in objects are hashable, while no mutable containers (such as lists or dictionaries) are. Objects which are instances of user-defined classes are hashable by default; they all comp...