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Python memoising/deferred lookup property decorator
...nce, but they're a real bottleneck to calculate that first time and only really accessed for special cases. Hence they can also be cached after they've been retrieved from the database (this therefore fits the definition of memoisation where the input is simply "no input").
...
How to set environment variables in Python?
I need to set some environment variables in the Python script and I want all the other scripts that are called from Python to see the environment variables' set.
...
When I catch an exception, how do I get the type, file, and line number?
...Error:
print(traceback.format_exc())
Output
Traceback (most recent call last):
File "/path/to/file.py", line 51, in <module>
print(4/0)
ZeroDivisionError: division by zero
Process finished with exit code 0
...
Python string class like StringBuilder in C#?
...
There is no one-to-one correlation. For a really good article please see Efficient String Concatenation in Python:
Building long strings in the Python
progamming language can sometimes
result in very slow running code. In
this article I investigate the
comp...
How to set child process' environment variable in Makefile
...
I have GNU make 3.81, and all: <\n\t>export PROJ_ROOT=$(CURDIR)<\n\t>echo $(PROJ_ROOT)<\n> outputs the correct expansion for the first row, but only echo for the second one. PROJ_ROOT is not set after running make. Spaces around = gi...
Duplicate symbols for architecture x86_64 under Xcode
...at defines an Objective-C class or category. While this option will
typically result in a larger executable (due to additional object code
loaded into the application), it will allow the successful creation of
effective Objective-C static libraries that contain categories on
existing classes...
How do I use IValidatableObject?
... Prop1 = 1,
Prop2 = 2
};
bool validateAllProperties = false;
var results = new List<ValidationResult>();
bool isValid = Validator.TryValidateObject(
toValidate,
new ValidationContext(toValidate, null, null),
...
ImportError: Cannot import name X
...r different files named: main, vector, entity and physics. I will not post all the code, just the imports, because I think that's where the error is. (If you want, I can post more)
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Determine the type of an object?
...object, and isinstance() to check an object’s type against something. Usually, you want to use isistance() most of the times since it is very robust and also supports type inheritance.
To get the actual type of an object, you use the built-in type() function. Passing an object as the only param...
Multiple linear regression in Python
...as some other model evaluation criteria. If you want the stuff like in Akavall's answer, statsmodels has some more R-like diagnostics.
– djs
Mar 17 '16 at 18:56
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