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Finding ALL duplicate rows, including “elements with smaller subscripts”
...gt;% filter(n > 1) # data frame
df %>% add_count(col1, col2) %>% select(n) > 1 # logical vector
For duplicate rows (considering all columns):
df %>% group_by_all %>% add_tally %>% ungroup %>% filter(n > 1)
df %>% group_by_all %>% add_tally %>% ungroup %>% ...
Max return value if empty query
...oeSize = Workers.Where(x => x.CompanyId == 8)
.Select(x => x.ShoeSize)
.DefaultIfEmpty(0)
.Max();
The zero in DefaultIfEmpty is not necessary.
...
How can I recover the return value of a function passed to multiprocessing.Process?
... need to know which process is returning which value. If that what you actually need to know about the process, or do you need to correlate between your list of inputs and the list of outputs? In that case, I would recommend using multiprocessing.Pool.map to process your list of work items.
...
How to exclude property from Json Serialization
... { get; set; }
}
Or you can use DataContract and DataMember attribute to selectively serialize/deserialize properties/fields.
[DataContract]
public class Computer
{
// included in JSON
[DataMember]
public string Name { get; set; }
[DataMember]
public decimal SalePrice { get; set; }
/...
What are some (concrete) use-cases for metaclasses?
...a couple functions I found that I was able to increment the figure count, call draw manually, etc, but I needed to do these before and after every plotting call. So to create both an interactive plotting wrapper and an offscreen plotting wrapper, I found it was more efficient to do this via metacla...
What do all of Scala's symbolic operators mean?
...se of teaching, into four categories:
Keywords/reserved symbols
Automatically imported methods
Common methods
Syntactic sugars/composition
It is fortunate, then, that most categories are represented in the question:
-> // Automatically imported method
||= // Syntactic sugar
++= // Syn...
Eclipse: Error “.. overlaps the location of another project..” when trying to create new project
...r_src.
Right-click on the project explorer and import an existing project, select C:\Users\Martin\Java\Counter\ as your root directory. If Eclipse sees a project, you will be able to import it.
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What does (angle brackets) mean in Java?
...e a reference type. So you can't use primitive types like int or double or char or other primitive types.
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What is the purpose of the -m switch?
Could you explain to me what the difference is between calling
3 Answers
3
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Understanding the difference between __getattr__ and __getattribute__
...oesn't explicitly manage and do that via __getattr__ method.
Python will call this method whenever you request an attribute that hasn't already been defined, so you can define what to do with it.
A classic use case:
class A(dict):
def __getattr__(self, name):
return self[name]
a = A()...