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Why declare a struct that only contains an array in C?
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It allows you to pass the array to a function by value, or get it returned by value from a function.
Structs can be passed by value, unlike arrays which decay to a pointer in these contexts.
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How to Convert all strings in List to lower case using LINQ?
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Easiest approach:
myList = myList.ConvertAll(d => d.ToLower());
Not too much different than your example code. ForEach loops the original list whereas ConvertAll creates a new one which you need to reassign.
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Create a dictionary on a list with grouping
...vert it to a dictionary, as follows:
Dim qry = (From acs In ActualSales _
Group By acs.ProductID Into Group _
Select ProductID, Months = Group.ToDictionary(Function(c) c.Period) _
).ToDictionary(Function(c) c.ProductID)
The resulting query can be used as fo...
Efficient evaluation of a function at every cell of a NumPy array
...t be faster than the "manual" double loop iteration and assignment through all the array elements. Especially, because it stores the result to a newly created variable (and not directly to the initial input). Thanks a lot for your reply though:)
– Peter
Oct 9 '...
SQL- Ignore case while searching for a string
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Use something like this -
SELECT DISTINCT COL_NAME FROM myTable WHERE UPPER(COL_NAME) LIKE UPPER('%PriceOrder%')
or
SELECT DISTINCT COL_NAME FROM myTable WHERE LOWER(COL_NAME) LIKE LOWER('%PriceOrder%')
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How to read the database table name of a Model instance?
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Found the answer myself: the _meta attribute of an instance has the information:
model_instance._meta.db_table
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What is the difference between .text, .value, and .value2?
...presenting what is displayed on the screen for the cell. Using .Text is usually a bad idea because you could get ####
.Value2 gives you the underlying value of the cell (could be empty, string, error, number (double) or boolean)
.Value gives you the same as .Value2 except if the cell was formatted...
Can dplyr package be used for conditional mutating?
...and the conditions (except for the default value of NA at the end) are mutually exclusive, as is the case in the question, then we can use an arithmetic expression such that each term is multiplied by the desired result using na_if at the end to replace 0 with NA.
df %>%
mutate(g = 2 * (a == 2 ...
Scala @ operator
...n itself? That would be accomplished with this:
o match {
case x @ Some(_) => println(x)
case None =>
}
Note that @ can be used at any level, not just at the top level of the matching.
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How does the const constructor actually work?
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Const constructor creates a "canonicalized" instance.
That is, all constant expressions begin canonicalized, and later these "canonicalized" symbols are used to recognize equivalence of these constants.
Canonicalization:
A process for converting data that has more than one possible rep...