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How to group dataframe rows into list in pandas groupby?
...me: b, dtype: object
In [3]: df1 = df.groupby('a')['b'].apply(list).reset_index(name='new')
df1
Out[3]:
a new
0 A [1, 2]
1 B [5, 5, 4]
2 C [6]
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Android - Set max length of logcat messages
... while (!print.isEmpty()) {
int lastNewLine = print.lastIndexOf('\n', ENTRY_MAX_LEN);
int nextEnd = lastNewLine != -1 ? lastNewLine : Math.min(ENTRY_MAX_LEN, print.length());
String next = print.substring(0, nextEnd /*exclusive*/);
a...
Having issue with multiple controllers of the same name in my project
...n}/{id}", // URL with parameters
new { controller = "Home", action = "Index", id = UrlParameter.Optional }, // Parameter defaults
new string[] { "MyCompany.MyProject.WebMvc.Controllers"}
);
This will make http://server/ go to your HomeController's Index action which is, I think, what you...
A std::map that keep track of the order of insertion?
...rt via std::sort using appropriate functor.
Or you could use boost::multi_index. It allows to use several indexes.
In your case it could look like the following:
struct value_t {
string s;
int i;
};
struct string_tag {};
typedef multi_index_container<
value_t,
indexed_by&...
OPTION (RECOMPILE) is Always Faster; Why?
...ge and distribution of the types of values in various column on tables and indexes. This helps the query engine to develop a "Plan" of attack for how it will do the query, for example the type of method it will use to match keys between tables using a hash or looking through the entire set. You can ...
How to write to an existing excel file without overwriting data (using pandas)?
... if truncate_sheet and sheet_name in writer.book.sheetnames:
# index of [sheet_name] sheet
idx = writer.book.sheetnames.index(sheet_name)
# remove [sheet_name]
writer.book.remove(writer.book.worksheets[idx])
# create an empty sheet [sheet_n...
Iteration over std::vector: unsigned vs signed index variable
...ou should prefer iterators. Some people tell you to use std::size_t as the index variable type. However, that is not portable. Always use the size_type typedef of the container (While you could get away with only a conversion in the forward iterating case, it could actually go wrong all the way in t...
How to sort a list/tuple of lists/tuples by the element at a given index?
...s tup, or t, or whatever you like and it'll still work. tup here specifies index of the list's tuple, so 1 means that sorting will be performed by the second values of tuples from the original list (2, 5, 8).
– Neurotransmitter
Jul 26 '16 at 15:13
...
Why is using “for…in” for array iteration a bad idea?
...y.
for (var i = 0; i < a.length; i++) {
// Iterate over numeric indexes from 0 to 5, as everyone expects.
console.log(a[i]);
}
/* Will display:
undefined
undefined
undefined
undefined
undefined
5
*/
can sometimes be totally different from the other...
Does Java SE 8 have Pairs or Tuples?
...round with lazy functional operations in Java SE 8, and I want to map an index i to a pair / tuple (i, value[i]) , then filter based on the second value[i] element, and finally output just the indices.
...