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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...
Implode an array with JavaScript?
...ore the imploded array):
var tmp = "";
$.each(output_saved_json, function(index,value) {
tmp = tmp + output_saved_json[index] + ";";
});
output_saved_json = tmp.substring(0,tmp.length - 1); // remove last ";" added
I have used substring to remove last ";" added at the final without necessity...
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&...
Compiler Ambiguous invocation error - anonymous method and method group with Func or Action
...mpatibility relationship between methods and delegate types, but this is a question of convertibility of method groups and delegate types, which is different.
Now that we've got that out of the way, we can walk through section 6.6 of the spec and see what we get.
To do overload resolution we need ...
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...
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...