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type object 'datetime.datetime' has no attribute 'datetime'
...
Datetime is a module that allows for handling of dates, times and datetimes (all of which are datatypes). This means that datetime is both a top-level module as well as being a type within that module. This is confusing.
Your error is probably based ...
How to add an empty column to a dataframe?
... with .reindex(rows=[...]). Note that newer versions of Pandas (v>0.20) allow you to specify an axis keyword rather than explicitly assigning to columns or rows.
Here is an example adding multiple columns:
mydf = mydf.reindex(columns = mydf.columns.tolist() + ['newcol1','newcol2'])
or
mydf...
Convert int to char in java
...a + '0');
System.out.println(b);
Here, we used '0' because chars are actually represented by ASCII values. '0' is a char and represented by the value of 48.
We typed (a + '0') and in order to add these up, Java converted '0' to its ASCII value which is 48 and a is 1 so the sum is 49. Then what w...
Can a recursive function be inline?
...torial(x3 - 1);
}
}
}
}
In this case, we've basically inlined the function 3 times. Some compilers do perform this optimization. I recall MSVC++ having a setting to tune the level of inlining that would be performed on recursive functions (up to 20, I believe).
...
Generate a random number in the range 1 - 10
... in: ERROR: operator does not exist: date + double precision Does trunc really return integers?
– Bogdan Gusiev
Jan 26 '10 at 12:44
3
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Case-insensitive search in Rails model
...Aug 13 '15 at 20:41
Andrew Marshall
87.3k1818 gold badges202202 silver badges204204 bronze badges
answered Feb 8 '10 at 9:35
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if (key in object) or if(object.hasOwnProperty(key)
...type
If we want to check that some property exist on the prototype, logically, we would say:
console.log(('name' in o) && !o.hasOwnProperty('name')); //false
console.log(('gender' in o) && !o.hasOwnProperty('gender')); //true - it's in prototype
Finally:
So, regarding to statem...
How to select the row with the maximum value in each group
...ata.table) ## 1.9.2
group <- as.data.table(group)
If you want to keep all the entries corresponding to max values of pt within each group:
group[group[, .I[pt == max(pt)], by=Subject]$V1]
# Subject pt Event
# 1: 1 5 2
# 2: 2 17 2
# 3: 3 5 2
If you'd like ju...
AWS S3: The bucket you are attempting to access must be addressed using the specified endpoint
...ting to access must be addressed using the specified endpoint. Please send all future requests to this endpoint."
US Standard is us-east-1
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How do I fix "The expression of type List needs unchecked conversion…'?
...);
for(Object o: c)
r.add(clazz.cast(o));
return r;
}
This allows you to do:
List<SyndEntry> entries = castList(SyndEntry.class, sf.getEntries());
Because this solution checks that the elements indeed have the correct element type by means of a cast, it is safe, and does not...