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Repeat each row of data.frame the number of times specified in a column
...q(nrow(df)), df$freq), 1:2]
The code for data.table is a tad cleaner:
# convert to data.table by reference
setDT(df)
df.expanded <- df[rep(seq(.N), freq), !"freq"]
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About catching ANY exception
...{0}): {1}".format(errno, strerror)
except ValueError:
print "Could not convert data to an integer."
except:
print "Unexpected error:", sys.exc_info()[0]
raise
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How does the Windows Command Interpreter (CMD.EXE) parse scripts?
...le scanning for a :label, <Ctrl-Z>, is treated as itself - it is not converted to <LF>
Phase 1) Percent Expansion:
A double %% is replaced by a single %
Expansion of arguments (%*, %1, %2, etc.)
Expansion of %var%, if var does not exist replace it with nothing
Line is truncated at fi...
How do I view the SQL generated by the Entity Framework?
... with EF6, I could get it only with reflection. but first, I had to convert result to System.Data.Entity.Infrastructure.DbQuery<T>, then get internal property InternalQuery as (System.Data.Entity.Internal.Linq.InternalQuery<T>), and only then, use ToTraceString()
...
How do you get a string from a MemoryStream?
...
Using a StreamReader to convert the MemoryStream to a String.
<Extension()> _
Public Function ReadAll(ByVal memStream As MemoryStream) As String
' Reset the stream otherwise you will just get an empty string.
' Remember the position s...
Decompressing GZip Stream from HTTPClient Response
...d JSON
response = client.GetAsync(url).Result;
//converts JSON to string
string responseJSONContent = response.Content.ReadAsStringAsync().Result;
//deserializes string to list
var jsonList = DeSerializeJsonString(responseJSONContent);
...
How to compare DateTime in C#?
...
you can convert datetime to string
– Dieu Phan Dinh
Nov 21 '16 at 8:24
...
Python - Create list with numbers between 2 values?
..., 12, 13, 14, 15, 16]
In Python 3.x range is a iterator. So, you need to convert it to a list:
>>> list(range(11, 17))
[11, 12, 13, 14, 15, 16]
Note: The second number is exclusive. So, here it needs to be 16+1 = 17
EDIT:
To respond to the question about incrementing by 0.5, the easi...
Difference between assertEquals and assertSame in phpunit?
...even thinks that '0012' == '12'. Even if both values are strings, they are converted to integers for the comparison! You should really use assertSame whenever you can.
– marco-fiset
Jun 28 '13 at 13:23
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Why should casting be avoided? [closed]
...ion's pretty simple (at least IMO): a cast (obviously enough) means you're converting something from one type to another. When/if you do that, it raises the question "Why?" If you really want something to be a particular type, why didn't you define it to be that type to start with? That's not to say...