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How can mixed data types (int, float, char, etc) be stored in an array?
...y elements a discriminated union, aka tagged union.
struct {
enum { is_int, is_float, is_char } type;
union {
int ival;
float fval;
char cval;
} val;
} my_array[10];
The type member is used to hold the choice of which member of the union is should be used for e...
Site stopped working in asp.net System.Web.WebPages.Razor.Configuration.HostSection cannot be cast t
...n the versions. Cheers!
<assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
<!--some more bidings-->
<dependentAssembly>
<assemblyIdentity name="System.Web.WebPages.Razor"
publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVer...
What is the difference between shallow copy, deepcopy and normal assignment operation?
... @grc But I have tried an example(I remove the new line here.) list_=[[1,2],[3,4]] newlist = list_.copy() list_[0]=[7,8] print(list_) print(newlist) The newlist still display [[1, 2], [3, 4]]. But list_[0] is a list which is mutable.
– Alston
Nov 12 '16...
Geometric Mean: is there a built-in?
...rough and @Gregor for making sure it works correctly.
I think some of the comments are related to a false-equivalency of NA values in the data and zeros. In the application I had in mind they are the same, but of course this is not generally true. Thus, if you want to include optional propagation o...
How much faster is Redis than mongoDB?
...is()
mongo = Connection().test
collection = mongo['test']
collection.ensure_index('key', unique=True)
def mongo_set(data):
for k, v in data.iteritems():
collection.insert({'key': k, 'value': v})
def mongo_get(data):
for k in data.iterkeys():
val = collection.find_one({'key'...
Why can't (or doesn't) the compiler optimize a predictable addition loop into a multiplication?
...
It does now -- at least, clang does:
long long add_100k_signed(int *data, int arraySize)
{
long long sum = 0;
for (int c = 0; c < arraySize; ++c)
if (data[c] >= 128)
for (int i = 0; i < 100000; ++i)
sum += data[c];
re...
Django Rest Framework File Upload
...h uploaded file
# ...
return Response(up_file.name, status.HTTP_201_CREATED)
urls.py
urlpatterns = patterns('',
url(r'^imageUpload', views.FileUploadView.as_view())
curl request to upload
curl -X POST -S -H -u "admin:password" -F "file=@img.jpg;type=image/jpg" 127.0.0.1:8000/r...
What is the worst gotcha in C# or .NET? [closed]
...efixes for your private fields (there are others, but this is a good one): _myVar, m_myVar
– jrista
Jun 26 '09 at 8:01
205
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An error occurred while installing pg (0.17.1), and Bundler cannot continue
...
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181
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Group by multiple columns in dplyr, using string vector input
...oup_by_at(vars(one_of(columns))) %>%
summarize(Value = mean(value))
#compare plyr for reference
df2 <- plyr::ddply(data, columns, plyr::summarize, value=mean(value))
table(df1 == df2, useNA = 'ifany')
## TRUE
## 27
The output from your example question is as expected (see comparison to...