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Why would finding a type's initializer throw a NullReferenceException?
....cs:
(196c.1874): Access violation - code c0000005 (first chance)
mscorlib_ni!System.RuntimeType.GetConstructorImpl(System.Reflection.BindingFlags, System.Reflection.Binder, System.Reflection.CallingConventions, System.Type[], System.Reflection.ParameterModifier[])+0xa3:
000007fe`e5735403 488b4608 ...
Convert unix time to readable date in pandas dataframe
...12.15
3 1349979305 12.19
4 1350065705 12.15
In [25]: df['date'] = pd.to_datetime(df['date'],unit='s')
In [26]: df.head()
Out[26]:
date price
0 2012-10-08 18:15:05 12.08
1 2012-10-09 18:15:05 12.35
2 2012-10-10 18:15:05 12.15
3 2012-10-11 18:15:05 12.19
4 2012-10-12 18:15:...
Check if event exists on element [duplicate]
... $.data() is not working any more in jQuery >= 1.8. For me $._data() is working in jQuery 1.10.1. See answer of Tom Gerken for a working solution.
– jbandi
Aug 27 '13 at 21:21
...
Retain cycle on `self` with blocks
...sue is identical to the workaround for the retain issue; namely, using the __block storage class for the variable.
In any case, to answer your question, there's no real alternative here. If you're designing your own block-based API, and it makes sense to do so, you could have the block get passed t...
Is there a Python equivalent of the C# null-coalescing operator?
...instance of a class or None (as long as your class does not define members __nonzero__() and __len__()), it is secure to use the same semantics as the null-coalescing operator.
In fact, it may even be useful to have this side-effect of Python. Since you know what values evaluates to false, you can ...
How can I quantify difference between two images?
...ead images as 2D arrays (convert to grayscale for simplicity)
img1 = to_grayscale(imread(file1).astype(float))
img2 = to_grayscale(imread(file2).astype(float))
# compare
n_m, n_0 = compare_images(img1, img2)
print "Manhattan norm:", n_m, "/ per pixel:", n_m/img1.size
print "Z...
g++ undefined reference to typeinfo
...no-rtti and -frtti code. Then you need to ensure that any class, which type_info is accessed in the -frtti code, have their key method compiled with -frtti. Such access can happen when you create an object of the class, use dynamic_cast etc.
[source]
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ASP.NET MVC - Attaching an entity of type 'MODELNAME' failed because another entity of the same type
... only fields except entity id worked fine: var entity = context.Find(entity_id); entity.someProperty = newValue; context.Entry(entity).Property(x => x.someProperty).IsModified = true; context.SaveChanges();
– Anton Lyhin
Dec 10 '15 at 22:34
...
How can I add a key/value pair to a JavaScript object?
...ush(). For more info check the docs, they have some great examples there.
_.merge (Lodash only)
The second object will overwrite or add to the base object.
undefined values are not copied.
var obj = {key1: "value1", key2: "value2"};
var obj2 = {key2:"value4", key3: "value3", key4: undefined};
_.m...
Why do I get a segmentation fault when writing to a “char *s” initialized with a string literal, but
...the pointer to void * as in printf("%p", (void *)str); When printing a size_t with printf, you should use "%zu" if using the latest C standard (C99).
– Chris Young
Oct 3 '08 at 7:44
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