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How to Calculate Execution Time of a Code Snippet in C++
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You can use this function I wrote. You call GetTimeMs64(), and it returns the number of milliseconds elapsed since the unix epoch using the system clock - the just like time(NULL), except in milliseconds.
It works on both windows and linux; it is thread safe.
Not...
How are GCC and g++ bootstrapped?
...ilt
(optional) repeat step 2 for verification purposes.
This process is called bootstrapping. It tests the compiler's capability of compiling itself and makes sure that the resulting compiler is built with all the optimizations that it itself implements.
EDIT: Drew Dormann, in the comments, point...
Adding a column to a data.frame
...number of groups (x in mapply) and its length (y in mapply)
mytb<-read.table(text="h_no h_freq h_freqsq group
1 0.09091 0.008264628 1
2 0.00000 0.000000000 1
3 0.04545 0.002065702 1
4 0.00000 0.000000000 1
1 0.13636 0.018594050 2
2 0.00000 0.000000000 2
3 0.00000 ...
What is the difference between BIT and TINYINT in MySQL?
...thing on linux, I had problems with queries that inserted or selected from tables that had BIT DATA TYPE.
Bit is not safe for now.
I changed to tinyint(1) and worked perfectly. I mean that you only need a value to diferentiate if it's 1 or 0 and tinyint(1) it's ok for that
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Is there any difference between “foo is None” and “foo == None”?
... Hmmm, I think your link changed, unless you were interested in how to call external functions from python
– Pat
May 4 '12 at 20:39
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How to make rounded percentages add up to 100%
...55310199789695, 8.780231335436383, 8.04416403785489, 0]. The last one logically returns -1. I thought of the following solution really quickly but there's probably something better: jsfiddle.net/0o75bw43/1
– Cruclax
Aug 5 '16 at 16:39
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nullable object must have a value
...checking for null in your lambda.
Example:
MyEnum? type = null;
Entities.Table.Where(a => type == null ||
a.type == (int)type).ToArray(); // Exception: Nullable object must have a value
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Can I add a custom attribute to an HTML tag?
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There is a good table of different doctypes and corresponding browser modes here: hsivonen.fi/doctype/#handling. HTML5 doctype switches all post-2001 browsers into (Full) Standards mode. XHTML Transitional and HTML 4 Transitional (especially...
Python string.join(list) on object array rather than string array
...riments says that the list comprehension one can be a good 60% faster on small lists (experiment run 10^6 times on a list of three object()s). However, their performance is similar on big lists (2nd experiment run once on a 10^7 objects() list).
– gozzilli
Mar ...
django admin - add custom form fields that are not part of the model
... ModelForm class and then declare your extra fields inside that as you normally would. I've also given an example of how you might use these values in form.save():
from django import forms
from yourapp.models import YourModel
class YourModelForm(forms.ModelForm):
extra_field = forms.CharFiel...