大约有 828 项符合查询结果（耗时：0.0302秒） [XML]
How to check whether a pandas DataFrame is empty?
...ength of a dataframe's columns index:
if len(df.columns) == 0: 1
Reason:
According to the Pandas Reference API, there is a distinction between:
an empty dataframe with 0 rows and 0 columns
an empty dataframe with rows containing NaN hence at least 1 column
Arguably, they are not the same. The oth...
The $.param( ) inverse function in JavaScript / jQuery
... answered Jun 9 '11 at 19:23
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Comparison of CI Servers? [closed]
...
confluence.public.thoughtworks.org/display/CC/CI+Feature+Matrix not found
– Kiquenet
Jun 23 '14 at 9:58
11
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case-insensitive list sorting, without lowercasing the result?
... then have to use unicode.lower for unicode objects, whereas string.lower accepts both (which, as you put it, is probably not really a "sane" mode of operation, though).
– Daniel Andersson
Jun 5 '16 at 10:29
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How to make a background 20% transparent on Android
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Make the color have 80% in the alpha channel. For example, for red use #CCFF0000:
<TextView
...
android:background="#CCFF0000" />
In the example, CC is the hexadecimal number for 255 * 0.8 = 204. Note that the first two hexadecimal digits are for the alpha channel. The format is #A...
Python: json.loads returns items prefixing with 'u'
...on't be thrown by the printed output.
For example, try this:
print mail_accounts[0]["i"]
You won't see a u.
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Installing Google Protocol Buffers on mac
.... However homebrew has removed protobuf241 from its formula. I install it according @kksensei's answer manually and have to fix some error during the process.
During the make process, I get 3 error like following:
google/protobuf/message.cc:130:60: error: implicit instantiation of undefined t...
C++ Dynamic Shared Library on Linux
...e */
virtual void DoSomething();
private:
int x;
};
#endif
myclass.cc
#include "myclass.h"
#include <iostream>
using namespace std;
extern "C" MyClass* create_object()
{
return new MyClass;
}
extern "C" void destroy_object( MyClass* object )
{
delete object;
}
MyClass::MyClass...
Passing additional variables from command line to make
...assignments like this:
# Don't do this!
target:
$(MAKE) -C target CC=$(CC) CFLAGS=$(CFLAGS)
Instead, better solution might be to export these variables. Exporting a variable makes it into the environment of every shell invocation, and Make calls from these commands pick these environment...
How do I explicitly specify a Model's table-name mapping in Rails?
... a Model class called Countries and I want it to map to a DB table called 'cc'.
2 Answers
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