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not None test in Python [duplicate]
...r of the latter two, since val could potentially be of a type that defines __eq__() to return true when passed None.
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MFC Grid control 2.27 - C/C++ - 清泛网移动版 - 专注C/C++及内核技术
...ch and useable as something of this form can be. Dozens of developers from all over the world have contributed fixes, improvements and suggestions over the 4 years that the grid has been growing, and there is still no end in sight. Most of the fixes have been sent in by readers so I'm trusting that ...
“No such file or directory” error when executing a binary
I was installing a binary Linux application on Ubuntu 9.10 x86_64. The app shipped with an old version of gzip (1.2.4), that was compiled for a much older kernel:
...
Programmatically change UITextField Keyboard type
...
_textField .keyboardType = UIKeyboardTypeAlphabet;
_textField .keyboardType = UIKeyboardTypeASCIICapable;
_textField .keyboardType = UIKeyboardTypeDecimalPad;
_textField .keyboardType = UIKeyboardTypeDefault;
_textField .keyb...
How to get Scala List from Java List?
...now built into the language using:
import scala.collection.JavaConversions._
...
lst.toList.foreach{ node => .... }
works. asScala did not work
In 2.12.x use import scala.collection.JavaConverters._
In 2.13.x use import scala.jdk.CollectionConverters._
...
Find out how much memory is being used by an object in Python [duplicate]
...and internal structures related to object types and garbage collection. Finally, some python objects have non-obvious behaviors. For instance, lists reserve space for more objects than they have, most of the time; dicts are even more complicated since they can operate in different ways (they have a ...
How to get RelativeLayout working with merge and include?
...
This is really easier, less hardcoded, and more optimized solution than packing <include/> into another layout. Think what would you do if you would work with lists.
– teoREtik
Feb 2 '12 at ...
pandas GroupBy columns with NaN (missing) values
...n the Missing Data section of the docs:
NA groups in GroupBy are automatically excluded. This behavior is consistent with R, for example.
One workaround is to use a placeholder before doing the groupby (e.g. -1):
In [11]: df.fillna(-1)
Out[11]:
a b
0 1 4
1 2 -1
2 3 6
In [12]: df.fil...
how to return index of a sorted list? [duplicate]
...ray([2,3,1,4,5])
>>> vals
array([2, 3, 1, 4, 5])
>>> sort_index = numpy.argsort(vals)
>>> sort_index
array([2, 0, 1, 3, 4])
If not available, taken from this question, this is the fastest method:
>>> vals = [2,3,1,4,5]
>>> sorted(range(len(vals)), key=...
Import multiple csv files into pandas and concatenate into one DataFrame
...
If you have same columns in all your csv files then you can try the code below.
I have added header=0 so that after reading csv first row can be assigned as the column names.
import pandas as pd
import glob
path = r'C:\DRO\DCL_rawdata_files' # use you...