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Replacing Pandas or Numpy Nan with a None to use with MysqlDB
...n use where, it's worth noting that you can do this natively in pandas:
df1 = df.where(pd.notnull(df), None)
Note: this changes the dtype of all columns to object.
Example:
In [1]: df = pd.DataFrame([1, np.nan])
In [2]: df
Out[2]:
0
0 1
1 NaN
In [3]: df1 = df.where(pd.notnull(df), None...
How do I compare two strings in Perl?
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186
See perldoc perlop. Use lt, gt, eq, ne, and cmp as appropriate for string comparisons:
Binary...
Regular expression search replace in Sublime Text 2
...
Usually a back-reference is either $1 or \1 (backslash one) for the first capture group (the first match of a pattern in parentheses), and indeed Sublime supports both syntaxes. So try:
my name used to be \1
or
my name used to be $1
Also note that your or...
Printf width specifier to maintain precision of floating-point value
... in:
#include <float.h>
int Digs = DECIMAL_DIG;
double OneSeventh = 1.0/7.0;
printf("%.*e\n", Digs, OneSeventh);
// 1.428571428571428492127e-01
But let's dig deeper ...
Mathematically, the answer is "0.142857 142857 142857 ...", but we are using finite precision floating point numbers.
L...
UnicodeDecodeError, invalid continuation byte
Why is the below item failing? Why does it succeed with "latin-1" codec?
10 Answers
10...
Eclipse RCP开发桌面程序 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...候，会先执行Application的run方法，run方法的代码如下：
1 public Object run(Object args) throws Exception {
2 Display display = PlatformUI.createDisplay();
3 try {
4 int returnCode = PlatformUI.createAndRunWorkbench(display, new Ap...
Test if a vector contains a given element
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521
Both the match() (returns the first appearance) and %in% (returns a Boolean) functions are desig...
How to compare two floating point numbers in Bash?
...
17 Answers
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