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Assignment inside lambda expression in Python
...ctic reasons. For example, we will be able to write the following:
import sys
say_hello = lambda: (
message := "Hello world",
sys.stdout.write(message + "\n")
)[-1]
say_hello()
In Python 2, it was possible to perform local assignments as a side effect of list comprehensions.
import sys
s...
“TypeError: (Integer) is not JSON serializable” when serializing JSON in Python?
... provided by Serhiy Storchaka. It works very well so I paste it here:
def convert(o):
if isinstance(o, numpy.int64): return int(o)
raise TypeError
json.dumps({'value': numpy.int64(42)}, default=convert)
share
...
How to convert strings into integers in Python?
...
int() is the Python standard built-in function to convert a string into an integer value. You call it with a string containing a number as the argument, and it returns the number converted to an integer:
print (int("1") + 1)
The above prints 2.
If you know the structure ...
When should I use cross apply over inner join?
...ross apply. It might have other uses but I think this is the reason it was introduced. Without it table functions would not be usable in a lot of situations. technet.microsoft.com/en-us/library/ms175156.aspx
– MikeKulls
Aug 12 '11 at 0:38
...
Converting Integer to Long
...
No, you can't cast Integer to Long, even though you can convert from int to long. For an individual value which is known to be a number and you want to get the long value, you could use:
Number tmp = getValueByReflection(inv.var1(), classUnderTest, runtimeInstance);
Long value1 =...
pythonw.exe or python.exe?
...ng console window, python.exe opens a new console window.
Standard streams sys.stdin, sys.stdout and sys.stderr are connected to the console window.
Execution is synchronous when launched from a cmd.exe or PowerShell console window: See eryksun's 1st comment below.
If a new console window was crea...
Way to read first few lines for pandas dataframe
...
I think you can use the nrows parameter. From the docs:
nrows : int, default None
Number of rows of file to read. Useful for reading pieces of large files
which seems to work. Using one of the standard large test files (988504479 bytes, 5344499 lines):
In [1]: import pandas as pd...
How to get current timestamp in milliseconds since 1970 just the way Java gets
...e <sys/time.h>
struct timeval tp;
gettimeofday(&tp, NULL);
long int ms = tp.tv_sec * 1000 + tp.tv_usec / 1000;
refer this.
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How to add to the PYTHONPATH in Windows, so it finds my modules/packages?
... for me really well on windows.
My Computer > Properties > Advanced System Settings > Environment Variables >
Just add the path as C:\Python27 (or wherever you installed python)
OR
Then under system variables I create a new Variable called PythonPath. In this variable I have C:\Pyth...
Convert List into Comma-Separated String
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In .NET 3.5 and below you have to explicitly convert your list to array with lst.ToArray(), as there is no direct overload there yet.
– Anton
Dec 15 '13 at 11:09
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