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Checking if a string can be converted to float in Python
...False
print(isfloat("12.34.56")) False Two dots not allowed.
print(isfloat("#56")) False
print(isfloat("56%")) False
print(isfloat("0E0")) True
print(isfloat("x86E0")) False
print(isfloat("86-5")) ...
How do I check which version of NumPy I'm using?
...c Rodger: yeah, but your is more general to any module that cares to set a __version__.
– Esteban Küber
Oct 5 '09 at 14:13
57
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Getting the first character of a string with $str[0]
...am just not sure whether this is 'good practice', as that notation is generally used with arrays. This feature doesn't seem to be very well documented so I'm turning to you guys to tell me if it's all right – in all respects – to use this notation?
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How do I get the result of a command in a variable in windows?
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If you have to capture all the command output you can use a batch like this:
@ECHO OFF
IF NOT "%1"=="" GOTO ADDV
SET VAR=
FOR /F %%I IN ('DIR *.TXT /B /O:D') DO CALL %0 %%I
SET VAR
GOTO END
:ADDV
SET VAR=%VAR%!%1
:END
All output lines are stor...
How to delete (not cut) in Vim?
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Use the "black hole register", "_ to really delete something: "_d.
Use "_dP to paste something and keep it available for further pasting.
For the second question, you could use <C-o>dw. <C-o> is used to execute a normal command without leaving ...
How can I join elements of an array in Bash?
... +1. What about printf -v bar ",%s" "${foo[@]}". It is one fork less (actually clone). It is even forking reading a file: printf -v bar ",%s" $(<infile).
– TrueY
Jun 8 '13 at 22:55
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What are “connecting characters” in Java identifiers?
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I'm not sure that actually fully answers the (implied) question of which characters may start a Java identifier. Following links we end up at Character.isJavaIdentifierStart() which states A character may start a Java identifier if and only if one...
Difference between fold and reduce?
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So basically instead of doing fold, you can simply add that initial value to the start of the list and do reduce? What's the point of fold then?
– Pacerier
Feb 7 '17 at 9:42
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_=> what does this underscore mean in Lambda expressions?
What does an lambda expression like _=> expr mean?
5 Answers
5
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How do I install cygwin components from the command line?
... the Cygwin package similar to apt-get on Debian or yum on redhat that allows me to install components from the command line?
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