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Why do I get TypeError: can't multiply sequence by non-int of type 'float'?
...hat everyone here talked about multiplying a float with a string (but here all my element were floats all along) so the problem was actually using the * operator on a list.
For example:
import math
import numpy as np
alpha = 0.2
beta=1-alpha
C = (-math.log(1-beta))/alpha
coff = [0.0,0.01,0.0,0.3...
Eclipse comment/uncomment shortcut?
...
Use
Ctrl + SHIFT + L which will open a list of all major shortcuts for eclipse.
For single line java code comment and uncomment : Ctrl + / (Forward
Slash)
For multiple line java code comment : Ctrl + Shift +
/ (Forward Slash) and
Multiline uncomment : Ctrl + Shift +
\ ...
Multiplication on command line terminal
...ered Jun 14 '12 at 19:29
We Are All MonicaWe Are All Monica
11.3k77 gold badges3939 silver badges6767 bronze badges
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Difference between Java SE/EE/ME?
Which one should I install when I want to start learning Java? I'm going to start with some basics, so I will write simple programs that create files, directories, edit XML files and so on, nothing too complex for now.
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App Inventor 2 扩展 · App Inventor 2 中文网
...em in private versions of App Inventor that are hosted and managed individually.
App Inventor Extensions let anyone create Extension Components. Extension components can be used in building projects, just like other components. The difference is that extension components can be distributed on th...
Check whether a string matches a regex in JS
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Use regex.test() if all you want is a boolean result:
console.log(/^([a-z0-9]{5,})$/.test('abc1')); // false
console.log(/^([a-z0-9]{5,})$/.test('abc12')); // true
console.log(/^([a-z0-9]{5,})$/.test('abc123')); // true
...and ...
Switch statement: must default be the last case?
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The C99 standard is not explicit about this, but taking all facts together, it is perfectly valid.
A case and default label are equivalent to a goto label. See 6.8.1 Labeled statements. Especially interesting is 6.8.1.4, which enables the already mentioned Duff's Device:
Any ...
Why is @autoreleasepool still needed with ARC?
...tic Reference Counting), we don't need to think about memory management at all with Objective-C objects. It is not permitted to create NSAutoreleasePool s anymore, however there is a new syntax:
...
Git rebase: conflicts keep blocking progress
I have a git branch (called v4), that was made from master just yesterday. There were a couple of changes to master, that I want to get into v4. So, in v4, I tried to do a rebase from master, and one file keeps screwing things up: a one-line text file, that contains the version number. This file ...
Finalize vs Dispose
...difference between Dispose and Finalize (btw the Finalize method is still called a destructor in the language specification), so I'll just add a little about the scenarios where the Finalize method comes in handy.
Some types encapsulate disposable resources in a manner where it is easy to use and d...