I want to print all permutations of 123 in python? 123 132 213 231 312 321  How to get all permutations as a seperate numbers?
How to generate all permutations of a list? How do you generate all the permutations of a list in Python, independently of the type of elements in that list?  For example:  permutations([]) []  permutations([1]) [1]  permutations([1, 2]) [1, 2] [2, 1]  permutations([1, 2, 3]) [1, 2, 3] [1, 3, 2] [2, 1, 3] [2, 3, 1] [3, 1, 2] [3, 2, 1]
When to throw an exception? How does a magnet work? How can I integrate $\ln \left( x+\sqrt{1+x^2} \right) $? How to print the full NumPy array, without truncation? What is the best way to return an error from a function when I'm already returning a value? How to parse data in JSON format? Bash is not finding a program even though it's on my path Can we have a perfect field of characteristic $p$ with a non-archimedean valuation? Map matching links and ideas? I'm using OpenStreetMap and its vectorial road network and I'd like to implement a map matcher algorithm.   Currently I'm able, for each GPS position, to retrieve the nearest road segment and calculate the projection of this position to that segment, like on this image (Red pin is the pure GPS position, in blue the mapped segment and in Green the mapped position):    However, due to the lack of accuracy of the GPS, sometimes the mapped position jumps from segment to another and can provide some inconsistent mapped position from time to time.  My current algorithm is very basic : from the pure GPS position, I get the nearest segment and decide that the mapped matched position is on this one. I know that this can be really improved.  I can imagine that taking the vehicle direction into account will improve the map matching but do you know any other approach that would enable me to improve my map matcher ?  I seek any link, and/or open source software? How do I set exposure with a manual flash? I recently got an old Canon AE-1 film camera back in working order. I'd like to use my modern 430EXII Speedlight flash with it, however since there is no TTL metering, I have no idea how much the flash will affect the exposure of my shot (note that I have confirmed that the AE-1 will trigger the flash). I'd rather not discover that my shots were either blown out or way to dark after going through several rolls of film.  Are there any basic rules-of-thumb or basic calculations for anticipating how much a burst from the 430EXII will affect the exposure of a subject at various distances? How to prevent US post code formats I have an issue with American and Canada postcodes in accounts and contacts. Some of the users are creating the salesforce records with postcodes like (MD 20904), when we sending post code from salesforce to SAP integration, SAP system is rejecting salesforce records as postcode is not in correct format.   My question is:   what are actual US and canada post code formats? If Users are creating the post codes with MD 20904, how would prevent through validation rule like only accept sepecific format? Why does shrinkage work? In order to solve problems of model selection, a number of methods (LASSO, ridge regression, etc.) will shrink the coefficients of predictor variables towards zero. I am looking for an intuitive explanation of why this improves predictive ability. If the true effect of the variable was actually very large, why doesn't shrinking the parameter result in a worse prediction? Specific system of differential equations I have the following system of equations:  \begin{eqnarray}\frac{dx}{dt} = x(1 - x^2 - y^2) \\ \frac{dy}{dt} = y(4 - x^2 - y^2) \end{eqnarray}  I want to prove that if a solutions starts (at time $t = 0$) in the region   $$ G = \{(x, y) \in \mathbb{R}^2 : x &gt; 0, y &gt; 0 \text{ and } 1 &lt; x^2 + y^2  &lt; 4\} $$  that it remains there for all $t \geq 0$. I have already proven that, from $G$, a solution cannot cross the $x$-axis where $0 &lt; x &lt; 2$ or the $y$-axis where $0 &lt; y &lt; 2$ (since those line segments are orbits), but the pieces of the circles with radius 1 and 2 (where $x &gt; 0, y &gt; 0$) are the lines I haven't done yet. In this question we can focus on just the circle with radius 1 since the proof for the other circle is completely analogous to it.  In my book, there is a similar problem where they show that if a solution crosses a certain line, that solution attains its maximum or minimum value for $x$ and $y$, and then they derive a contradiction. However, in this case, for $n \geq 1$ the $n$-th derivative of $x$ equals 0 on the circle with radius 1. (If the second derivative were negative, $x$ would attain its maximum on the circle, a contradiction since $\frac{dx}{dt} &lt; 0$ in $G$, so $x$ is decreasing.)  I don't see why a solution can't cross the circle at all. On the circle, $\frac{dx}{dt} = 0$ and $\frac{dy}{dt} &gt; 0$, so after crossing the circle, the solution would go back up to $G$.  Is the circle itself an orbit?  EDIT I think I have found the answer. Using polar coordinates, I found $$ \frac{dr}{dt} = r - r^3 + 3r \sin^2(\theta) $$ Now, $$ \frac{dr}{dt} &gt; 0 \Leftrightarrow 0 &lt; r - r^3 + 3r \sin^2(\theta) \leq r - r^3 + 3r = 4r - r^3 $$ since $0 \leq \sin^2(\theta) \leq 1$. Note that $0 &lt; r \leq 1$ satisfies $4r - r^3 &gt; 0$, and thus $\frac{dr}{dt} &gt; 0$. Therefore, if a solution goes from $G$ to the edge of the unit circle, $r$ must, on the edge, either be decreasing or constant (i.e., its derivative is less than or equal to 0), contradicting the fact that the derivative is positive.  Can someone tell me if this is correct? Declare global variables in Visual Studio 2010 and VB.NET Do the Imperials know they are evil? I am trying to setup a trace flag to debug. When I select User in the dropdown and try to find System in there. It doesn't show up. What can I do ? Benevolent aliens who (initially) refuse to show themselves This is a sci-fi book where aliens arrive on Earth and push Earth towards world peace, but refuse to reveal themselves physically. When the aliens finally do show themselves, we find that they       look like .   I recall that the aliens seemed benevolent, but that humanity did not like the direction they were being told to go. I cannot remember the ending or if the aliens turned out to be truly benevolent. Nvidia graphics card no longer works in Windows 10 (error: Code 43) but works in Ubuntu Currently, when I boot into Windows, one monitor stays black (undetected), and the other can only display 800x600 resolution.  When I look at Device Manager &gt; Display Adapters &gt; NVIDIA GeForce GTX 970 &gt; General &gt; Device Status, it says "Windows has stopped this device because it has reported problems. (Code 43)".  Details &gt; Problem Code says "00002b". Details &gt; Status says:  01802400 DN_HAS_PROBLEM DN_DISABLEABLE DN_NT_ENUMERATOR DN_NT_DRIVER   When I then click into the Events tab, it says "Device PCI\VEN_10DE&amp;DEV_13C2&amp;SUBSYS_29763842&amp;REV_A1\4&amp;25438c51&amp;0&amp;0008 requires further installation."  I have a EVGA Nvidia GeForce GTX 970 graphics card with the latest drivers (376.19 from 12/1/2016).  My Windows 10 Pro has the latest updates and is at Version 1607, OS Build 14393.576.  My ASRock Z170 Pro4 motherboard BIOS is also updated to the latest version (7.00 from 10/4/2016).  I have dual Acer monitors with 1920x1080 resolution.  I downloaded Ubuntu 16.04.1 LTS onto a bootable USB drive and booted into the Ubuntu operating system instead of Windows. Both monitors immediately worked at full 1920x1080 resolution. So the hardware seems functional! My remaining challenge is to figure out why my video card has stopped working within Windows.  What I Have Tried   I've tried using Display Driver Uninstaller from Guru3d in Safe Mode to delete all drivers and try to install fresh.   I've tried many different versions of the driver dating back more than 12 months. I've tried reseating the card. I've tried moving the card to a different slot. EVGA's phone support told me to reinstall windows (Windows &gt; Reset this PC &gt; Keep my files). Unfortunately, I followed their advice (and now don't have any of my programs), and I still get Code 43 with the EVGA Nvidia card.   What I Have NOT Tried   I would love to try installing this card onto a different Windows 10 computer to see what happens, but I don't have access to any other computers. If you live northeast of Atlanta, let me know. ;-)   I'd appreciate any other ideas you have!. Delayed eraser experiment (Kim experiment) Will I receive an interference pattern on D0 detector   if D1, D2, D3, D4 exist in the set up of the experiment, but they are thousands of light years far? Simply, to set up the experiment so that I detect all of the signal photons on D0 before I detect any of idler photons! Prove that for all $n&gt;2$ there exists at least one prime $p$ such that $\sqrt{n}&lt;p&lt;n$ using elementary methods.  My try: If not, $\sum_{p&lt;\sqrt{n}} (\lfloor n/p \rfloor-\lfloor \sqrt{n}/p \rfloor) \geq n-\sqrt{n}$  then...?