I just downloaded ubuntu from the website &amp; had it saved under my documents but i can't seem to figure out how to get to the next phase of it being installed &amp; running on my laptop. Most all the instructions I've come across don't seem to mention anything other than when I reboot I should be given the option to choose to run it or windows...not sure if this is before or after the installer should be done or how it is to be done. A little help &amp; guidance will be appreciated, thank you.
I would like to see a full how-to guide on how to install Ubuntu.
Batch Convert Images from One Format to Another while maintaining directory structure, and removing originals I've looked at , and while it works there a few issues:   All converted images are placed in the directory from which the command is called. The original images are kept.   I need to convert around 70,000 .tif and .jpgs to .pngs.  It's really important the the files when converted are placed in their normal directories.    I can do a batch rm of .tff/.jpg's at the end if that's the best way to handle removing the old files. ArcPy importing error after setting path? This questions has been asked before too and I did go through most of the suggestions. Things I have tried so far: setting up correct  path variable environment, installing anaconda 32 bits, python 2.7, or even switching to python 2.7 in cmd while initially using Anaconda 3 , adding Desktop 10.4.pth file with  following path.  C:\Program Files (x86)\ArcGIS\Desktop10.4\bin C:\Program Files (x86)\ArcGIS\Desktop10.4\ArcPy C:\Program Files (x86)\ArcGIS\Desktop10.4\ArcToolBox\Scripts   I also added those paths in environment variable   These suggestions help me to reduce the error. But Now I am getting a different error. Looks like python can find arcpy but missing another package.  Getting this error while trying to import arcpy in python 3.6.   File "C:\Program Files (x86)\ArcGIS\Desktop10.4\ArcPy\arcpy\__init__.py", line 22, in &lt;module&gt;     from arcpy.geoprocessing import gp    File "C:\Program Files (x86)\ArcGIS\Desktop10.4\ArcPy\arcpy\geoprocessing\__init__.py", line 14, in &lt;module&gt;     from _base import *  ModuleNotFoundError: No module named '_base'   Any suggestions? `du -b` shows different size than `ls` Map of with object references as keys? Let $G$ be a group of order $150$.  I must show that it has a normal subgroup of order $25$.  The hint says to show that is has a normal subgroup of order $5$ or $25$.  Now from Sylow, I know that the number $n_5$ of Sylow-$5$ subgroups (which each have $25$ elements) must be either $1$ or $6$, since $n_5$ must also divide $6$.  Now clearly if $n_5=1$ we are done, so I can assume that $n_5=6$.  My problem is I haven't figured out how to use this information (I am going for a contradiction, just based on what the problem asks me to prove).  I know by Cauchy's theorem I can get a subgroup of order $5$, but I don't see immediately if it must be normal.   Any direction I should try to be moving? Anyone know of a custom GPS ROM for Samsung Galaxy 5? Possible Duplicate:          I recently bought a Samsung Galaxy 5 (model number GT-I5500) and I'm new to the android world.   I'm not satisfied with the performance of the GPS on my cell phone so I thought it would be interesting to use a custom ROM to see if it improves a bit.   Anyone knows of a ROM that was tested in this model? Is there a single word for "moving unhinderedly"? What do I do when I walk into a room with a broken item and both children shrug their shoulders and say "Wasn't me"? I'm trying to get my kids to be honest and take responsibility.   I'm seeing a repeated pattern where one or both of my kids will lie to get out of trouble. They're starting to see that they can deny responsiblity.   Our current system of reward involves a marble jar, where the family will go out for a collective treat. When this stuff happens we take marbles out of the jar as a joint penalty.   This seems to be decreasing in effectiveness.   My question is: What do I do when I walk into a room with a broken item and both children shrug their shoulders and say "Wasn't me"?  Clarification: Kids are girl: 5 and boy: 4. Cultural context is Australian middle class with two university educated parents. Manually calculated $R^2$ doesn't match up with randomForest() $R^2$ for testing new data I know this is a fairly specific R question, but I may be thinking about proportion variance explained, $R^2$, incorrectly. Here goes.  I'm trying to use the R package randomForest. I have some training data and testing data. When I fit a random forest model, the randomForest function allows you to input new testing data to test. It then tells you the percentage of variance explained in this new data. When I look at this, I get one number.  When I use the predict() function to predict the outcome value of the testing data based on the model fit from the training data, and I take the squared correlation coefficient between these values and the actual outcome values for the testing data, I get a different number. These values don't match up.   Here's some R code to demonstrate the problem.  # use the built in iris data data(iris)  #load the randomForest library library(randomForest)  # split the data into training and testing sets index &lt;- 1:nrow(iris) trainindex &lt;- sample(index, trunc(length(index)/2)) trainset &lt;- iris[trainindex, ] testset &lt;- iris[-trainindex, ]  # fit a model to the training set (column 1, Sepal.Length, will be the outcome) set.seed(42) model &lt;- randomForest(x=trainset[ ,-1],y=trainset[ ,1])  # predict values for the testing set (the first column is the outcome, leave it out) predicted &lt;- predict(model, testset[ ,-1])  # what's the squared correlation coefficient between predicted and actual values? cor(predicted, testset[, 1])^2  # now, refit the model using built-in x.test and y.test set.seed(42) randomForest(x=trainset[ ,-1], y=trainset[ ,1], xtest=testset[ ,-1], ytest=testset[ ,1]) What original Dr Who episodes are left when not watching unfinished stories? On a whim the other day, I changed my meta name from Lord Torgamus to Popular Demand.  I just noticed that the old name has "stuck" to the author tag of ; everywhere else on meta, my new name displays as expected.  Is this a feature?  Is it a bug?  Mostly I'm just curious, as I can't think of a strong reason in favor of keeping this behavior or a strong reason for changing it.  A question somewhat like this has been raised before as , but the previous poster implied that the issue had something to do with migration, which my situation shows is not the case. A riddle about guessing hat colours (which is not among the commonly known ones) This is a riddle I heard recently, and my question is if someone happens to know the solution. I'm asking this out of curiosity more than anything else.  So here it is. The riddle is one of the countless variations of the "prisoners have to guess their hat colour" puzzle. $n$ prisoners are put a hat on top of their head, which can be red or blue. The colours are chosen at random by $n$ independent fair coin tosses. Then each prisoner can guess their own hat colour (red or blue) or pass. The prisoners can see each other, but not hear each other's calls and of course they have no other means of communication. This means that each call can only depend on the other prisoners' hat colours. However, before the distributing of hats begins, the prisoners are told the rules and can agree on a strategy. The prisoners win iff no prisoner guesses wrong and at least one prisoner guesses right. Which strategy should the prisoners use so that the winning probability becomes maximal?  Some remarks:   A simple strategy is that one player just guesses and all other players pass, so that the maximal probabilty is at least 1/2. For $n=2$ this strategy is optimal. For $n=3$, there is a strategy that wins in 6 out of 8 cases: When a player sees (red,red) he guesses blue, for (blue,blue) he guesses red, and otherwise he passes. More generally this shows that the maximal probability is at least 3/4 for $n\ge 3$. It's possible to show that any strategy fails for at least 2 hat colour configurations (unless $n=1$), which shows that the above strategy is optimal for $n=3$. For $n=4$ there are more than $10^{15}$ strategies, and for $n=5$ it's about $10^{38}$ strategies, making it quite infeasible to just use a brute-force computer program (maybe for $n=4$ it's possible when exploiting the obvious symmetries). When changing the rules slightly by forbidding players to pass, then the maximal winning probability is always 1/2. This is a nice little exercise.   Actually I heard the riddle only for $n=3$ and then thought about the general $n$. So it's entirely possible that there is no nice solution. How are second order nonlinear ordinary differential equations solved? Eigen Values Proof a.) Let A and B be $n$ x $n$ matrices. Prove that the matrix products   $AB$  and $BA$ have the same eigenvalues.      b.) Prove that every eigenvalue of a matrix A is also an eigenvalue of   its transpose $A^T$. Also, prove that if v is an eigenvector of A with   eigenvalue $\lambda$ and w is an eigenvector of $A^T$ with a different   eigenvalue $\mu \ne \lambda$, then v and w are orthogonal vectors with   respect to the dot product.   For a, I know that if their eigenvalues are the same then their eigenvectors must relate too.    For the first part of b, is it similar to proving that the $det(A) =det (A^T)$? And, I do not know how to do the second part. Shoenfield introductory mathematical logic book alternatives I was originally intending on reading Mathematical Logic by Joseph R. Shoenfield (1967) though after reading  I get the impression that despite being influential for the time it was written, there now exist many new books written from our current perspective that tend to be easier on non-experts by offering more thorough explanations for each new topic being introduced.   As of now I have a basic knowledge of abstract algebra (basics on vector spaces, rings, groups etc.) from doing elementary number theory and taking a course on linear algebra, also I have completed  a year long course on real analysis which used a lot of elementary set theory and some order theory.   With all that said, I was hoping based on my current basic knowledge of math that someone could recommend me an introductory book on mathematical logic which I could use as an alternative to Shoenfield's and which addresses Peter Smith's criticisms - any help would be greatly appreciated. Showing margins/frames in beamer slides The following  (links to pdf) in the  has no provided source. The book  by Ash and Gross seems to use a similar style. Where can I find hints for typesetting publication standard articles/books as above in TeX. I looked around a bit but couldnt find much from else from keyword searches.  Particularly, I am looking at the chapter headings, title page design, and the mirror effect. Sorry for the title, as I dont really know what its called. What is the plural form of "Software"? Height of an HTML select box (dropdown) postfix discard or change Message-ID header based on another header line I want to change the Message-ID header or better yet, discard it. I know everyone is going to ask "Why would you want to do that?" because I know it sounds weird to even write it.  Well I am developing a system that saves an incoming e-mail in EML format, changes it and sends it to the user, at some point the user can request to have the original EML sent to him/her. The issue is that when I re-send the EML it has the same Message-ID header which causes exchange servers to drop the re-send.  Of course I am hoping there is some option through postfix to do this, otherwise I will need to parse and change the EML but I rather not do that.  I tried to do this with "header_checks" and it works BUT I need to be able to do this conditionally, meaning only on a specific occasion, which I can identify by looking at the other headers, I want to remove the Message-ID.