How can I improve the sharpness of my Sigma 50mm 1.4 DG HSM lens? I've had it for a while but haven't used it much because it is not sharp. Suggestions? Can it be sent off and is that expensive?
Why are my photos not crisp? I use a Canon EOS Rebel T3i (600D) with the kit lens. I have experimented a lot with different settings and modes, but I feel like I have wasted many good shots that could have looked amazing, if only they were a little bit sharper.  I use auto-focus on most of my pictures and make sure to choose the right focus point, but all of my photos are still a little bit out of focus. When I zoom in, I can see that the pixels are not very crisp or well-aligned.  I am not sure if this issue is caused by my equipment or skills.
How are you dealing with the  in your machine learning models? Let's say you used to predict the number of sales each month. The virus affected your results last year and it will affect for at least a couple of months. So your model, I guess, is missing a lot. What are some approaches we can use to fix our models? Symbolizing layer with graduated colors by date/time field? I've got a layer of polygons where each has a date associated with it.  I want to color the polygons with graduated colors, but I want the colors to start with the newest polygons and fade to the oldest polygons.  So far I haven't been able to find a way to do this in ArcMap (&lt;= 9.3.1) other than to create a new field and calculate some integer or float value based on the date.  Is it possible to use a date or time field directly?   The data is natively a date-time value There are far too many records to use any unique-value renderer Converting the date to a numerical field is an answer for a different question. WOL was working great on Bionic until yesterday's kernel update. How to diagnose/recover it?  Edit: if set to boot from 4.15.0-23 kernel it works. If set to boot from 4.15.0-24 it does not.  Edit2: WoL can be enabled with   sudo ethtool -s [card] wol g   but it isn't persistent. Searching for how to set it every boot.  Edit3: Per a comment by Kai-Heng Feng on this  this was an advertent change! (and therefore not a bug)  This is because the fix of LP: #1752772 has one commit [1] that disables WoL by default. Set WoL explicitly should solve your issue.  [1] https://github.com/torvalds/linux/commit/7edf6d314cd061e1d0a1b7bc0b511d64322c3f72 On the hardness of data to learn Almost in all texts which are discussing theorems of statistical learning, they assume analyzing arbitrary unknown distribution (the worst case). But in practice different problems (different data) have different levels of hardness, for example linear separable data is easier to learn than the data that are less (or not) separable by hyperplanes.  Are there any works on formalizing the hardness of data (similar to the stuff done in complexity theory)  Note: I am not sure if the same as analyzing VC-dimension or not, but I think it is not. The recipe that I used did not call for cornstarch or corn syrup. The result is that they are slightly wet. Can I do anything to dry them up, such as dusting them with corn flour?  I did dredge them in a mixture of confectioners sugar and corn flour; it helped a little, but I think I will find a recipe that has corn starch in it for next time! How can I check which DNS server am I using (in Linux)? I am using network manager and a wired connection to my university's LAN. (I am trying to find out why my domain doesn't get resolved) Windows vs Linux Local Time? Ever since I started using Linux in dualboot with Windows I noticed that when I rebooted the machine, the time on the other OS was wrong, e.g. it was 12:00 on Linux, then I rebooted and on Windows it was 18:00, and when I checked the BIOS, the RTC was set to 18:00. Since my timezone is -06:00 CST I assume Linux just sets the RTC’s time to UTC and re-calculates the time based on the timezone, whereas Windows just sets the RTC to the local time. Both use the same NTP server to sync the time.  The question is, which one is doing the right thing? On which one should I set the timezone setting to UTC in order to have the right time on both? I am able to locate files in a folder containing a specific text string using this command:  grep -lir 'string' ~/directory/*   How do I move the files that appear in the above result to another location? How do I remove an element from a list by index in Python?  I found the list.remove method, but say I want to remove the last element, how do I do this? It seems like the default remove searches the list, but I don't want any search to be performed. Find out trace of a given matrix $A$ with entries from $\mathbb{Z}_{227}$ Let $A$ be a $227\times 227$ matrix with entries in $\mathbb{Z}_{227}$ such that all of its eigen values are distinct. What would be its trace? I think it is zero by adding all 227 elements but i am not sure.  Edited: Here I have assumed that eigenvalues are in a base field. Integral equation problem How can I share an iCloud photo album? So this is what I'm trying to do in Drupal 6:  Node type A is video, node type B is a person Nodetype A has a reference field where you can enter a reference to any Node from nodetype B  how can I create a block view which will be displayed on nodes from node type b, which will show all the nodes from node type A where the current node from node type B is referenced? Why do we use the simple past but not the present or future in the following expressions:  Don't you think it's time we went a little further Don't you think it's time we ate Don't you think it's time we went home Covering ten dots on a table with ten equal-sized coins: explanation of proof Note: . I have moved it here because:   I am curious about the answer The OP has not shown any interest in moving it himself     In the Communications of the ACM, , Peter Winkler asked the following question:     On the table before us are 10 dots,   and in our pocket are 10 $1 coins.   Prove the coins can be placed on the   table (no two overlapping) in such a   way that all dots are covered. Figure   2 shows a valid placement of the coins   for this particular set of dots; they   are transparent so we can see them.   The three coins at the bottom are not   needed.   In the , he presented his proof:     We had to show that any 10 dots on a   table can be covered by   non-overlapping &#36;1 coins, in a problem   devised by Naoki Inaba and sent to me   by his friend, Hirokazu Iwasawa, both   puzzle mavens in Japan.      The key is to note that packing disks   arranged in a honeycomb pattern cover   more than 90% of the plane. But how do   we know they do? A disk of radius one   fits inside a regular hexagon made up   of six equilateral triangles of   altitude one. Since each such triangle   has area $\frac{\sqrt{3}}{3}$, the hexagon   itself has area $2 \sqrt{3}$; since the   hexagons tile the plane in a honeycomb   pattern, the disks, each with area $\pi$,   cover $\frac{\pi}{2\sqrt{3}}\approx .9069$ of the   plane's surface.      It follows that if the disks are   placed randomly on the plane, the   probability that any particular point   is covered is .9069. Therefore, if we   randomly place lots of &#36;1 coins   (borrowed) on the table in a hexagonal   pattern, on average, 9.069 of our 10   points will be covered, meaning at   least some of the time all 10 will be   covered. (We need at most only 10   coins so give back the rest.)      What does it mean that the disks cover   90.69% of the infinite plane? The easiest way to answer is to say,   perhaps, that the percentage of any   large square covered by the disks   approaches this value as the square   expands. What is "random" about the   placement of the disks? One way to   think it through is to fix any packing   and any disk within it, then pick a   point uniformly at random from the   honeycomb hexagon containing the disk   and move the disk so its center is at   the chosen point.   I don't understand. Doesn't the probabilistic nature of this proof simply mean that in the majority of configurations, all 10 dots can be covered. Can't we still come up with a configuration involving 10 (or less) dots where one of the dots can't be covered? Trying to dual boot Ubuntu 14.10 with Windows 10, last one not detected I have a laptop, and I'm going to install Ubuntu (I have experience, and I have  successfully installed , Ubuntu, , , , , , etc.), but installing  (Utopic Unicorn) alongside , Ubuntu can't detect Windows.  It shows me like there's no OS, but I have Windows&nbsp;10.  I have two primary partitions by the way if I manually install. If the Ubuntu installer can't detect Windows&nbsp;10, will it be detected at ? My adoptable storage is full. How can I move the data to a bigger MicroSD card? I've got a Moto G 2014 LTE running CM13. When I found out about the whole 'adopt SD card as internal storage' thing, I was quite excited, as the actual internal storage on this phone is tiny. I set up a 16gb micro SD, the biggest I had at the time, and have been using it with minimal problems.  Fast-forward to this day, and I now have a 64gb micro SD that I want to use instead of the 16gb one. However, I'm at a loss as to the best way to copy the data over onto the new one, or if it's even possible. The ideas I've got so far include:   Titanium Backup all [system] apps, factory reset, format new SD and then restore (should work, but a massive pain) NANDroid the SD card onto a USB OTG stick, then restore to the new one (pretty sure this is a bad idea and won't work, but...) Copy all the stuff onto my computer via my phone through a file manager of some sort (I have a linux/linux/windows triple boot, so file format isn't a problem), format the new SD into phone, and copy back (can't be that simple, can it? Hidden/inaccessible files?) Copy the files onto USB OTG with a root file explorer app, reformat the SD as portable, format the new one as adopted, and then copy them back (could work, except for the point below)  with the command adb shell sm set-force-adoptable true, use a root browser to copy all the data over from the old SD, format the old SD as external and remove it, and take the new SD and put it in the SD card slot (seems overly complicated, and also suffers the below pitfall)   The other thing that worries me is mount points: will the apps with externally-stored data know to look at the new SD card for it? Will I have to remount it in a specific location with the shell each boot (or use an init.d script perhaps)? I suppose that it can always be accessed through /sdcard or /storage/emulated/0, but I'm not 100% sure what goes on behind the scenes.  I've got recent NANDroid backups, so if anyone can eliminate the options that definitely won't work (or say which one[s] probably will), I can try them and report back in case someone stumbles across this question in the future.  EDIT: So, my phone further bit the dust and got to the point where it got into a pretty major bootloop. Ended up having to flash a whole new ROM. As such, I probably won't be able to test the full image/decryption/etc. method that I was originally planning. However, I will write up what I've discovered so far in case anyone wants to take up this particular method in the future:   Image the old SD with dd as follows: sudo dd if=/dev/mmcblk0 of=~/SDCardBackup.img, where /dev/mmcblk0 is the location of the sd card as obtainable through lsblk Restore the image you just made to the NEW sd card : sudo dd bs=4M if=~/SDCardBackup.img of=/dev/mmcblk0 (you may have to unmount it first) From here on in, I was following  (thanks @beeshyams!) tutorial, which explains the next steps way better than I ever could have done. The plan was to decrypt the storage and resize the main partition with gparted. I had no idea whether it would work or not, but I felt it was worth a try. However, when I came to run the actual decryption command using the key I'd extracted, I got an error (which I believe was my shoddy linux skills more than anything).   As I say, I have no idea if the above method would work or not even if everything did go to plan. Also, feel free to correct any of my commands above if I mis-typed them (I'm on Windows currently, so this is all from memory.) If this info helps anyone, then good. But until then,  should work fine.  Thanks, Jackdafish Align equation left USB flash drive not working or is appearing as an empty disk drive, Disk Management reports "No Media" with 0 bytes size I have a USB flash drive which is no longer recognized by my computer. Windows Disk Management and DiskPart report No Media with no storage space (0 bytes) on the drive and I cannot partition or format the drive:     If the drive appears in Windows Explorer, trying to access it returns an error message indicating that there is no disk inserted, such as the following:     Please insert a disk into drive X:.   Various disk partitioning and data recovery utilities don't recognize the drive or only give a generic name for the drive and cannot access the contents of the drive.  What can I do? How do I recover data from the drive?     This question comes up often and the answers are usually the same. This post is meant to provide a definitive, canonical answer for this problem. Feel free to edit the answer to add additional details. Just a few questions about Hyper-V virtual machines and clustering I have been using Microsoft’s Hyper-V technology for a little while now, but I am just now dipping my toe into clustering.  In particular, I am trying to implement a fault-tolerant SQL DB. This involves setting up two VMs, clustering them via Failover Cluster, and then installing SQL Server in some fashion. I have two physical machines - one high-end and rather beefy “heavy lifter” to contain the majority of the VMs, and another “backup” (a repurposed desktop) to hold the essential “secondary” (or failover) AD-DC, SQL and FS VMs.  The main reason why I find the failover cluster at the VM level so attractive is that it presents a single IP and DNS entry to the network as a whole - if one machine (physical or virtual) goes down, you might loose some ping and the connections get reset, but the network applications (Microsoft RMS connection to backend SQL) can still connect to a viable DB without having to mess around with the settings at all.  My first question is in terms of SQL Server itself. If I have a cluster between two VMs, does it make more sense to install the SQL Server in Failover Cluster configuration or should I simply install it in a stand-alone config and mirror the DBs? For example,  suggests just mirroring the DBs, but do I just mirror standalone DBs on standalone VMs, or can I get the network and failover benefits of clustered VMs while still utilizing (on each clustered VM) standalone DBs that have been mirrored between each other?  As well, I have come across a lot of documentation about SQL clustering, but most assume a number (#>2) of physical machines to hold not only the actual SQL VMs but also the Quorum and Witness stores. I will not be able to muster more than two physical machines. As such, I will have to be satisfied with a VM cluster that does not exceed two VMs (one for each physical machine).  Another issue involves MSDTC - the Distributed Transaction Coordinator. When attempting to install the SQL Failover Cluster (I never completed it for this reason) it threw a hissy fit because MSDTC had not been clustered. Search as I might, I have not yet found a way to do so under Windows Server 2012 R2. I have found , but these instructions don’t align with 2012 R2 (at least, not in a way that allows me to successfully cluster MSDTC). Plus,  that I have found for SQL Server Failover Cluster installation suggest that a third “network device” - shared network storage (a SAN) - is required for the DB itself (and other functionality). I do not have this, and won’t be getting this. Most of my storage exists on the “heavy lifter” that was designed for all of the “primary” VMs. If that physical machine goes down, so does the storage. The secondary server does have enough resources for an AD-DC Server, an SQL server and a File Server, so it will handle the “secondary” failover versions of those VMs (clustered or not).  My final question involves file servers. If I cluster file servers between two VMs (one on my “heavy lifter” and another on my “backup”, how do I mirror the data between them? Clustering VMs only provides a single point of access on the network for a resource, it doesn’t exactly replicate data between the two - that is left to the services that serve up that data. I am unsure how I can ensure that file server data between two clustered file server VMs can be properly mirrored. Remember, I only have two devices to be used here - my primary machine and a backup secondary. There is no chance of me obtaining a SAN or any other type of network attached storage. What exists on the machines must act as the storage.  Thanks in advance for any suggestions.