shell get parse arguments
Using getopts to process long and short command line options
Is it shell portable to run a command on the same line after variable assignment? Is there any standard that covers the portability of running a command after variable assignment on the same line?  APPLE="cider" echo hi   How portable is something like that? Where will it work and where won't it?   Also: my shell scripts start with #!/bin/sh if that makes any difference. Calculating Mean for Multiple Rows in ArcGIS for Desktop? I am trying to calculate a mean across a multiple number of attribute rows and have this value added to a new field that I have entered in the attribute table. I have an attribute table which has a number of different ecoregion types associated with them.  For example:  If I select "Arid Canyonlands" there are 3 attribute rows that are selected, each with their own "mean". I am trying to add a new field to the attribute table which will take the "mean" of these three and populate that value in the new field created. I could manually do it through an editing session and using a calculator but just wanted to know if there is an easier way to actually do it through field calculator? On , there are download options for only certain logos/icons. Shouldn't this include all the graduated sites logos/icons? I think it should. How to create a circular shaped grid, similar to a manhole cover Everytime I sudo apt-get update it always not complete and will say in the end  E: Read error - read (5: Input/output error) E: The package lists or status file could not be parsed or opened.   Same goes, when I try to install something and do sudo apt-get install &lt;some app&gt;  What should I do ? I admit, that my drive has bad sectors, could that be the reason? Is there anything else I can do? I need to prove that the center of $A_n$ is trivial for $n \geq 4$.  $Z(A_3) = A_3$, since $A_3 = \mathbb{Z}/3\mathbb{Z}$ is commutative.  One idea is two use "counting" technique. First of, all we count cojugacy classes of even permutations in $S_n$. It's the classes correspodning to the types $[\lambda_1, ..., \lambda_r]$ where $n \equiv r \mod 2$  Now, the conjugacy class in $S_n$ correspoding to the type $[\lambda_1, ..., \lambda_r]$ splits into two equal-sized classes in $A_n$ if $\lambda_1, ..., \lambda_r$ are distinct odd numbers. If they aren't then it is preserved in $A_n$.  Then we can use "the counting formula"(  ) of elements in each "even" class of $S_n$ and divide one by $2$ if needed.  Still, I'm not sure if it can be done. Seems to be a lot of work there. Maybe there are other, he easier ways? Or, maybe, it is the way, in this case, I wouild appreciate any advices. How to include custom non-system folder under This PC in Windows 8.1? I've recently upgraded from Windows 8 to 8.1 and noticed the restructured This PC folder, formerly Computer.   What I want to achieve is to include custom folder under "This PC".    What I've found after googling is that what is displayed under "This PC" is stored in registries under   HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\MyComputer\NameSpace  However those folders (such as Desktop, Documents, etc) are referenced via CLSID and the folder I want to include in the list does not have CLSID. I have installed Ubuntu 15.04 on my laptop with RTL8723BE Wi-fi card. But it is always disconnecting from network. I have tried echo "options rtl8723be fwlps=N ips=N" | sudo tee /etc/modprobe.d/rtl8723be.conf but that didn't helped. What can I do to prevent the wifi from disconnecting? If I upgrade to kernel 4.X, will it help?  ~$ lspci -knn | grep Net -A2  09:00.0 Network controller [0280]: Realtek Semiconductor Co., Ltd. RTL8723BE PCIe Wireless Network Adapter [10ec:b723]     Subsystem: Hewlett-Packard Company Device [103c:2231]     Kernel driver in use: rtl8723be   ~$ rfkill list 0: hci0: Bluetooth     Soft blocked: yes     Hard blocked: no 1: phy0: Wireless LAN     Soft blocked: no     Hard blocked: no   ~$ ifconfig &amp;&amp; iwconfig &amp;&amp; route -n &amp;&amp; ping -c 1 google.com eth0      Link encap:Ethernet  HWaddr 38:63:bb:cd:4a:7e             UP BROADCAST MULTICAST  MTU:1500  Metric:1           RX packets:3 errors:0 dropped:0 overruns:0 frame:0           TX packets:53 errors:0 dropped:0 overruns:0 carrier:0           collisions:0 txqueuelen:1000            RX bytes:752 (752.0 B)  TX bytes:8445 (8.4 KB)  lo        Link encap:Local Loopback             inet addr:127.0.0.1  Mask:255.0.0.0           inet6 addr: ::1/128 Scope:Host           UP LOOPBACK RUNNING  MTU:65536  Metric:1           RX packets:3870 errors:0 dropped:0 overruns:0 frame:0           TX packets:3870 errors:0 dropped:0 overruns:0 carrier:0           collisions:0 txqueuelen:0            RX bytes:314613 (314.6 KB)  TX bytes:314613 (314.6 KB)  wlan0     Link encap:Ethernet  HWaddr c0:38:96:6d:c4:83             inet addr:192.168.1.205  Bcast:192.168.1.255  Mask:255.255.255.0           inet6 addr: fe80::c238:96ff:fe6d:c483/64 Scope:Link           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1           RX packets:15240 errors:0 dropped:0 overruns:0 frame:0           TX packets:14627 errors:0 dropped:0 overruns:0 carrier:0           collisions:0 txqueuelen:1000            RX bytes:14410285 (14.4 MB)  TX bytes:2192744 (2.1 MB)  eth0      no wireless extensions.  wlan0     IEEE 802.11bgn  ESSID:"DIR-615"             Mode:Managed  Frequency:2.437 GHz  Access Point: 00:90:4C:08:00:0D              Bit Rate=150 Mb/s   Tx-Power=20 dBm              Retry short limit:7   RTS thr=2347 B   Fragment thr:off           Power Management:off           Link Quality=70/70  Signal level=-22 dBm             Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0           Tx excessive retries:0  Invalid misc:186   Missed beacon:0  lo        no wireless extensions.  Kernel IP routing table Destination     Gateway         Genmask         Flags Metric Ref    Use Iface 0.0.0.0         192.168.1.1     0.0.0.0         UG    400    0        0 wlan0 169.254.0.0     0.0.0.0         255.255.0.0     U     1000   0        0 wlan0 192.168.1.0     0.0.0.0         255.255.255.0   U     0      0        0 wlan0 PING google.com.Dlink (172.26.136.19) 56(84) bytes of data. 64 bytes from 19.136.26.172.in-addr.arpa (172.26.136.19): icmp_seq=1 ttl=249 time=102 ms  --- google.com.Dlink ping statistics --- 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 102.547/102.547/102.547/0.000 ms Totally real Galois extension of given degree Let $n≥1$ be an integer. I would like to prove (or disprove) the existence of a subfield $K \subset \Bbb R$ such that $K/\Bbb Q$ is Galois and has degree $n$.   It is easy to construct such a subfield for $n=2^k$: one  take $K=\Bbb Q(\sqrt 2, \sqrt 3, \sqrt 5, ..., \sqrt{p_k})\;$ where $p_k$ is the $k$-th prime number.  I found that the irreducible polynomial $x^3-6x+2 \in \Bbb Q[X]$ (Eisenstein's criterion with $p=2$) has three real roots, so its splitting field $K$ satisfies my conditions for $n=3$. Then I'm done with $n=3\cdot 2^k$ thanks to compositum of fields.  , a Galois extension of odd degree must be . In all cases, I don't know how to construct, in general or in particular cases ($n$ prime for instance), such a totally real Galois extension $K/\Bbb Q$ of degree $n$.  Thank you for your help! MLE for Poisson-binomial distribution I am looking for the maximum likelihood estimator (MLE) for the .  I understand the derivation of the MLE for a  and a , but I am unable to derive the MLE equation for the Poisson-binomial distribution. Superscript outside math mode So I've got the shout in my shouts list and I've unlocked all three parts of it, but I can't seem to be able to use it all, just the first part.  Am I missing something? I still have a quest for 'Learn the first word of Durnehviir's shout' but it's showing as me having already got it.  What gives? U.s. boiler / Burnham boiler alterations i have a 203ncl-tei2 boiler installed in danvers Massachusetts. Regular elevation. This boiler also has a failed tejurland (universal control) powerventer motor on it that is only humming, not spinning. Looked for a dead animal, or nest and checked for free spinning of the squirrel cage it was fine. Its installed 3 feet from outside wall on the verticle, (installed wrong also has 2 seperate 90° bends after the venter, not my issue but may have caused the motor to fail). Ontop of the boiler we have a factory automatic damper assy.   So the 2nd part of the problem is I noticed the tei in the model number and assumed this ment i should expect to see a tejurland "universal" power venter installed and i do. I assume because its a universal control unit thats where they went wrong. This unit is atleast 200$ cheaper here than the model burnham uses.  I call burnham and ask what the original power venter model number is and they tell me what some pros may already know, (i didnt), that the tei2 is actually (t)taco, (el)elivation, (2) 2 is 2,000 ft  .Note:he was not.100% sure about the el. He was definetly sure PV would be in the model number and it was not tejurland. There is no chimney on this house, never was. Power venter wall thimble outside is very old definetly older than the 1 year old motor that failed. Burnham also said this is not a boiler that can be converted to a powerventer which is sometging i do not understand. He said if it does not have pv in the model number it should not have one. I have in the past converted a boiler with a factory reccomended power venter after a customer lost the chimney. I called and got lucky they had a option for it. I do not remember manufacturer but do remember also seeing it in the install manual as an addendum or seperate manual.  Is this a fact?   Anyone have experience with this?   What are the ramifications of an elevated boiler installed at sea level?   If i can not find another awnser, i will havemto tell customer they need a new boiler or i will have to walk away.   Why do they not just make an orifice kit for elevated boilers to work properly at higher elevations? Is it because they have to add another section to the boiler so it can put out the same  b.t.u.?  I know there is a reason. Seems like smaller orifice would fix the air fuel ratio along with a regulator adjustment. Its to simple of an awnser knowing that manufacturers make a complete different boiler for higher elevations.   ! On my fully updated Ubuntu 18.04.3 system, audio doesn't work unless I switch between outputs. When I boot my PC, the right output (stereo speakers) is already selected by default, but there is no audio from Chromium, Firefox, VLC or any other program. However, the GNOME speakers test works. I can hear "front left" and "front right" from there, but no audio from other programs. In order to fix that, I can simply switch to another audio output (e.g. HDMI out) and then switch back to the stereo speakers, and the audio will magically work. Any idea why? It's not a big deal because it takes a couple of seconds to switch between outputs, but it's kind of annoying to do that after every reboot. What is the distribution of the sum of non i.i.d. gaussian variates? If $X$ is distributed $N(\mu_X, \sigma^2_X)$, $Y$ is distributed $N(\mu_Y, \sigma^2_Y)$ and $Z = X + Y$, I know that $Z$ is distributed $N(\mu_X + \mu_Y, \sigma^2_X + \sigma^2_Y)$ if X and Y are independent.  But what would happen if X and Y were not independent, i.e. $(X, Y) \approx N\big( (\begin{smallmatrix} \mu_X\\\mu_Y \end{smallmatrix}) , (\begin{smallmatrix} \sigma^2_X &amp;&amp; \sigma_{X,Y}\\ \sigma_{X,Y} &amp;&amp; \sigma^2_Y \end{smallmatrix}) \big) $  Would this affect how the sum $Z$ is distributed? This question aims to create an &quot;&quot;  of numerous questions that ask about determinants of specific matrices (I may have missed a few):              The general question of this type is  Let $A$ be a square matrix of rank$~1$, let $I$ the identity matrix of the same size, and $\lambda$ a scalar. What is the determinant of $A+\lambda I$?  A clearly very closely related question is  What is the characteristic polynomial of a matrix $A$ of rank$~1$? Creation parameters menu greyed out When adding a UV Sphere mesh in Blender 2.8, the creation parameters menu on the bottom left of the attached image for this UV Sphere seems to be greyed out. Any idea why this might be? Thanks. Grid search vs. random search for hyperparameter tuning I am interested in comparing the computational cost of grid search vs. random search algorithm for hyperparameter tuning. Is random search computationally less expensive then grid search? Is there an article/paper that talks about this topic? Thank you, How do I remove a property from a JavaScript object? Say I create an object as follows: let myObject = {   &quot;ircEvent&quot;: &quot;PRIVMSG&quot;,   &quot;method&quot;: &quot;newURI&quot;,   &quot;regex&quot;: &quot;^http://.*&quot; };  How should I remove the property regex to end up with new myObject as follows? let myObject = {   &quot;ircEvent&quot;: &quot;PRIVMSG&quot;,   &quot;method&quot;: &quot;newURI&quot; }; How does one parse XML files?