I have the Realtek rtl8723be driver on my HP-Pavillion Notebook.  While installing Ubuntu 18.04 LTS through plug-n-play option, I tried the following commands before actual installation:  sudo modprobe -r rtl8723be sudo modprobe rtl8723be ant_sel=2   and the wifi was working just fine.  But after installation alongside Windows 10, somehow the wifi stopped working properly, and now only wifi networks very close to the device appear.  I tried installing realtek software from  as mentioned in the README. But still no progress.   I even tried changing ant_sel parameters, then saving them to my /etc/modprobe.d/rtl8723be.conf and then performing a cold boot. But still no progress.  I also tried installing from , but I got errors.  sudo lshw -class network   *-network                         description: Wireless interface        product: RTL8723BE PCIe Wireless Network Adapter        vendor: Realtek Semiconductor Co., Ltd.        physical id: 0        bus info: pci@0000:08:00.0        logical name: wlo1        version: 00        serial: 70:77:81:bf:a7:b9        width: 64 bits        clock: 33MHz        capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless        configuration: broadcast=yes driver=rtl8723be driverversion=4.15.0-36-generic firmware=N/A latency=0 link=no multicast=yes wireless=IEEE 802.11        resources: irq:18 ioport:5000(size=256) memory:c6100000-c6103fff   *-network        description: Ethernet interface        product: RTL8101/2/6E PCI Express Fast/Gigabit Ethernet controller        vendor: Realtek Semiconductor Co., Ltd.        physical id: 0        bus info: pci@0000:09:00.0        logical name: eno1        version: 0a        serial: 3c:a8:2a:ba:12:6f        size: 10Mbit/s        capacity: 100Mbit/s        width: 64 bits        clock: 33MHz        capabilities: pm msi pciexpress msix bus_master cap_list ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd autonegotiation        configuration: autonegotiation=on broadcast=yes driver=r8169 driverversion=2.3LK-NAPI duplex=half firmware=rtl8107e-2_0.0.2 02/26/15 latency=0 link=no multicast=yes port=MII speed=10Mbit/s        resources: irq:19 ioport:4000(size=256) memory:c6004000-c6004fff memory:c6000000-c6003fff   *-network        description: Ethernet interface        physical id: 3        logical name: enp0s20u2        serial: ea:f8:17:e8:82:30        capabilities: ethernet physical        configuration: broadcast=yes driver=rndis_host driverversion=22-Aug-2005 firmware=RNDIS device ip=192.168.42.6 link=yes multicast=yes   Can anyone suggest what to do now?
I have a HP 14-AN001NA laptop. It came with Windows 10 installed on which the Wi-Fi worked fine anywhere in the house.   However I removed Windows 10 and installed Ubuntu 16.04 instead and since I have had terrible Wi-Fi anywhere aside from about three foot away from the router. I don't know if it's relevant but my Wi-Fi is not called wlan0 but wlo1 for some reason (I didn't change it).  When running lspci -knn | grep Net -A3     I get the following output:  05:00.0 Network controller [0280]: Realtek Semiconductor Co., Ltd. RTL8723BE PCIe Wireless Network Adapter [10ec:b723] DeviceName:   Subsystem: Hewlett-Packard Company RTL8723BE PCIe Wireless Network Adapter [103c:81c1] Kernel driver in use: rtl8723be Kernel modules: wl, rtl8723be
For a lot of questions here on TeX.SE and on other fora regarding MiKTeX, it turns out that the underlying problem actually lies in the not understood distinction between administrative and user modes. So let me ask these questions:  What’s the difference between administrative and user mode in MiKTeX, and in which situation should I use either one of these modes? Doing heatmap from line data in QGIS? MatrixPlot with Tooltips Why won't SparseArray let me store values with the head List? Should seemingly arbitrary things like "play piano for Church" or "intramural badminton" go on M.S. or PhD applications in sciences/engineering? And if they should, I assume that these things should go on a resume under something like "Activities and Community Service". I mean I consider being able to sight read music to play at my Church as a significant feat (how many people can do that?) and might sway one person on an admissions committee if he or she enjoys music and understands how hard one must have worked to accomplish this.   Badminton?.... perhaps not so much How quickly does the Ultimate Meter fill up? Boats from Manaus, Brazil to Leticia, Colombia? I've heard of and met a few people who have done this route, and I hope to do it at the end of this year or early next year.  However, the descriptions were mostly sketchy, and I'm wondering if it's a regularly scheduled service, or more ad-hoc.  So I guess the question is, how can I find out which boats go from Manaus to Leticia, and when they go?  Ideally this wouldn't be a tour, but a 'locals' boat. Search and replace multiple values with multiple/different values in PHP5? Interpretation of R's lm() output The help pages in R assume I know what those numbers mean, but I don't. I'm trying to really intuitively understand every number here. I will just post the output and comment on what I found out. There might (will) be mistakes, as I'll just write what I assume. Mainly I'd like to know what the t-value in the coefficients mean, and why they print the residual standard error.   Call: lm(formula = iris$Sepal.Width ~ iris$Petal.Width)  Residuals:      Min       1Q   Median       3Q      Max  -1.09907 -0.23626 -0.01064  0.23345  1.17532    This is a 5-point-summary of the residuals (their mean is always 0, right?). The numbers can be used (I'm guessing here) to quickly see if there are any big outliers. Also you can already see it here if the residuals are far from normally distributed (they should be normally distributed).  Coefficients:                  Estimate Std. Error t value Pr(&gt;|t|)     (Intercept)       3.30843    0.06210  53.278  &lt; 2e-16 *** iris$Petal.Width -0.20936    0.04374  -4.786 4.07e-06 *** --- Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1    Estimates $\hat{\beta_i}$, computed by least squares regression. Also, the standard error is $\sigma_{\beta_i}$. I'd like to know how this is calculated.  I have no idea where the t-value and the corresponding p-value come from. I know $\hat{\beta}$ should be normal distributed, but how is the t-value calculated?  Residual standard error: 0.407 on 148 degrees of freedom   $\sqrt{ \frac{1}{n-p} \epsilon^T\epsilon }$, I guess. But why do we calculate that, and what does it tell us?  Multiple R-squared: 0.134,  Adjusted R-squared: 0.1282    $ R^2 = \frac{s_\hat{y}^2}{s_y^2} $, which is $ \frac{\sum_{i=1}^n (\hat{y_i}-\bar{y})^2}{\sum_{i=1}^n (y_i-\bar{y})^2} $. The ratio is close to 1 if the points lie on a straight line, and 0 if they are random.  What is the adjusted R-squared?  F-statistic: 22.91 on 1 and 148 DF,  p-value: 4.073e-06    F and p for the whole model, not only for single $\beta_i$s as previous. The F value is $ \frac{s^2_{\hat{y}}}{\sum\epsilon_i} $. The bigger it grows, the more unlikely it is that the $\beta$'s do not have any effect at all. Proof that Epicycloids are Algebraic Curves? Epicycloids are most commonly described by the parametric equations,   $x(t) = (R + a)\cos(t) – a \cos \left(\frac{R + a}{a} t \right),$  $y(t) = (R + a)\sin(t) – a \sin \left(\frac{R + a}{a} t \right).$  Where $R$ is the radius of the fixed circle and $a$ is the radius of the rolling circle.   With $R = ka$ we also have,   $x(t) = a[(k + 1)\cos(t) - \cos((k + 1)t)],$  $y(t) = a[(k + 1)\sin(t) - \sin((k + 1)t)].$  Several books discussing epicycloids mention that if the ratio of the radii of the circles $\left( \frac{R}{a} = k \right)$ is rational, then they are algebraic curves. However, I’ve only been able to find the Cartesian equations for the cardioid, nephroid and ranunculoid. With the cardioid being,   $(ax + x^2 + y^2)^2 = a^2(x^2 + y^2).$   The nephroid,   $(-4a^2 + x^2 + y^2)^3 = 108a^4y^2.$  And the ranunculoid,   $-52521875a^{12} – 1286250a^{10} (x^2 + y^2) – 32025a^8 (x^2 + y^2)^2 + 93312a^7 (x^5 – 10x^3y^2 + 5xy^4) – 812a^6 (x^2 + y^2)^3 – 21a^4 (x^2 + y^2)^4 – 42a^2(x^2 + y^2)^5 + (x^2 + y^2)^6 = 0.$  Clearly this doesn’t cover all epicycloids where $\frac{R}{a}$ is rational.   What is the proof that shows that epicycloids, where the ratio of the radii are rational, are algebraic curves? How to show $a,b$ coprime to $n\Rightarrow ab$ coprime to $n$? Let $a,b,n$ be integers such that  $\gcd(a,n)=\gcd(b,n)=1$. How to show that $\gcd(ab,n)=1$?   In other words, how to show that if two integers $a$ and $b$ each have no non-trivial common divisor with and integer $n$, then their product does no have a non-trivial common divisor with $n$ either.     This is a problem that is an exercise in my course.   Intuitively it seems plausible and it is easy to check in specific cases but how to  give an actual proof is not obvious. I'm looking for an algorithm which when given a latitude and longitude pair and a vector translation in meters in Cartesian coordinates (x,y) would give me a new coordinate. Sort of like a reverse Haversine. I could also work with a distance and a heading transformation, but this would probably be slower and not as accurate. Ideally, the algorithm should be fast as I'm working on an embedded system. Accuracy is not critical, within 10 meters would be good. For the following block of code:  For I = 0 To listOfStrings.Count - 1     If myString.Contains(lstOfStrings.Item(I)) Then         Return True     End If Next Return False   The output is:  Case 1:  myString: C:\Files\myfile.doc listOfString: C:\Files\, C:\Files2\ Result: True   Case 2:  myString: C:\Files3\myfile.doc listOfString: C:\Files\, C:\Files2\ Result: False   The list (listOfStrings) may contain several items (minimum 20) and it has to be checked against a thousands of strings (like myString).  Is there a better (more efficient) way to write this code? How to prove that $A_5$ has no subgroup of order 30? I need to show that $A_5$ has no subgroup of order 30. Any ideas? L1 regression estimates median whereas L2 regression estimates mean? how does the circuit of a basic Variable speed electric drill work? i am trying to 'automate' the control of an electric drill motor that im taking from a garden variety Variable Speed drill (from Harbor Freight)  it has a universal AC motor which I basically undertand and a DPDT switch to reverse direction and a triac citcuit to vary speed    Question 1 . i see 4 wires going to the 'field/Stator coil(s)'. Are there 2 seperate field/stator coils here? is this to provide low/high power.  I think in theory , you only need 1 coil with 2 wires and that coil is wired in series with the brushes... is that right?   how does this circuit work with 2 coils.  Question 2 . how does this variable speed circuit work.  is the wiring diagram correct (it doesnt show a variable resistor and it doesnt show what drives the control input of the traic? why are there two switches in the thing? does switch 2 close at high speed and thus shunt around the triac?  please see the attached 4 diagrams How does water evaporate if it doesn't boil? When the sun is out after a rain, I can see what appears to be steam rising off a wooden bridge nearby. I'm pretty sure this is water turning into a gas.  However, I thought water had to reach 100 degrees C to be able to turn into a gas.  Is there an edge case, for small amounts of water perhaps, that allows it to evaporate? What's the intuition behind "stiff systems"? I would like to know if there is some way to share a variable or an object between two or more Servlets, I mean some "standard" way. I suppose that this is not a good practice but is a easier way to build a prototype.  I don't know if it depends on the technologies used, but I'll use Tomcat 5.5    I want to share a Vector of objects of a simple class (just public attributes, strings, ints, etc). My intention is to have a static data like in a DB, obviously it will be lost when the Tomcat is stopped. (it's just for Testing) Why can't I connect to Pokemon Go via mobile data?