Stopping Mathematica from reordering expressions
Returning an unevaluated expression with values substituted in
CSS Margin Collapsing So essentially does margin collapsing occur when you don't set any margin or padding or border to a given div element? "R cannot be resolved to a variable"? How do I dynamically invoke a class method in PHP? How can I dynamically invoke a class method in PHP? The class method is not static. It appears that   call_user_func(...)   only works with static functions?  Thanks. Character of the subobject classifier in the topos of $\mathbf{M}$-sets. I have a file with values organized in columns, and separated by commas, as in the file below:   324,01,1,113333600000,1,, 016,01,1,134954200000,1,, 770,01,1,109069200000,1,, 853,01,1,111518800000,1,,   When I use the following awk command, the delimiter is being changed from commas to spaces   Code:  awk -F, '{$4=$4/1024}{print $0}'   The output becomes:   324 01 1 110677343.75 1   016 01 1 131791210.93 1   770 01 1 106512890.62 1   853 01 1 108905078.12 1    How can I change the value of the field without changing the delimiter? Stargate - Destiny's Gate Address from Icarus base Simple question - What is the address they dial to connect with the Ancient ship Destiny in Stargate Universe from Icarus base.  I have found the address on  - however they have an unconfirmed order, and not sure of the validity of this.  Any help deciphering the above would be great! Repair disk from single user mode (fsck fails) How to switch between virtual console and GUI in Ubuntu? I wanted to see what key functions would allow me to switch between the two. G-test vs Pearson's chi-squared test How can I avoid Java code in JSP files, using JSP 2? Terminology of the sequences of promoters in relation to DNA strands I'm studying molecular biology and I'm trying to understand an experiment which shows the importance of promoters in the relative transcription level (RT). The image below comes from Rolf Knippers' book "Molekulare Genetik" (8th edition).    The legend says (among other things):     Die erste Zeile gibt die normale "Wildtyp"-Sequenz der 5'-flankierenden Region wieder.   Which, in english, means something like:     The first line repeats the normal wild-type sequence of the 5' flanking region.   The column on the right gives the relative transcription (RT) level, 1.0 being the highest possible level of transcription. As we can see, the lines where some parts of the "5' region" have been deleted give quite low RT levels, since some regions of the promoter are missing.  My questions are the following:  1) According to  and , I understand that RNA polymerase reads and uses both coding and non-coding strands in order to synthesize RNA. Therefore, how did they manage to use the sequences strands regions had been deleted to make a polymerase "read them" and perform transcription?  2) If the polymerase reads the template strand in the 3' -> 5' sense, shouldn't we talk of "ATAT box" or "TAAC box" instead of "TATA" or "CAAT" boxes? Does it mean that the "promoter" regions they are using on the graphic above are actually on the coding strand?  Thanks a lot for your help. Second law of Newton for variable mass systems Frequently I see the expression  $$F = \frac{dp}{dt} = \frac{d}{dt}(mv) = \frac{dm}{dt}v + ma,$$ which can be applied to variable mass systems.  But I'm wondering if this derivation is correct, because the second law of Newton is formulated for point masses.   Furthermore if i change the inertial frame of reference, only $v$ on the right side of the formula $F = \frac{dm}{dt}v+ma$ will change, meaning that $F$ would be dependent of the frame of reference, which (according to me) can't be true.   I realize there exists a formula for varying mass systems, that looks quite familiar to this one, but isn't exactly the same, because the $v$ on the right side is there the relative velocity of mass expulsed/accreted. The derivation of that formula is also rather different from this one.   So my question is: is this formula, that I frequently encounter in syllabi and books, correct? Where lies my mistake. I have an Asus UL30JT. It has Nvidia Optimus technology which I am not really interested in. I currently rarely use this laptop with it being connected to power. And I want to be able to play video at high res, play games and do some OpenCL coding.  In the BIOS I switched it to NVIDIA only (non windows 7). Previously, this worked just fine, using the nvidia driver.  After upgrading everything was broken. I have added nomodeset and blacklist.nouveau=1 as kernel options. The nvidia drivers install without error. However they are not found/used.  jockey-text -l kmod:nvidia_310_updates - nvidia_310_updates (Proprietary, Enabled, Not in use) kmod:nvidia_304_updates - NVIDIA binary Xorg driver, kernel module and VDPAU library (Proprietary, Disabled, Not in use) kmod:nvidia_313_updates - NVIDIA binary Xorg driver, kernel module and VDPAU library (Proprietary, Disabled, Not in use) kmod:nvidia_310 - NVIDIA binary Xorg driver, kernel module and VDPAU library (Proprietary, Disabled, Not in use) kmod:nvidia_304 - NVIDIA binary Xorg driver, kernel module and VDPAU library (Proprietary, Disabled, Not in use)   Trying to load the module manually fails as well.  sudo modprobe nvidia FATAL: Module nvidia not found.   Xorg.0.log show the following:  [    12.028] Loading extension GLX [    12.028] (II) LoadModule: "nvidia" [    12.037] (WW) Warning, couldn't open module nvidia [    12.037] (II) UnloadModule: "nvidia" [    12.037] (II) Unloading nvidia [    12.037] (EE) Failed to load module "nvidia" (module does not exist, 0) [    12.037] (==) Matched nvidia as autoconfigured driver 0 [    12.037] (==) Matched nouveau as autoconfigured driver 1 [    12.037] (==) Matched vesa as autoconfigured driver 2 [    12.037] (==) Matched modesetting as autoconfigured driver 3 [    12.038] (==) Matched fbdev as autoconfigured driver 4 [    12.038] (==) Assigned the driver to the xf86ConfigLayout [    12.038] (II) LoadModule: "nvidia" [    12.038] (WW) Warning, couldn't open module nvidia [    12.038] (II) UnloadModule: "nvidia" [    12.038] (II) Unloading nvidia [    12.038] (EE) Failed to load module "nvidia" (module does not exist, 0) [    12.038] (II) LoadModule: "nouveau" [    12.039] (WW) Warning, couldn't open module nouveau   I have installed the kernel headers, of the correct kernel. I verified that the kernel options are in the grub configuration. I have purged all nvidia packages and tried to reinstall (multiple times...)  Currently I am at a loss. I have checked the following question:  But nothing there worked for me. rand() returns same values when called within a single function How long would the conference be for? I want to know if this is grammatically correct " How long would the conference be for?". \sum caused \sqrt to not be slanted vertical lines in matrix using tikz package my problem is interconnected to my two previous posts ( and) and i've tried to incorporate answers into solution but without success.   My task is this matrix multiplication with added description:   and my so far code follows:  \documentclass{article} \usepackage{tikz,amsmath}  \begin{document} \begin{tikzpicture} \node[minimum height=0cm,minimum width=2cm] (m) {}; \path[shade,draw] (0,2) -- (0,5) -- (3,5) -- (3,0); \draw (0,0) --(0,5); \draw (3,0) --(0,2); \draw (3,0) --(3,5); \node (r11) at ([xshift=0.6cm,yshift=4cm]m.south) {$S_{11}$}; \node (r11) at ([xshift=2.5cm,yshift=4cm]m.south) {$S_{12}$}; \node (r11) at ([xshift=2.5cm,yshift=2.15cm]m.south) {$S_{22}$}; \node (r11) at ([xshift=0.6cm,yshift=2.15cm]m.south) {$S_{21}$}; \node (r11) at ([xshift=0.6cm,yshift=2.6cm]m.south) {$--------------$}; \node (r11) at ([xshift=0.6cm,yshift=1.5cm]m.south) {$--------------$}; \end{tikzpicture} \[ \begin{bmatrix} \begin{equation}        wn_{1}           \\[0.3em]        wn_{2}       \end{bmatrix}  \]  \end{document}       with following output:      I am not able to add vertical line and nodes and incorporate the matrix into document (vector that follows behind the matrix is not centered). Problem with nodes and incorporation is the same as in . I am unable to find the link for downloading Ubuntu 16.04 onto my   desktop/laptop. I am able to see the link only for 18.04, but I need 16.04. Images instead of radio buttons or dropdown list? There is a  being thrown out of a flask, literally hovering out of the container  My question is how detailed a physical explanation of this phenomenon we have?  Question: More precisely, if we used the best available mechanical physics simulator software, and we tried to simulate this behavior, would the software be able to reproduce the effect or not? My guess is not but I would like to know why not.  Or do we have to content ourselves only with handwaved explanations? I am from the school of thought that you don't understand physics until you have a reasonable certainty that you can reproduce the physics in a computer.