Optimistic way of checking null references in java
Avoiding NullPointerException in Java
How do I determine the size of my array in C?   That is, the number of elements the array can hold? How do you use Excel server-side? A client wants to "Web-enable" a spreadsheet calculation -- the user to specify the values of certain cells, then show them the resulting values in other cells.  (They do NOT want to show the user a "spreadsheet-like" interface. This is not a UI question.)  They have a huge spreadsheet with lots of calculations over many, many sheets.  But, in the end, only two things matter -- (1) you put numbers in a couple cells on one sheet, and (2) you get corresponding numbers off a couple cells in another sheet.  The rest of it is a black box.  I want to present a UI to the user to enter the numbers they want, then I'd like to programatically open the Excel file, set the numbers, tell it to re-calc, and read the result out.  Is this possible/advisable?  Is there a commercial component that makes this easier?  Are their pitfalls I'm not considering?  (I know I can use Office Automation to do this, but I know it's not recommended to do that server-side, since it tries to run in the context of a user, etc.)  A lot of people are saying I need to recreate the formulas in code.  However, this would be staggeringly complex. I have a character playing a multiclass Barbarian/Monk. Does the resistance from rage combine with Deflect Missiles to negate the damage and make the reaction attack? What is the best way to remove texture from a scanned textured photo paper? I have a bunch of scanned old family photos where the photo paper has a texture. Unfortunately, the texture of the photo scans quite well. What is the best way to remove the texture?  (Photoshop CS5) Should I install programs from a source tarball (`.tar.gz`), from the Ubuntu Software Centre, or from elsewhere? How to install apps which require a newer version of iOS on a 1st gen. iPad? I have read in a book that the limit of the ratio of consequent Fibonacci numbers is the golden ratio. However, it was just mentioned thus not justified. So, my question is how would you derive the following limit: $$\lim_{x\to\infty}{\frac{F_n}{F_{n+1}}}=?$$ Where $F_n$ is the nth Fibonacci number? Mach-O 64-bit format does not support 32-bit absolute addresses. NASM Accessing Array Is a variable/arbitrary element a precisely defined mathematical object? Can someone please explain this weird Pygame importing convention? I am trying to assign an image texture to an Image Texture node in 2.80. Very simple script - I'm just starting to learn how this stuff works.  This is what I have. It creates an image and and IT node, but it doesn't assign the one to other. Can anybody help? I've searched around, but can't find it in another question.  import bpy  #create blank image bpy.ops.image.new(name="TestImg", width=1024, height=1024)  #add image texture to object, to hold baked lighting mat = bpy.context.view_layer.objects.active.active_material image_node = mat.node_tree.nodes.new('ShaderNodeTexImage')  #assign image to image texture node image_node.image = "TestImg"   Thanks in advance. I have a beamer frame with about 150 slides on it.  I want article and handout mode to only show frame 92.    Reading section 8.6.2 of the beamer manual it seems like I should be able to do something like  \begin{frame}&lt;handout:92&gt; ... \end{frame}   but that seems to have no effect--all 150 slides are set in handout mode, overlaying (making the result unreadable).  I have gotten the effect I want by taking all commands within the frame that have an overlay specification and adding "| handout:0" to make them not appear in handout mode.  Annoying, but works.  But for my 150-slide frame the different slides are generated by a PGF \foreach loop so I can't code slide 92 differently from the rest.  But can I do this at the frame's overlay specification?  It seems that the frame's overlay spec really acts differently from other commands.  If I only do  \begin{frame}&lt;92&gt;...\end{frame}   then I get only slide 92 in beamer mode but all slides in article or handout mode. I have 2 graphics cards (Tesla k10, K40) in my supermicro SuperServer (7047GR-TPRF). I installed Ubuntu Server 14.04, but when I install cuda or Nvidia graphics driver (version 311 or 340), my Ubuntu desktop hangs on login. Brightness is reset to maximum on every restart The brightness of my laptop is reset to max on every restart. I tried the solution provided at  but had no luck.   This command   cat /sys/class/backlight/acpi_video0/max_brightness   Returns   cat: /sys/class/backlight/acpi_video0/max_brightness: No such file or directory   Then I found that I don't have a folder named acpi_video0, but a folder called intel_backlight:    Every time I increase or decrease the brightness using the brightness control keys, the values in brightness and actual_brightness get updated.  Is there any method I could follow to set the brightness to a fixed value on every boot and vary it as and when I need it using the brightness control keys? Suppose that an entire function $f(z)$ satisfies $\left|f(z)\right|\leq k\left|z\right|^n$ for sufficiently large $\left|z\right|$, where $n\in\mathbb{Z^+}$ and $k&gt;0$ is constant. Show that $f$ is a polynomial of degree at most $n$. One runtime platform provides an API that supplies PKCS#5 padding for block cipher modes such as ECB and CBC. These modes have been defined for the triple DES, AES and Blowfish block ciphers. The other platform API only provides PKCS#7 padding.  Are PKCS#5 padding and PKCS#7 padding compatible? How to check if PHP array is associative or sequential? PHP treats all arrays as associative, so there aren't any built in functions. Can anyone recommend a fairly efficient way to check if an array contains only numeric keys? Basically, I want to be able to differentiate between this: $sequentialArray = [     'apple', 'orange', 'tomato', 'carrot' ];  and this: $assocArray = [     'fruit1' =&gt; 'apple',     'fruit2' =&gt; 'orange',     'veg1' =&gt; 'tomato',     'veg2' =&gt; 'carrot' ]; Layout selector missing I am giving a LaTeX course and have the idea to let the students find and solve problems within a few documents. Basically they shall learn how to create minimal examples and read error messages.  However, currently I have no document with 'typical' errors around.  If someone has such examples from him- or herself or within this forum I would like to have the code or link. It does not matter if its short or long. It should just be enough to let the students play with it for some minutes. How can I bypass Activation Lock?