I'm trying to make a walk cycle on a character, but there's a problem. When I loop the walkcycle, the steps kind of ease in and out, making the feet slide even when the character is moving at a constant speed.  Could somebody please point out how to fix this issue? Is there a process to create a walkcycle that ensures that the feet move at a constant speed while they're on the ground?  EDIT This is different from the "duplicate" question in that I am not looking for a general answer on how to make a movement be steady, but specifically how to work with a walk cycle.
When I make an animation, it always starts out slow, then speeds up, then slows down at the end.  I cannot figure out how to fix this.
Schengen Visa Application: what are some helpful tips for preparing? Why do we use von Neumann ordinals and not Zermelo ordinals? Why do we use von Neumann ordinals, $$ 0 = \emptyset $$ $$ n+1 = n \cup \{n\} $$  and not Zermelo ordinals? $$ 0 = \emptyset $$ $$ n+1 = \{ n \} $$ It's so cool that the notification reminds you of the colour of badge you've earned. But I am a little puzzled by the symbols:      Is it feasible to use the symbol from the earned site? At the moment it uses the symbol from the site I happen to be on (as you can see by looking to the left of the dropdown in each case.) Seem to have lost 4 Silver badges and 10 Bronze badges How to correctly specify coordinate system? Using QGIS v. 1.9 (1.7 does not seem to be available for Ubuntu Linux 12.04), do the following:   Create new project, specify coordinate system by clicking on button in bottom right hand corner, enable on the fly CRS transformation, set projection to WGS 84 / UTM Zone 18S. Pass mouse over project window and UTM coordinates appear in coordinates window in status bar at the bottom. Add delimited text layer in decimal degrees. When asked for projection, specify same projection as in (1). Points in the layer are plotted but, mousing over the map, the coordinates in the coordinates window are now in decimal degrees (even though the projection is set to UTM).   Is there something I am missing here? I have tried doing this in so many ways, so many times, but the result is always the same. I seem to be setting the projection correctly but only decimal degrees show in the coordinates window.  With thanks, Martin Prove $\sup(f+g) \le \sup f + \sup g$ Suppose $D$ is a nonempty bounded subset of reals. Let $f:D \to \mathbb R$ and $g:D \to \mathbb R$. Define $(f+g)(x)=f(x)+g(x)$. Prove $\sup(f+g)(D) \le \sup f(D) + \sup g(D)$ (also prove that $\sup (f+g)$ exists).   I understand why this is the case, just not how to prove it. Left side is pretty much $\sup  (f(x)+g(x))$ and right side is $\sup (f(x) + g(y))$ for $x,\,y \in D$. Basically $f+g$ has to use the same variable and $f(D)+g(D)$ use different ones. But I don't know how to go about proving this.     The second part of the question is to find a specific example where strict inequality holds.    Let $D=\{a,b\}$ and $f: a \to 1,\, b\to 0, \,g: a \to 0,\, b\to 1$. $\sup f(D) = 1,\, \sup g(D) = 1,\, \sup f(D) + \sup g(D) = 2.$ $\sup (f+g)(D) = 1$ (if we choose a, $f+g = 1+0,\, b,\, f+g=0+1$). I have a shapefile with date in a string field. I create a new field with date type and use the calculator to make the conversion. But the result only provide the date part, the time part is removed. Even when the preview show the correct conversion.  Here you can see the original string field time and the result date time2. And the use of the conversion function to_datetime() and the preview result at the end    If you go to the layer properties you can change the edit mode to date/time. Then if go to the data and try to edit time2 you get the current date/time. So is possible save date and time in the same field. But the update tool still doesn't work as expected      As J.R said. Even when you can change QGIS edit to allow Date/Time the save to shapefile will discard the time. Truncate a string to first n characters of a string and add three dots if any characters are removed Proof $1+2+3+4+\cdots+n = \frac{n\times(n+1)}2$ Apparently $1+2+3+4+\ldots+n = \dfrac{n\times(n+1)}2$.  How? What's the proof? Or maybe it is self apparent just looking at the above?   PS: This problem is known as "The sum of the first $n$ positive integers". Applying for a USA B1/B2 Visa for an alien resident in Germany I hold an EU Blue Card and an Indian Passport and have submitted a paper to a conference in the USA due to occur in September 2019. The Blue Card will expire in August 2019 but have already obtained an extension for the same.  In order to present the paper in the conference I need to apply for a B1/B2 visa for the USA and not sure if I may be allowed to apply for one in Germany since I am not a German Citizen.  Are there any specific documents that I might need in order to apply for the B1/B2 Visa since I am not a citizen of the country where I am actually applying? I have a long sequence of hex digits in a string, such as      000000000000484240FA063DE5D0B744ADBED63A81FAEA390000C8428640A43D5005BD44   only much longer, several kilobytes.  Is there a builtin way to convert this to a bytes object in python 2.6/3? Activate Rigid Body Physics at certain time? I've been trying to make a wrecking ball smash through a figure of sorts, not really sure what exactly but I made an example. The problem I'm having is that the figure does indeed fall apart, but I would like it to stay put together until the ball hits it. I achieved this by using Cell Fracture on the figure and just using Rigid Body. Again, I just need a way for the figure to stay still until hit by the ball, and then have all of its pieces come apart. Is there a way to make sure that a deleted file can not be recovered?   As you know, deleting a file by pressing shift-del or using trash doesn't mean that file is gone forever. It resides somewhere in the computer.  In day to day life, law enforcement or thieves use recovery programs to reveal our private data or something else.   They can recover all data that resides on hard disk, in RAM, and even USB.  To protect us from these people, what should one do? Which program should one use?  Note: I don't want an answer like first use a recovery program then erase that file with shred. With just one program, I want to erase all unused/deleted files on my computer. Can I use HMAC-SHA1 in counter mode to make a stream cipher? Say I have an embedded device which is only capable of doing HMAC-SHA1 transformations (that device is, in fact, a YubiKey).  Would it be secure to feed it like a block cipher in counter mode to get a random pad suitable as an stream cipher?  Of course, I'm talking about not repeating the counter value ever to encrypt data (so this construction would also need some random IV or treating the counter value as a nonce forever). Why am I asked for a credit card number to download a free app? I  want to download free app in my iPod touch device and i have the following doubts.  Kindly resolve me doubts.   when i try to download it asks my credit card security number. since i am trying to download free app , why do i need to provide my credit card security code? Will i be debited for downloading the free app from app store?   I cant able to find any information regarding this on apple.  Please provide me some references about this from apple and please resolve my doubts.  Thanks a lot. My computer is loud: How do I tell which fan is the issue? On my new computer, my fan(s) is/are plain LOUD! Using SpeedFan, I find that my temps are all under 32 degrees C under my normal use (IDK how accurate that is but the CPU itself says 27 C).  The fan doesn't sound unbalanced and it isn't making sounds in rhythm (Not the usual rrrrrrrRRRRRR... rrrrrrrRRRRRR... rrrrrrrRRRRRR... rrrrrrrRRRRRR), just a constant fan. I am thinking about oiling the fans, but I can't decide if it is the PSU fan or a case fan or the CPU fan. If it's the CPU fan I will most likely just replace that with a quiet fan. How can I tell which fan is making the noise (if not multiple)?  One thing that I am thinking may be the problem is my CPU fan isn't PWM so would swapping that out help? There is no "linear voltage" or etc thing in BIOS so I think it may be running at full speed. Also, I could have too much airflow because it is also making a whistling noise that you can hear close to it that sounds like when I accedentially put part of the side cover over my floor vent to get it out of the way. Can't clean a full /boot because of unmet dependencies I got an error message explaining my /boot is full. trying to clean up old image files always seems to fail because of disk full errors or dependency errors. Could someone explain where I’m going wrong.   $ sudo apt-get autoremove Reading package lists... Done Building dependency tree        Reading state information... Done You might want to run ‘apt-get -f install’ to correct these. The following packages have unmet dependencies.  linux-image-extra-3.13.0-44-generic : Depends: linux-image-3.13.0-44-generic but it is not installed  linux-image-extra-3.13.0-45-generic : Depends: linux-image-3.13.0-45-generic but it is not installed  linux-image-generic : Depends: linux-image-3.13.0-45-generic but it is not installed E: Unmet dependencies. Try using -f.  $ ls /boot abi-3.13.0-32-generic         initrd.img-3.13.0-43-generic abi-3.13.0-36-generic         lost+found abi-3.13.0-37-generic         memtest86+.bin abi-3.13.0-39-generic         memtest86+.elf abi-3.13.0-40-generic         memtest86+_multiboot.bin abi-3.13.0-43-generic         System.map-3.13.0-32-generic config-3.13.0-32-generic      System.map-3.13.0-36-generic config-3.13.0-36-generic      System.map-3.13.0-37-generic config-3.13.0-37-generic      System.map-3.13.0-39-generic config-3.13.0-39-generic      System.map-3.13.0-40-generic config-3.13.0-40-generic      System.map-3.13.0-43-generic config-3.13.0-43-generic      vmlinuz-3.13.0-32-generic grub                          vmlinuz-3.13.0-36-generic initrd.img-3.13.0-32-generic  vmlinuz-3.13.0-37-generic initrd.img-3.13.0-36-generic  vmlinuz-3.13.0-39-generic initrd.img-3.13.0-37-generic  vmlinuz-3.13.0-40-generic initrd.img-3.13.0-39-generic  vmlinuz-3.13.0-43-generic initrd.img-3.13.0-40-generic   I used   kernelver=$(uname -r | sed -r 's/-[a-z]+//') dpkg -l linux-{image,headers}-"[0-9]*" | awk '/ii/{print $2}' | grep -ve $kernelver   to get   linux-headers-3.13.0-32 linux-headers-3.13.0-32-generic linux-headers-3.13.0-36 linux-headers-3.13.0-36-generic linux-headers-3.13.0-37 linux-headers-3.13.0-37-generic linux-headers-3.13.0-39 linux-headers-3.13.0-39-generic linux-headers-3.13.0-40 linux-headers-3.13.0-40-generic linux-headers-3.13.0-44 linux-headers-3.13.0-44-generic linux-headers-3.13.0-45 linux-headers-3.13.0-45-generic linux-image-3.13.0-32-generic linux-image-3.13.0-36-generic linux-image-3.13.0-37-generic linux-image-3.13.0-39-generic linux-image-3.13.0-40-generic   Then picking the first image to remove   $ sudo apt-get purge linux-image-3.13.0-32-generic Reading package lists... Done Building dependency tree        Reading state information... Done You might want to run 'apt-get -f install' to correct these: The following packages have unmet dependencies.  linux-image-extra-3.13.0-32-generic : Depends: linux-image-3.13.0-32-generic but it is not going to be installed  linux-image-extra-3.13.0-44-generic : Depends: linux-image-3.13.0-44-generic but it is not going to be installed  linux-image-extra-3.13.0-45-generic : Depends: linux-image-3.13.0-45-generic but it is not going to be installed  linux-image-generic : Depends: linux-image-3.13.0-45-generic but it is not going to be installed E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution). If I know the index node (inode) of a file, but I don't know its path (or any of its paths), is it possible to create a hard link to that inode directly?  I could find the file using sudo find / -inum 123546 and then create a hardlink, but that would be way too slow for my application.  N.B. I'm using an ext4 filesystem. Why isn't it $E \approx 27.642 \times mc^2$? Why is it that many of the most important physical equations don't have ugly numbers (i.e., "arbitrary" irrational factors) to line up both sides?   Why can so many equations be expressed so neatly with small natural numbers while recycling a relatively small set of physical and mathematical constants?  For example, why is mass–energy equivalence describable by the equation $E = mc^2$ and not something like $E \approx 27.642 \times mc^2$?  Why is time dilation describable by something as neat as $t' = \sqrt{\frac{t}{1 - \frac{v^2}{c^2}}}$ and not something ugly like $t' \approx 672.097 \times 10^{-4} \times \sqrt{\frac{t}{1 - \frac{v^2}{c^2}}}$.  ... and so forth.    I'm not well educated on matters of physics and so I feel a bit sheepish asking this.   Likewise I'm not sure if this is a more philosophical question or one that permits a concrete answer ... or perhaps even the premise of the question itself is flawed ... so I would gratefully consider anything that sheds light on the nature of the question itself as an answer.    EDIT: I just wished to give a little more context as to where I was coming from with this question based on some of the responses:  @Jerry Schirmer comments:      You do have an ugly factor of $2.997458 \times 10^8 m/s$ in front of everything. You just hide the ugliness by calling this number c.   These are not the types of "ugly constants" I'm talking about in that this number is the speed of light. It is not just some constant needed to balance two side of an equation.  @Carl Witthoft answers:      It's all in how you define the units ...   Of course this is true, we could in theory hide all sorts of ugly constants by using different units on the right and the left. But as in the case of $E=mc^2$, I am talking about equations where the units on the left are consistent with the units on the right, irrespective of the units used. As I mentioned on a comment there:     $E=mc^2$  could be defined using units like $m$ in imperial stones ($\textsf{S}$), $c$ in cubits/fortnight ($\textsf{CF}^{−1}$) and $E$ in ... umm ... $\textsf{SC}^2\textsf{F}^{−2}$ ... so long as the units are in the same system, we still don't need a fudge factor.   When the units are consistent in this manner, there's no room for hiding fudge constants. I've got a stylesheet that will not, for whatever reason, apply list-style-type to a UL element. I'm using YUI's Grid CSS with their reset-fonts-grid.css file, which I know strips that out as part of the CSS reset.  After calling YUI, I call the stylesheet for the website and in there have a block for UL:  ul {list-style-type: disc;}   I've also tried setting it via list-style but get the same result. I know that the above CSS block is getting read as if I add things like padding or margins those do get applied. The style-type isn't showing up in either Firefox or IE.  The only other CSS I've applied to UL's are in a #nav div but that CSS doesn't touch the list-style-type, it uses the reset that YUI provided, and YUI and the site style sheet are the only two CSS sheets that are called.  I've also got FCKEditor on the admin side of the site and that editor does show the bullet styles so I know it has to be something with the CSS that isn't being filtered by FCKEditor.