Friend $A$ claims that he has eaten $1$ apple today.  Friend $B$ responds. Congrats, I have eaten $0$ apples, so that is $\infty$ more apples than me.  Friend $C$ says, but I have also eaten $0$ apples. So how many times more than you have I done? $0$ or $\infty$?
If I have $10$ apples, but you have $5$ apples, then I have $2$ times more apples than you. But what if I have $10$ apples, but you don't have any apples?   If you look at the graph $f(x)=\frac{10}{x}$, it shows that when $x$ approaches $0$, $f(x)$ approaches infinity. So it means I have infinity times more apples than you?
Why do I get TypeError: can't multiply sequence by non-int of type 'float'? I am typing to get a sale amount (by input) to be multiplied by a defined sales tax (0.08) and then have it print the total amount (sales tax times sale amount).  I run into this error. Anyone know what could be wrong or have any suggestions?   salesAmount = raw_input (["Insert sale amount here \n"]) ['Insert sale amount here \n']20.99 &gt;&gt;&gt; salesTax = 0.08 &gt;&gt;&gt; totalAmount = salesAmount * salesTax  Traceback (most recent call last):   File "&lt;pyshell#57&gt;", line 1, in &lt;module&gt;     totalAmount = salesAmount * salesTax TypeError: can't multiply sequence by non-int of type 'float' Why every map $f : S^n \to T^n (n>1)$ has topological degree zero? Why every map $f : S^n \to T^n (n&gt;1)$ has topological degree zero?  I don't know anything about covering spaces, and has been told to me that this assertion comes from this theory!  I do appreciate any help. Removing intercept from GLM for multiple factorial predictors only works for first factor in model I am running a binomial logistic regression with a logit link function in R. My response is factorial [0/1] and I have two multilevel factorial predictors - let's call them $a$ and $b$ where $a$ has 4 factor levels  $(a_1,a_2,a_3,a_4)$ and $b$ has 9 factor levels $(b_1,b_2,\dotsc,b_9)$. Therefore:  mod &lt;- glm(y ~ a + b, family = binomial(logit), data=pretend) summary(mod)   The model output would then show all the information about the model as well as the coefficients.  There is a factor level for both a and b missing (a1 and b1) from the summary output. I understand that it is constrained in the "intercept" of the model. I have read that if I want to remove the intercept term and see the estimates for those factor levels I can just add -1 to the model formula, i.e.:  mod2 &lt;- glm(y ~ a + b - 1, family=binomial(logit), data=pretend) summary(mod2)   In the new model (mod2) the intercept term is then gone and variable a's factor-level a1 is given amongst the list of coefficients. But, variable b's factor-level b1 is still missing and given that there is no intercept term anymore, how can I interpret the odds-ratio for that factor level then?  Could someone please explain to me how to get the coefficient for b1 too and why this is happening? For what powers $k$ is the polynomial $n^k-1$ divisible by $(n-1)^2$? For some reason I can't unhide my objects anymore in this file. Is it a bug? Should I disable google maps scroll wheel zoom? In most applications of google maps the scroll wheel will zoom the map instead of scrolling it.  Personally I find this confusing, and after years of using google maps, both on the google maps web site and embedded google maps, I still often make the mistake of trying to scroll the map with scroll wheel and end up zooming it instead.  The google maps API allows me to disable scrollwheel zoom when I embed a map in my page.  The question is should I disable it?  On the one hand scroll wheel zoom is unconventional in the context of the web as a whole - in the vast majority of cases the scroll wheel scrolls things.  On the other hand scroll wheel zoom is established convention for maps.  It definitely would be a better experience for me if scroll wheel zooming was disabled, but what about the web browsing population in general?  I did some searching on whether I should disable scroll zoom and couldn't find any guidelines. So, to scroll zoom or not to scroll zoom? Does the mass of a battery change when charged/discharged? If so, how much? Is it possible to detect it, or is it beyond any measurement?  I'd say there are two possible scenarios (depending on the battery type) and both seem interesting:   The battery reacts chemically with its environment. The battery doesn't exchange any matter with its environment except electrons. I suppose there should be some difference at least due to the principle of energy-matter equivalence, but the difference is most likely immeasurable. What happens to Red Skull after Thanos gets the Soul Stone? Is a sub-shell the same thing as a child-shell There are this two names: a subshell and a child-shell.  Yes, a child process will be started by any of this:  sh -c 'echo "Hello"' ( echo "hello" ) echo "$(echo "hello") echo "hello" | cat   Are all equivalent and share the same name? Do all share the same properties?    POSIX :     A shell execution environment consists of ....   But the last paragraph of above link has this:     A subshell environment shall be created as a duplicate of the shell environment, except that signal traps that are not being ignored shall be set to the default action.    And specially:     Command substitution, commands that are grouped with parentheses, and asynchronous lists shall be executed in a subshell environment. Additionally, each command of a multi-command pipeline is in a subshell environment; ....   The sh -c 'echo "Hello"' is not included there, should that be called a subshell also? Order of products of elements in a finite Abelian group Call C++ library in C# I have a lot of libraries written in C++. I want to call these libraries from C#, however, I have met many problems. I want to know if there is a book or guideline to tell me how to do that. Is it bad to use a pacifier? I've been using it when she gets fussy and she seems to love it. Is this a bad habit to get into? I've heard there are potential dental/breastfeeding/dependency issues. Is there any truth to this? How can Star Trek: Countdown ever be considered canon? I am flying to Tbilisi, Georgia with Turkish Airline. My stay in Istanbul is 12 hours. Can I get transit visa to visit Istanbul city ?    I am from Pakistan with Oman employment visa. How does a circular lens produce rectangular shots? Mouseover tooltip for delete count is wrong How to use st_buffer? I would like to calculate a buffer of 5km around country polygons. However, I somehow always get a warning and an error. Here is a reproducible example code.   library(sp) library(sf) library(tmap)  library(rnaturalearth) countries_sp &lt;- ne_countries(scale = 10)  countries_sp &lt;- countries_sp[(countries_sp@data$geounit %in% "France"), ]  proj4string(countries_sp) &lt;- CRS("+init=epsg:4326")   countries_for_buff &lt;- st_as_sf(countries_sp, crs ="+proj=laea +lat_0=52 +lon_0=10 +x_0=4321000 +y_0=3210000 +ellps=GRS80 +units=m +no_defs ")  countries_buff_5km &lt;- st_buffer( countries_for_buff, 5000)   here the warning:  dist is assumed to be in decimal degrees (arc_degrees). Warning message: In st_buffer.sfc(st_geometry(x), dist, nQuadSegs, endCapStyle = endCapStyle,  : st_buffer does not correctly buffer longitude/latitude data   Then   tm_shape(countries_sp) +   tm_polygons() + tm_shape(countries_buff_5km) +   tm_polygons()   gives the error   Error in if (all(tiny) &amp;&amp; show.messages) warning("all relative area sizes are below thres.poly",  :     missing value where TRUE/FALSE needed   What am I doing wrong? I guess there is something about the projection that does not quite work out the way it should. I am trying to pass a variable into jq like this '.Linux.date.$var' so far I have tried quoting them by name which is working fine. But I want to use variable to call them.  I have this, which is working fine  exectime=$(date -d now);     cp $check_exec_history $check_exec_history.tmp     jq --arg key1 true --arg key2 "$exectime" --arg name "$name" '.Linux.script_executed.first = $key1 | .Linux.date_executed.first = $key2' $check_exec_history.tmp &gt; $check_exec_history;      rm $check_exec_history.tmp;   I want to get to this, but not working:  name=first; exectime=$(date -d now); cp $check_exec_history $check_exec_history.tmp jq --arg key1 true --arg key2 "$exectime" --arg name "$name" ".Linux.script_executed.$name = $key1 | .Linux.date_executed.$name = $key2" $check_exec_history.tmp &gt; $check_exec_history;  rm $check_exec_history.tmp;   I came this far: using this answer  But I am not sure where I am doing mistake.  name=first; exectime=$(date -d now);     cp $check_exec_history $check_exec_history.tmp     jq --arg key1 true --arg key2 "$exectime" --arg name "$name" '.Linux.script_executed.name==$name = $key1 | .Linux.date_executed.name==$name = $key2' $check_exec_history.tmp &gt; $check_exec_history; rm $check_exec_history.tmp; How do I ping a website or IP address with Python? How to change kernel at boot I installed the latest kernel (4.1) and want to boot into it instead of 3.9. How can i do this on ubuntu 15.04?