What are methods of Object Class in Python?
Finding what methods a Python object has
In terms of UX what do you guys think is the best approach when integrating a trial period for subscriptions?  My application offers a 15 day trial, at the minute the user can sign up without providing any payment information (Paypal Subscription). The account is then set to trial status and after 15 days the user will be redirected to an upgrade page.  Do you think this is the best approach? I am unsure whether or not to let Paypal manage the trial, this however means that the user will need to go through the Paypal payment system during signup. I think this may put some people off signing up.  On the other hand this approach may increase the number of conversions to a full account. How to view network traffic requested by a specific app? There are lots of discussion on how to see which app is requesting network connection. I have tried the following apps:  tcapturepacket wifi monitor connection tracker   However, none of them was useful. For example, for a short period of time, I uploaded a 30KB pcap file which can be viewed . Still I haven't find out which app is requesting connection and to where it is trying to connect.  I also tried to look at adb logcat, but didn't find useful information. Maybe something has been missed here. Any guess? Meaning of U suffix Maximum total distance between points on a sphere What is the configuration (set of locations) of $n$ points on the surface of a sphere such that the sum of distances is maximum for $n=1,2,3,...$?  The sum of distances is measured by summing the lengths of every straight line (through the sphere) connecting every possible combination of $2$ points.  All the points are on a single sphere of radius $R$.  Here's a visualization:   Acknowledgements: Based on  Physics S.E. question. Image from . Finding the limit $ \lim_{x\to a^+} \frac{\cos(x)\ln(x-a)}{\ln(e^x-e^a)} $ Panasonic Eneloop BK-3MCC (4th gen) - where I can find maximum discharge current? Im looking for some official information source about maximum current for Panasonic Eneloop BK-3MCC rechargeable batteries.  All I found is , there is just 1 table (nothing about maximum discharge current), charge and discharge characteristics.  UPDATE LINK:   / edited - I fixed my mistake, I meant 6A not 8A /  There is discharge characteristic for 6000mA discharge. So... I can safely draw 6A from that AA cell? Why is $\frac{d^n}{dx^n}(y(x))$ the notation for the $n$th derivative of $y(x)$, instead of $\frac{d^n}{d^nx}(y(x))$? I've always wondered why the numerator is $d^n$ while the denominator is $dx^n$ instead of $d^nx$ like the numerator.  I must be missing something very obvious or fundamental. Is this notation derived from the chain rule in some way? Merge two custom post types into one admin page? I am building a site with 4 custom post types. To make things easier for our client/admin, I'm wondering if there is a way to merge those custom post types into one list in the backend? Like if you look at normal backend admin page with the list and columns of posts, can a page like that pull in 3 other post types for easy sorting/searching?  I can't combine the CPTs into one, they must remain seperate outside of one 'viewing' page in the admin area if possible.  Any thoughts on how to do this?? Or even where to start looking/thinkging of how to develop this? I have just installed Ubuntu 16.04 32-bit.   When I opened its software store, I found that it's not showing the apps I installed in Ubuntu 15.10 like Clementine, Gdebi package installer or synaptic package manager, dconf, acetoneiso etc.   I need these applications. How can I install them? Why is the sky never green? It can be blue or orange, and green is in between! I, like everybody I suppose, have read the  why the colour of the sky is blue:     ... the two most common types of matter present in the atmosphere are   gaseous nitrogen and oxygen. These particles are most effective in   scattering the higher frequency and shorter wavelength portions of the   visible light spectrum. This scattering process involves the   absorption of a light wave by an atom followed by reemission of a   light wave in a variety of directions. The amount of multidirectional   scattering that occurs is dependent upon the frequency of the light.   ... So as white light.. from the sun passes through our atmosphere,   the high frequencies become scattered by atmospheric particles while   the lower frequencies are most likely to pass through the atmosphere   without a significant alteration in their direction. This scattering   of the higher frequencies of light illuminates the skies with light on   the BIV end of the visible spectrum. Compared to blue light, violet   light is most easily scattered by atmospheric particles. However, our   eyes are more sensitive to light with blue frequencies. Thus, we view   the skies as being blue in color.   and why sunsets are red:     ... the light that is not scattered is able to pass through our   atmosphere and reach our eyes in a rather non-interrupted path. The   lower frequencies of sunlight (ROY) tend to reach our eyes as we sight   directly at the sun during midday. While sunlight consists of the   entire range of frequencies of visible light, not all frequencies are   equally intense. In fact, sunlight tends to be most rich with yellow   light frequencies. For these reasons, the sun appears yellow during   midday due to the direct passage of dominant amounts of yellow   frequencies through our atmosphere and to our eyes.      The appearance of the sun changes with the time of day. While it may   be yellow during midday, it is often found to gradually turn color as   it approaches sunset. This can be explained by light scattering. As   the sun approaches the horizon line, sunlight must traverse a greater   distance through our atmosphere; this is demonstrated in the diagram   below. As the path that sunlight takes through our atmosphere   increases in length, ROYGBIV encounters more and more atmospheric   particles. This results in the scattering of greater and greater   amounts of yellow light. During sunset hours, the light passing   through our atmosphere to our eyes tends to be most concentrated with   red and orange frequencies of light. For this reason, the sunsets have   a reddish-orange hue. The effect of a red sunset becomes more   pronounced if the atmosphere contains more and more particles.   Can you explain why the colour of the sky passes from blue to orange/red skipping altogether the whole range of green frequencies?  I have only heard of the legendary 'green, emerald line/ flash'     that appears in particular circumstances     Green flashes are enhanced by mirage, which increase refraction... is more likely to be seen in stable, clear air,... One might expect to see a blue flash, since blue light is   refracted most of all, and ... is   therefore the very last to disappear below the horizon, but the blue   is preferentially scattered out of the line of sight, and the   remaining light ends up appearing green   but I have never seen it, nor do I know anybody who ever did. How to pass the output of one command as the command-line argument to another? So I have a script that, when I give it two addresses, will search two HTML links:  echo "http://maps.google.be/maps?saddr\=$1\&amp;daddr\=$2" | sed 's/ /%/g'   I want to send this to wget and then save the output in a file called temp.html. I tried this, but it doesn't work. Can someone explain why and/or give me a solution please?  #!/bin/bash url = echo "http://maps.google.be/maps?saddr\=$1\&amp;daddr\=$2" |  sed 's/ /%/g' wget $url How could the human race be saved in Interstellar? In  (2014) the human race seemed to be facing pretty poor odds until they discovered a convenient wormhole placed by an unknown entity expressed as "they". Later in the movie, we discover that       "they" are actually the human race in the future, reaching back in  time to save itself.   The end of the movie gets a little wild on the physics end, and I'm happy to take that ending as is - no need for it to make sense - but one very basic detail does bother me:  How could the human race have gone back in time to save itself from circumstances that would have caused us to go extinct without our own help (the convenient wormhole)? I am wondering how to differentiate all these different joins ... What is the difference between local and global sequence alignments? There are a bunch of , and I don't want to get bogged down in the maths behind them as this not only between software but varies from software version to version.  There are two main divides in the programs; some use local alignments and others use global alignments. My question is threefold:   What are the fundamental differences between the two? What are the advantages and disadvantages of each? When should one use either a global or local sequence alignment? Find out trace of a given matrix $A$ with entries from $\mathbb{Z}_{227}$ Let $A$ be a $227\times 227$ matrix with entries in $\mathbb{Z}_{227}$ such that all of its eigen values are distinct. What would be its trace? I think it is zero by adding all 227 elements but i am not sure.  Edited: Here I have assumed that eigenvalues are in a base field. In a dictionary like this:  Dictionary&lt;string, string&gt; openWith = new Dictionary&lt;string, string&gt;();  openWith.Add("txt", "notepad.exe"); openWith.Add("bmp", "paint.exe"); openWith.Add("dib", "paint.exe"); openWith.Add("rtf", "wordpad.exe");  Console.WriteLine("For key = \"rtf\", value = {0}.", openWith["rtf"]);   The output is:     For Key = "rtf" value = wordpad.exe   What does the {0} mean? Analytic continuation of a power series 2 Another Qual question here,  For the function $$\sum_{n=0}^\infty z^{2^n}$$,  Prove the following:  i) $f$ converges to a function analytic in the open unit disk $D$,  ii) $f(z) =z+f(z^2)$ and  iii) $f(z)$ can not be analytically continued past any point on the unit circle.  I can even see (ii) very easily, but I can not see how can I prove rigorously (i) and  (iii). Help please. zsh scripting - How do I NOT match a pattern in filename generation? I'm currently trying to loop through a set of directories, but only the ones I care about.   $ ls -d */ cfdpost_statefiles/     p050L0260/  p050L0510/  p060L0390/  p070L0260/  p070L0510/  p092L0390/  p097L0260/  p110L0390/  p131L0325/  p150L0510/  profiles/ ERCOFTAC_TestSettings/  p050L0390/  p060L0260/  p060L0510/  p070L0390/  p084L0510/  p094L0325/  p100L0510/  p125L0510/  p136L0260/  p162L0260/  settings/   I want to match all the p###* directories except for the ones beginning with p125 and p150.  If I just do patterns with a pipe, I get:  $ for dir in ./p(125|150)*(/); echo $dir ./p125L0510 ./p150L0510   However, if I try and use the ^ like it shows :  $ for dir in ./p^(125|150)*(/); echo $dir zsh: no matches found: ./p^(125|150)*(/)   Any ideas how to proceed? How do I find the location of Python module sources? How do I learn where the source file for a given Python module is installed? Is the method different on Windows than on Linux?  I'm trying to look for the source of the datetime module in particular, but I'm interested in a more general answer as well. I recently tried to use QGIS and I wondered if you can convert a draft ArcGIS map (*.mxd file) into a QGIS project (*.qgs file).   This would avoid thematize the entire project.