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Can I color text by using an image, so that the color isn't flat? I'm using tikz to attempt to make a book cover, and I have a "wallpaper" image that looks like leather (not that I've handled that many leather-bound books). I'm using the node command to place text over the top of it, but none of the colors I've experimented with look decent.  Can I use an image of gold-leaf as the fill/stroke for the text? Or for that matter, for the path lines as well?  I've tried googling for this, but I can't figure out a set of keywords non-generic enough to pull back useful results. What is the difference between “Size” and “Size on disk?” Looking at the properties for a Windows file I get two attributes, “Size” and “Size on disk,”  and "Size on disk" is always larger.  What do these two metrics mean? If you view the Earth from far enough away can you observe its past? I have a shell script with this code:  var=`hg st -R "$path"` if [ -n "$var" ]; then     echo $var fi   But the conditional code always executes, because hg st always prints at least one newline character.   Is there a simple way to strip whitespace from $var (like trim() in )?   or   Is there a standard way of dealing with this issue?   I could use  or , but I'd like to think there is a more elegant solution to this problem. Looking for the proof of the lemma asserting that the conical surface (envelope) is a closed space. Thank you. I wish to open a pdf in photoshop , remove some content and then resave it.  When i do this the new pdf has trimmed margins. What is the best approach to keep the margins the save as the original file. I appreciate indesign or other software would be a better for this job Smoothing/interpolating across images in an ImageCollection to remove missing data I have some code that is working properly to calculate the monthly NDVI averages for the previous two years from a date but I sometimes have missing data in some of the months and I would like to get an average based on the mean of the previous two months. I suppose I could also interpolate from the closest geographic data point but it seems like it would be better to interpolate across time than distance given that sometimes the clouds cover reasonably large areas.   But I'm certainly open to other opinions, I just want to fill these holes as accurately as possible. Is there an efficient way to do this.  and here is the code itself:  // pick a landsat tile footprint to use as my geometry var wrs2_descending = ee.FeatureCollection('ft:1_RZgjlcqixp-L9hyS6NYGqLaKOlnhSC35AB5M5Ll'); // use a manually defined point to pick the WRS2 tile var wrs2_filtered = wrs2_descending.filterBounds(roi); var layer1 = ui.Map.Layer(wrs2_filtered, {}, 'WRS2 filtered'); Map.layers().set(1, layer1);  var imageCollection = ee.ImageCollection('LANDSAT/LC08/C01/T1_SR').filterBounds(wrs2_filtered); var monthCount = ee.List.sequence(0, 11);  // Function to cloud mask from the pixel_qa band of Landsat 8 SR data. function maskL8sr(image) {   // Bits 3 and 5 are cloud shadow and cloud, respectively.   var cloudShadowBitMask = 1 &lt;&lt; 3;   var cloudsBitMask = 1 &lt;&lt; 5;    // Get the pixel QA band.   var qa = image.select('pixel_qa');    // Both flags should be set to zero, indicating clear conditions.   var mask = qa.bitwiseAnd(cloudShadowBitMask).eq(0)       .and(qa.bitwiseAnd(cloudsBitMask).eq(0));    // Return the masked image, scaled to reflectance, without the QA bands.   return image.updateMask(mask).divide(10000)       .select("B[0-9]*")       .copyProperties(image, ["system:time_start"]); }  // run through the image collection and generate monthly NDVI median images var composites = ee.ImageCollection.fromImages(monthCount.map(function(m) {   var startMonth = 1; // thinking that I should always start from Jan so the series are similar   var startYear = ee.Number(2017-1); // number is one year before the current one    var month = ee.Date.fromYMD(startYear, startMonth, 1).advance(m,'month').get('month');   var year = ee.Date.fromYMD(startYear, startMonth, 1).advance(m,'month').get('year')    // filter by year and then filter by month to get monthly mosaics   var filtered = imageCollection.filter(ee.Filter.calendarRange({     start: year.subtract(1), // we want an average of the last two years     end: year,     field: 'year'   })).filter(ee.Filter.calendarRange({     start: month,     field: 'month'   }));   // mask for clouds and then take the median   var composite = filtered.map(maskL8sr).median();   return composite.normalizedDifference(['B5', 'B4']).rename('NDVI')       .set('month', ee.Date.fromYMD(startYear, startMonth, 1).advance(m,'month')); })); print(composites);  Map.addLayer(composites, {min: 0, max: 1}, 'check');  // stack the ImageCollection into a multi-band raster for downloading var stackCollection = function(collection) {   // Create an initial image.   var first = ee.Image(collection.first()).select([]);    // Write a function that appends a band to an image.   var appendBands = function(image, previous) {     return ee.Image(previous).addBands(image);   };   return ee.Image(collection.iterate(appendBands, first)); }; var stacked = stackCollection(composites); print('stacked image', stacked);  // Display the first band of the stacked image. Map.addLayer(stacked.select(0).clip(wrs2_filtered), {min:0, max:1}, 'stacked'); So the stories of the Hunger Games are set in , a post-apocalyptic society situated in North America. Is there anything to explain what caused the Apocalypse? Whether from the main books, any extra material or interviews? (No fanfic please.)  As well as the cause, is there any indication of when the apocalypse happened? And how long after the apocalypse are the events of the Hunger Games? Let $(e_n)$ (where $ e_n $ has a 1 in the $n$-th place and zeros otherwise) be unit  standard vectors of $\ell_\infty$.   Why is $(e_n)$ not a basis for $\ell_\infty$?  Thanks. Which homology groups of a closed orientable 6-manifold can be isomorphic to $\mathbb{Z}^3$? List all $i$ for which there is a closed orientable $6$-manifold $M$ with $H_i(M) =\mathbb{Z}\oplus\mathbb{Z}\oplus\mathbb{Z}$.   I am working on an old exam problem and this one stumped me. Progress so far:  I can take $Y=\mathbb{T}^3 \times \mathbb{S}^3$ and get the desired group for $i =1,5,2,4$ I think. But this construction I believe gives $H_3(Y)=\mathbb{Z}^2$. What to do in this case? prove that $\mathbb{Q}^n$is dense subset of $\mathbb{R^n}$ How to get the current time in Python How can I manually generate a random number from a given distribution, as for instance, 10 realisations from the standard normal distribution? After S.H.I.E.L.D confiscates Jane's work in Thor, the researchers discuss what they'll do next.  Erik mentions two colleagues. The first is reasonably implied to be Bruce Banner, but who is the second colleague he mentions? Transcribed from the film:  Jane Who are these people? Erik I knew this scientist... a pioneer in gamma radiation. S.H.I.E.L.D showed up and... umm. He wasn't heard from again. Jane They're not going to do that to us. I'm going to get everything back. Erik mumbles Please. Let me contact one of my colleagues. He's had some dealings with these people before. I'll email him and maybe he can help. Darcy They took your laptop, too. What does this notification icon mean? Samsung s7 Color of questions with accepted answers on user profile page Related to these questions:    When viewing the Meta user profile, the difference between questions with accepted answers and questions without is pretty subtle. At first glance, I couldn't tell the difference at all. Can the contrast between the styles be increased a bit to make it easier to see?     This screenshot doesn't look too bad, but when looking at a list going down a whole page, it gets a bit difficult to pick one out at a glance. (I'm guessing even more so for some of the color-challenged users) Has it been practically proven that quantum superposition exists ? If yes, how does it even work? When i tried to install PIP for python3 in Ubuntu 18.04.2 LTS  Command I used:   root@DESKTOP-0BEE3OD:/mnt/c# apt install python3-pip  E: Could not read response to hello message from hook [ ! -f /usr/bin/snap ] || /usr/bin/snap advise-snap --from-apt 2&gt;/dev/null || true: Success   I am not able to fix this error. Should you use "who" or "that" when talking about multiple people doing something? Which of the following is correct?        There were 10 people that went to the store.   There were 10 people who went to the store.      Edit:  Which of the following is correct?        There were 10 people that had brown hair.   There were 10 people who had brown hair. I am looking for tutorials, articles or books containing theory of  in context of mathematical physics. Please suggest.