lines

I'd like to draw lines on an image. Basically allow the user to draw a path for mountain trails they like. 1) Does anyone know a good simple library for drawing basic lines? 2) After a user draws a bunch of lines on an image, what would be the best way to save the data to the database? Drawing lines Paper.js . Look at the Path Simplification example. Raphaël - Raphael SketchPad You can easily overlay the elements on top of an image so the user draws on the image. Also, just for fun, but have you seen SVG-edit ( demo )? Saving the line data The SketchPad script above provided drawn data in JSON

I'm trying to delete the first two lines of a file by just not printing it to another file. I'm not looking for something fancy. Here's my (failed) attempt at awk: awk '{ (NR > 2) {print} }' myfile That throws out the following error: awk: { NR > 2 {print} } awk: ^ syntax error Example: contents of 'myfile': blah blahsdfsj 1 2 3 4 What I want the result to be: 1 2 3 4 Use tail: tail -n+3 file from the man page: -n, --lines=K output the last K lines, instead of the last 10; or use -n +K to output lines starting with the Kth How about: tail +3 file OR awk 'NR>2' file OR sed '1,2d' file You're

So I have a file1.txt with a list of names, and a file2.txt with another list of names and I need a list with the names that are in both files. I tried grep-f file1.txt file2.txt > newlist.txt but for some reason it isn't working, and the newlist.txt has names that are not in file1. Does anyone know why this is happening and what i could do to get only the names that are on both lists? thank you. If file1.txt and file2.txt are sorted, you could use 'comm' comm -12 file1.txt file2.txt > newlist.txt If each the names in each list are unique, then you can find their intersection as follows: sort

I would like to read a content String from file lne by line, and in each line remove all caharcters that are not one of the following [ { } ] I wanted to used a method: line = line.replaceAll("[^[({})]]",""); but the problem is that char [ and ] means in regex syntax something else. How to deal with it? Best regards In Java, the regex character classes can have unions and intersections, thus, [ and ] must be escaped inside if you want them to be treated as literal symbols. And since \ can be used to define escape sequences, it should be doubled to denote a literal regex-escaping \ . Use line =