prefix

问题 So i want to match all strings of the form with a regex (word1|word2|word3)/some/more/text/..unlimited parts.../more so it starts with specific word and it does not end with / examples to match: word1/ok/ready word2/hello word3/ok/ok/ok/ready What i want in the end is when i have a text with above 3 examples in it (spread around in a random text), that i receive an array with those 3 matches after doing regex.exec(text); Anybody an idea how to start? Thanks! 回答1: Something like this should

来源： https://stackoverflow.com/questions/60853582/why-how-does-the-longest-proper-prefix-suffix-algorithm-work

来源： https://stackoverflow.com/questions/24055308/add-a-prefix-to-all-rows-in-r

来源： https://stackoverflow.com/questions/24055308/add-a-prefix-to-all-rows-in-r

问题 I want a ‘+’ Sign in the Textfield which cannot be erased. A user should be able to enter values after it and if he presses backspace it should only erase the value he entered. And when I write any other number it will automatically add a ‘+’ at the beginning of the enter value. For Example:- I want to add country code in the textfield so, '+' automatically add in the beginning of the field as soon as user start typing a country code. 回答1: normally you should post your coding tries here,

问题 I want a ‘+’ Sign in the Textfield which cannot be erased. A user should be able to enter values after it and if he presses backspace it should only erase the value he entered. And when I write any other number it will automatically add a ‘+’ at the beginning of the enter value. For Example:- I want to add country code in the textfield so, '+' automatically add in the beginning of the field as soon as user start typing a country code. 回答1: normally you should post your coding tries here,

问题 Alright, I've been programming in Java for the better part of three years, now, and consider myself very experienced. However, while looking over the Java SE source code, I ran into something I didn't expect: in class Double : public static final double MIN_NORMAL = 0x1.0p-1022; // 2.2250738585072014E-308 public static final double MIN_VALUE = 0x0.0000000000001P-1022; // 4.9e-324 I did not expect this and can't find out what it means. If you don't know, I'm referring to the p and P that are

问题 I have a schema with following attributes in schema element: <schema xmlns="http://www.w3.org/2001/XMLSchema" xmlns:abc="http://abc.example.com" targetNamespace="http://abc.example.com" elementFormDefault="qualified" attributeFormDefault="unqualified"> I could compile it and get java classes. Using these classes, I filled in data in an object and marshalled it to get an XML file. But the XML elements in this marshalled file is not having the prefix "abc". I tweaked a little using

问题 I have a schema with following attributes in schema element: <schema xmlns="http://www.w3.org/2001/XMLSchema" xmlns:abc="http://abc.example.com" targetNamespace="http://abc.example.com" elementFormDefault="qualified" attributeFormDefault="unqualified"> I could compile it and get java classes. Using these classes, I filled in data in an object and marshalled it to get an XML file. But the XML elements in this marshalled file is not having the prefix "abc". I tweaked a little using

问题 I would have a column where the data looks like this: M999-00001 M999-00002 ... Is there a way to remove all the 'M's in the column in R? 回答1: We can use sub df1[,1] <- sub("^.", "", df1[,1]) Or use substring substring(df1[,1],2) data df1 <- data.frame(Col1 = c("M999-00001", "M999-0000"), stringsAsFactors=FALSE) 回答2: You can use gsub function for the same Col1 <- gsub("[A-z]","",Col1) [1] "999-00001" "999-0000" data Col1 = c("M999-00001", "M999-0000") 回答3: df %>% transform(col_name=str