expression

问题 i'm doing something like excel, i have something like this: 1 2 3 A1 B1 C1 where it replaces the content for specified content, where A1 replaces the content for 1. B1 replaces the content of 2...and etc... i'm using a multidimensional array, and i do the things like this: int offset = 0, readCharCount; while(sscanf(matris[i][c] + offset, "%c%d%*c%n", &col, &linha, &readCharCount) == 2){ //printf("%c, %d\n", col, linha); //strcpy(matris[i][c], matris[linha-1][col - 'A']); offset +=

问题 I am trying to create the following dynamically, however I am having problems calling the extension method FirstOrDefault : using(var context = new Entities()) { var list = context.Engines.Include("Cars").Select(e => e.Cars.FirstOrDefault()).ToList(); } I have the following Expression parameter = Expression.Parameter(typeof(Engine), "e"); Expression property = Expression.Property(parameter, "Cars"); parameter = {e} property = {e.Cars} Those are good, but I am encountering a problem when I try

问题 I'm looking for regex to extract json string from text. I have the text below, which contains JSON string(mTitle, mPoster, mYear, mDate) like that: {"999999999":"138138138","020202020202":{"846":{"mTitle":"\u0430","mPoster":{" small":"\/upload\/ms\/b_248.jpg","middle":"600.jpg","big":"400.jpg"},"mYear" :"2013","mDate":"2014-01-01"},"847":{"mTitle":"\u043a","mPoster":"small":"\/upload\/ms\/241.jpg","middle":"600.jpg","big":" 138.jpg"},"mYear":"2013","mDate":"2013-12-26"},"848":{"mTitle":"

问题 In pdb (or ipdb) we can execute statements and evaluate expressions with the ! or p commands: p expression Evaluate the expression in the current context and print its value. [!]statement Execute the (one-line) statement in the context of the current stack frame. The exclamation point can be omitted unless the first word of the statement resembles a debugger command. To set a global variable, you can prefix the assignment command with a global command on the same line So, for example, I can

问题 I have read many postings on this topic using expression() , paste() , and bquote() , or some combination. I think I am close to solving my problem, but I just can't get there. The following script generates a plot labelled with "y = 1 + 2(x); r^2= 0.9". How can I italicize "y" and "x", and italicize the "r" and superscript the 2 of "r^2"? If I have overlooked a relevant earlier post, sorry, but please direct me to it. df <- data.frame(x=c(1:5), y=c(1:5)) a <- 1 b <- 2 r2 <- 0.9 eq <- paste(

问题 I have read many postings on this topic using expression() , paste() , and bquote() , or some combination. I think I am close to solving my problem, but I just can't get there. The following script generates a plot labelled with "y = 1 + 2(x); r^2= 0.9". How can I italicize "y" and "x", and italicize the "r" and superscript the 2 of "r^2"? If I have overlooked a relevant earlier post, sorry, but please direct me to it. df <- data.frame(x=c(1:5), y=c(1:5)) a <- 1 b <- 2 r2 <- 0.9 eq <- paste(

问题 Below, I have R code that plots a grouped bar plot. group_name = c('A_1x', 'A_1x', 'A_2x', 'A_2x', 'A_3x', 'A_3x', 'A_4x', 'A_4x') mydata2 <- data.frame(mygroup = group_name, mysubgroup = factor(c("Yes", "No"), levels = c("Yes", "No")), value = c(60,40,90,10,55,45,88,12)) ggplot(mydata2, aes(mygroup, value, fill = mysubgroup)) + geom_bar(position = "dodge", width = 0.5, stat = "identity")+ coord_flip() Currently, the plot looks like below. However, I want to show expressions in the x axis as

问题 In F#, how can I create a custom attribute to apply on expressions? I looked for resources everywhere, but I didn't find nothing. For exemple The attribute [<Entrypoint>] can be applied to some expression, and by consequence the compiler can infer that expression should be of type array string -> int . How can I create a custom attribute to work simillary ? 回答1: To create a custom attribute, simply declare a class that inherits from System.Attribute : type MyAttribute() = inherit System

问题 In F#, how can I create a custom attribute to apply on expressions? I looked for resources everywhere, but I didn't find nothing. For exemple The attribute [<Entrypoint>] can be applied to some expression, and by consequence the compiler can infer that expression should be of type array string -> int . How can I create a custom attribute to work simillary ? 回答1: To create a custom attribute, simply declare a class that inherits from System.Attribute : type MyAttribute() = inherit System

问题 This question already has answers here : Closed 9 years ago . Possible Duplicate: Is there a string math evaluator in .NET? Can C# parse mathematical expressions such as y=3*x + 3 into string? If so, ho? I appreciate your help. 回答1: Here's a bit of code I wrote a while ago to parse infix (operator operand operator) equations. There are some small classes and helper functions missing, but it should be fairly easy to implement them. If you need them or any help with it, let me know and I can