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Articles on Trending Technologies
Technical articles with clear explanations and examples
Panic! Macro in Rust Programming
Handling critical errors in Rust is done with the help of panic! Macro. There are other ways to handle errors in Rust, but panic is unique in the sense that it is used to deal with unrecoverable errors.When we execute the panic! Macro, the whole program unwinds from the stack, and hence, it quits. Because of this manner with which the program quits, we commonly use panic! for unrecoverable errors.SyntaxThe syntax of calling a panic looks like this −panic!("An error was encountered");We usually pass a custom message inside the parentheses.ExampleConsider the code shown below as a reference −fn drink(beverage: &str) ...
Read MoreHow to combine a data frame and a named vector if name matches with a column in R?
If we have a data frame that contains a character column and a named vector which has the same names as in the character column of the data frame then we can combine this data frame and the vector by using match function be appropriately defining the names and the character column. Check out the below example to understand how it can be done.ExampleConsider the below data frame df1 and the vector v1 −df1
Read MorePath Struct in Rust Programming
Path struct in Rust is used to represent the file paths in the underlying filesystem. It should also be noted that a Path in Rust is not represented as a UTF-8 string; instead, it is stored as a vector of bytes (Vec).ExampleConsider the example shown below −use std::path::Path; fn main() { // Create a `Path` from an `&'static str` let path = Path::new("."); // The `display` method returns a `Show`able structure let display = path.display(); // Check if the path exists if path.exists() { println!("{} exists", display); } ...
Read MoreHow to standardize only numerical columns in an R data frame if categorical columns also exist?
The standardization of a numerical column can be easily done with the help of scale function but if we want to standardize multiple columns of a data frame if categorical columns also exist then mutate_if function of dplyr package will be used. For example, if we have a data frame df then it can be done as df%>%mutate_if(is.numeric, scale)Example1Consider the below data frame −> x1 x2 df1 df1Output x1 x2 1 c 4 2 c 1 3 a 4 4 a 1 5 b 0 6 c 4 7 c 2 8 ...
Read MoreHow to find the number of groupwise missing values in an R data frame?
In data science, we often face the problem of missing values and we need to define a way to replace them with an appropriate value or we can complete remove them. If we want to replace the missing then we also need to know how many missing values are there. Therefore, if we have a data frame with grouping column then finding the number of groupwise missing values can be done with aggregate function as shown in the below examples.Example1Consider the below data frame −> Group x df1 df1Output Group x 1 A 2 2 A ...
Read MoreHow to change the tick size using ggplot2 in R?
To change the tick size using ggplot2, we can use theme function with argument axis.ticks.length. For example, if we have a data frame called df that contains two columns say x and y then the scatterplot between x and y with larger size of tick marks can be created by using the below command −ggplot(df,aes(x,y))+geom_point()+theme(axis.ticks.length=unit(0.8,"inch"))ExampleConsider the below data frame −x
Read MoreUnsafe Operation in Rust Programming
Unsafe Operations are done when we want to ignore the norm that Rust provides us. There are different unsafe operations that we can use, mainly:dereferencing raw pointersaccessing or modifying static mutable variablescalling functions or methods which are unsafeThough it is not recommended by Rust that we should use unsafe operations at all, we should use them only when we want to bypass the protections that are put in by the compiler.Raw Pointers In Rust, the raw pointers * and the references &T perform almost the same thing, but references are always safe, as they are guaranteed by the compiler to point ...
Read MoreVectors in Rust Programming
Vectors in Rust are like re-sizable arrays. They are used to store objects that are of the same type and they are stored contiguously in memoryLike Slices, their size is not known at compile-time and can grow or shrink accordingly. It is denoted by Vec in RustThe data stored in the vector is allocated on the heap.ExampleIn the below example, a vector named d is created using the Vec::new(); function that Rust provides.fn main() { let mut d: Vec = Vec::new(); d.push(10); d.push(11); println!("{:?}", d); d.pop(); println!("{:?}", d); }We push the elements into a ...
Read MoreWhile and For Range in Rust Programming
We know that Rust provides a loop keyword to run an infinite loop. But the more traditional way to run loops in any programming language is with either making use of the while loop or the for range loop.While LoopThe while loop is used to execute a code of block until a certain condition evaluates to true. Once the condition becomes false, the loop breaks and anything after the loop is then evaluated. In Rust, it is pretty much the same.ExampleConsider the example shown below:fn main() { let mut z = 1; while z < 20 { ...
Read MoreHow to convert the row values in a matrix to row percentage in R?
To convert the row values in a matrix to row percentage, we can find the row sums and divide each row value by this sum. For example, if we have a matrix called M then we can convert the row values in M to row percentage by using the commandround((M/rowSums(M))*100,2)ExampleConsider the below matrix −M1
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