An automatic way: foo.plot <- function(x,y,…) { lnames <- names(formals(legend)) pnames <- c(names(formals(plot.default)), names(par())) dots <- list(…) do.call(‘plot’, c(list(x = x, y = x), dots[names(dots) %in% pnames])) do.call(‘legend’, c(“bottomleft”, “bar”, pch = 1, dots[names(dots) %in% lnames])) } pch must be filtered from the lnames to avoid duplication in the legend call in case the user … Read more
Assumed shape dummy arguments (those with (:)) require explicit interface to the procedure to be available at the call site. That means the calling code must know how exactly the subroutine header looks like. See also Module calling an external procedure with implicit interface That explicit interface can be provided in several ways 1. preferred … Read more
The best practice is to place your procedures (subroutines and functions) in a module and then “use” that module from your main program or other procedures. You don’t need to “use” the module from other procedures of the same module. This will make the interface of the procedure explicit so that the calling program or … Read more
You cannot make similar tricks with functions in Fortran directly. You also cannot return a closure in Fortran. Just write a wrapper. function wrap_f(x) result(res) … res = f(a,b,…) end function It can be an internal or module function and get a and b by the host association or it can use the module containing … Read more
Modules are always the right thing to use đŸ˜‰ If you have a very simple F90 program you can include functions and subroutines in the ‘contains’ block: program simple implicit none integer :: x, y x = … y = myfunc(x) contains function myfunc(x) result(y) implicit none integer, intent(in) :: x integer :: y … … Read more
A parameter is the variable which is part of the method’s signature (method declaration). An argument is an expression used when calling the method. Consider the following code: void Foo(int i, float f) { // Do things } void Bar() { int anInt = 1; Foo(anInt, 2.0); } Here i and f are the parameters, … Read more
A function returns a value and a procedure just executes commands. The name function comes from math. It is used to calculate a value based on input. A procedure is a set of commands which can be executed in order. In most programming languages, even functions can have a set of commands. Hence the difference … Read more
You must defend against SQL injection whenever you turn user input into code. That includes table and column names coming from system catalogs or from direct user input alike. This way you also prevent trivial exceptions with non-standard identifiers. There are basically three built-in methods: 1. format() 1st query, sanitized: CREATE OR REPLACE FUNCTION foo(_t … Read more
I am going to try to keep this dead simple. A “callback” is any function that is called by another function which takes the first function as a parameter. A lot of the time, a “callback” is a function that is called when something happens. That something can be called an “event” in programmer-speak. Imagine … Read more