The erase() method returns a new (valid) iterator that points to the next element after the deleted one. You can use this iterator to continue with the loop: std::vector<std::string>::iterator iter; for (iter = m_vPaths.begin(); iter != m_vPaths.end(); ) { if (::DeleteFile(iter->c_str())) iter = m_vPaths.erase(iter); else ++iter; }
DataFrame.iterrows is a generator which yields both the index and row (as a Series): import pandas as pd df = pd.DataFrame({‘c1’: [10, 11, 12], ‘c2’: [100, 110, 120]}) df = df.reset_index() # make sure indexes pair with number of rows for index, row in df.iterrows(): print(row[‘c1’], row[‘c2’]) 10 100 11 110 12 120 Obligatory disclaimer … Read more
Use the built-in function enumerate(): for idx, x in enumerate(xs): print(idx, x) It is non-pythonic to manually index via for i in range(len(xs)): x = xs[i] or manually manage an additional state variable. Check out PEP 279 for more.
From top left to bottom right var theArray = [“ABCD”,”EFGH”,”IJKL”]; var length = { “x” : theArray[0].length, “y” : theArray.length }; length.max = Math.max(length.x, length.y); var temp, k, x, y; for (k = 0; k <= 2 * (length.max – 1); ++k) { for (temp = [], y = length.y – 1; (x = k … Read more
You can do it like this without loops SELECT p.date, COALESCE(a.value, 0) value, p.grp_no FROM ( SELECT grp_no, date FROM ( SELECT grp_no, MIN(date) min_date, MAX(date) max_date FROM tableA GROUP BY grp_no ) q CROSS JOIN tableb b WHERE b.date BETWEEN q.min_date AND q.max_date ) p LEFT JOIN TableA a ON p.grp_no = a.grp_no AND … Read more
Object.hasOwnProperty determines if the whole property is defined in the object itself or in the prototype chain. In other words: do the so-called check if you want properties (either with data or functions) coming from no other place than the object itself. For example: function A() { this.x = “I’m an own property”; } A.prototype.y … Read more
For break and continue, the additional label lets you specify which loop you would like to refer to. For example, you may want to break/continue the outer loop instead of the one that you nested in. Here is an example from the Go Documentation: RowLoop: for y, row := range rows { for x, data … Read more
The solution is relatively simple: x = Dict(“a”=>”A”, “b”=>”B”, “c”=>”C”) for (key, value) in x print(key); print(value) end # Output: cCbBaA Check out the Julia docs for Base.Dict to learn more about functions you can apply to a Dictionary in Julia!
Angular does not provide this functionality out of the box. I think that the simplest way to achieve the desired result is to only display data on every third index like so: <div class=”list-group”> <div *ngFor=”let p of products; let idx = index” > <div class=”row” *ngIf=”idx % 3 === 0″> <app-product [product]=”products[idx]”></app-product> <app-product [product]=”products[idx+1]”></app-product> … Read more
Apparently the looping construct in SQLite is the WITH RECURSIVE clause. That documentation link has sample count-to-ten code, a Mandelbrot set plotter, and a Sudoku puzzle solver, all in pure SQL. Here’s an SQLite query that computes the Fibonacci sequence to give you a feel for it: sqlite> WITH RECURSIVE …> fibo (curr, next) …> … Read more