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A X
12,842 PointsNot understanding what exactly %s is a stand-in for.
So in Craig's Intro to Java Course he introduces a stand in for a string variable as %s....but doesn't elaborate much on this, even though it's used heavily in the following videos. I'm not sure what exactly the % is...and if the "s" is merely an arbitrary letter or if the compiler doesn't "know" what type the stand-in is without the 's' for string. In a later video he mentions something like:
console.printf("%s is a %s dude", noun, adj);
Are these stand-ins for variables always presented this way? Wouldn't it be less confusing (at least to me) to re-write it like this:
console.printf(Noun + " is a" + Adj + " dude.") ;
Why would/wouldn't you want to use the variable names themselves vs. the %s stand-in?
4 Answers
Joseph Frazer
5,404 Points%s is a replacement area for a string. Lets say I have this string:
String myName = "Erick";
And if we want to print that string out in a middle of a string:
console.printf("My name is %s and I love programming!", myName);
What we do is replace the %s for a string variable. Using this makes it easier to place variables in middle of sentences without having to keep using the comma. And you can use whatever way is comfortable to your needs. If you have any further questions I am here to help!
Joseph Frazer
5,404 PointsNot exactly. For integers we use %d.
Joseph Frazer
5,404 PointsHere is a good reference to formatting: http://alvinalexander.com/programming/printf-format-cheat-sheet
Joseph Frazer
5,404 PointsBy using the comma I mean by adding. You used the plus which is perfectly fine. My , is your +.
A X
12,842 PointsA X
12,842 PointsJoseph Frazer : So would we need to change the % to %i for ints? Or %f for floats? Basically, is the alphabetical letter included after the % symbol arbitrary or does it serve a specific purpose, such as delineating the type? Like why couldn't I write:
console.printf("My name is % and % is % and the answer to the universe is %.", adv, verb, participle, number);I'm also not sure what you mean by "without having to keep using the comma"....are you referring to breaking up the sentence to insert the name of the variable?