What is the formatter to make sure that + or - signs are always shown in front of the float value in printf() in C?
I haven't done C in a while, so where can I find a good reference on the web, any suggestions are appreciated
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Put a + sign after the % but before the field width, the precision specifier, or the f. For example, use "%+10.2f" for a ten character wide field with two digits after the decimal.
From printf(3):
+
A sign (+ or -) should always be placed before a number produced by a signed conversion. By default a sign is used only for negative numbers. A + overrides a space if both are used.
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PleaseStand
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1+1: but maybe add an example for clarity, e.g. `printf("x = %+g\n", x);` ? – Paul R Oct 16 '10 at 20:42
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"%+f" is what you're looking for (though note that when you print it, you'll actually be printing a double, not a float -- a float is implicitly promoted to double when passed to a function that doesn't have a prototype or for a variadic argument).
Jerry Coffin
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