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Retrocomputing

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    yes, A=4/2 and A=3/2 will always produce a float no matter what. even if the result is integral in the end. I banged my head on the wall when I wrote an Oric basic to C converter because in C 3/2 yields 1... Good luck finding the bugs in the converted games... Commented Mar 16, 2020 at 22:44
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    The Integer variables in MS BASIC, at least on the 6502 variant, have only two real application: 1.) in some (fairly rare) situations assigning a result to an integer variable might save you one call to INT(X) when you need to throw away a fractional part, and 2.) and much more importantly, while simple integer variables take as much RAM as floats, integer arrays can be a big space saver - they take only 2+2*n bytes for n elements, not 2+5*n as float arrays do. Of course this has to be balanced against the slower processing and the additonal "percent" characters in your code. Commented Mar 17, 2020 at 12:35
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    "Interesting here is that the use of constants does not result any relevant speed up" - luck basically, you're using a one-byte ASCII const, as opposed to a one-byte var name. The rest of the conversion is the same. I'm curious what happens if you change 3 to 3000 etc. Commented Mar 17, 2020 at 15:02
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    For giggles, I wrote a 3-line program that set up 10 vars = 10 and then FOR I=1 TO 10000. On a C64 emu, that's 18.4 seconds. Adding a line 5 with I=0 reduces it to 14.4 seconds! Clearly the Atari approach is better and goes to show just how bad the FP code is. Commented Mar 17, 2020 at 15:06
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    To validate your test program, I modified it very slightly to run on a BBC Master: dropbox.com/s/yn0zzavdyiv8uxq/… This demonstrates that on a BASIC which does have native support for integers, they do have a performance benefit over floats. Commented Jun 27, 2020 at 21:14