For Loop Skipping last value for certain range of values

Hi, I wrote the following code using a for loop:

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This is supposed to output values from 0 to 1.5 in column A at 0.1 intervals.

The issue I'm facing is that for values upto t=1.3, the last output value is 1.3, However if I put t=1.4 it still gives the last value as 1.3

if t=1.5, last output value is 1.4! for t=1.6 last output is 1.7 and so on...

This continues till t=4.7, after which for t=4.8 last value is also 4.8


Any suggestions on what's going on?

Repeatedly adding 0.1 is one of the classic ways (going all the way back to the '70s and '80s) of illustrating floating point errors (probably more than you want to know in these links: https://www.excelforum.com/groups/ma...nd-errors.html ). When VBA comes to the next statement, it adds step to the current value, tests if that is less than or equal to upper limit, and only executes the loop again if the result of the boolean test is true. If the upper limit is 1.4, and the 1.3+0.1 addition results in 1.40000000001, then the test is false and the loop terminates without executing the i=1.4 iteration.

Solutions involve figuring out how to deal with the floating point error or avoid it altogether.

To avoid the issue, I might modify the code to work with integers instead. For i=1 to 14 step 1: debug.print i/10: next i
One could add a small error value to t so that floating point error will not cause the loop to terminate early. For i=1 to t+0.05 step 0.1: debug.print i: next i
One could use a Do...Loop where you can use a Round function and your own boolean test to better control loop termination i=0:Do Until Round(i,1)>t: debug.print i: i=i+1: Loop

or any other strategy that strikes your fancy.