Bug? for loop

Daestrum

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• Aug 17, 2014

• #1

if I use

B4X:

for a = 1.0 to 100.0 step 1
   ......
next

all works as expected.
if I change the step value to 0.5 then the for loop no longer executes.

Could it be because a is not defined as float / double ?

 

klaus

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• Aug 17, 2014

• #2

How did you dim a ?

This code works as expected !

B4X:

Dim a As Double
For a = 1 To 10 Step 0.5
    Log(a)
Next

 

Daestrum

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• Aug 17, 2014

• #3

That was my point, the for-next doesn't require a pre registered variable, you can just make one up on the fly
for a = ...
for b = ...
a and b don't need to be defined

Maybe it should give a warning that the control variable is not the same class as the value in the 'step' part of the loop.

 

klaus

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• Aug 17, 2014

• #4

You always should define variable types !
By default a none dimed variable is a String.
But if I remember well, if you don't define the increment variable for a For / Next loop it is parsed to an Int.

 

Erel

B4X founder

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• Aug 18, 2014

• #5

The For case is special. If the variable was not declared then it will be an Int (you can see it here: http://www.b4x.com/android/forum/pages/results/?query=for&page=1&prefix=0)

 

LucaMs

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• Aug 18, 2014

• #6

Maybe in the next version Erel could implement:

For A As Flat = 1 to 100 Step 0.5

But we could spend one more line:

Dim A As Flat
For A = 1 to 100 step 0.5

without sweating as he would sweat for that change.